The Folding Society

A Dahon Jetstream P8 (2005) and a Rohloff 14-speed hub gear


It is intended that this report will be updated on a regular basis, reflecting the ongoing experience of using this bike and hub. Latest entries will be at the end.

Headset update - the problems with the headset referred to in the earlier parts of the report have finally been resolved, as reported in the update of 6 November 2005.

Background

I'll start with the gear story, but that will develop into the P8 story, so either bear with the first few paragraphs if your main interest is the bike, or look for the subheading!

Gears

The story starts in June 2005. Like many folder owners, but especially those with Bromptons (which is probably the overall majority of folder owners in the UK), I had been interested for some time in the development of the Sturmey-Archer 8-speed hub gear. Perhaps I should explain to those who aren't aware, the Brompton folder has unusually narrow rear forks, which limits the options regarding what types of gears can be fitted; Brompton have been unwilling to widen the forks, as this would potentially compromise the extreme compactness of the bike when folded, which is the biggest, but by no means the only, virtue of the Brompton. The Sturmey 8 (I'll use this abbreviation from here on) was announced  about 2 years ago, though it's origins go back to before the very sad winding up of the UK company, and its subsequent purchase and transfer to Taiwan. Although the original announcement was for a hub too wide for the Brompton, there has been a general expectation that a narrow version would eventually appear, and Brompton would adopt it, greatly increasing the gear range and versatility of their very attractive folders.

To their credit, Sturmey have been cautious about the launch, and cycle manufacturers have generally been equally cautious about adopting the new system until it is fully sorted and proven. While it shows much promise, significant changes were taking place as recently as January 2005, and most potential users are still regarding it as not a fully proven product.

The other 8-speed hub on the market comes from - need we say? - Shimano. 

I've been thinking for a while of trying the Sturmey 8 when it seemed to have evolved to a suitable state, probably on a Brompton. However, some pictures of a major failure of a recent (pre-2005 version) hub which appeared on the Velovision web site caused me to have some doubts, and to re-evaluate the options. In particular, I re-evaluated the range of gears provided by the Sturmey 8. Now, if you are an anorak, you will know about gear ratios expressed in inches; if you are lucky enough not to be an anorak, ignore the figures (or perhaps the rest of the paragraph), and just look at the comments. The main features of a gear system for a rider are probably the range (highest and lowest) gears, and also the spacing of these gears (big gaps tend to result in pedalling like a maniac, changing up and then struggling to keep going, while the knees creak in sympathy). A derailleur gear system gives some control over this if you only have one front chainring, but once a second or third chainring is introduced, you get a lot more gears numerically, but many of them are not really useful additions, and the gear change pattern (using front and rear changers) can get complicated. A pure hub gear means there is no need to worry about two sets of gear changes, but the overall range is sometimes limited, and the spacing of the gears sometimes results in big gaps. The Dual Drive, 3x7, or 3x8, originally created by Sachs, now known as SRAM, gives both some of the benefits and some of the drawbacks of both systems (a wide gear range, but lots of overlap, etc)! The Sturmey 8 gives you no option over the gear spacing, like all hubs, though changing the chainring or rear sprocket allows you to move them to being relatively low or relatively high. Now the design of the Sturmey 8 means there is a (relatively) big gap between the two lowest (1 and 2) gears, and also the highest two gears (7 and 8). Choice of gearing is a very personal thing, but I came to the conclusion that to get a sensible lowest gear (which is the priority for me), there would be a rather large gap to the next gear, but more importantly, the result would be that although the highest gear was acceptable, there would be a big gap down to the next gear, which would be too low for my purposes. However I adjusted the overall range, the same problem existed. The Shimano 8 provides a much more evenly spaced range, but although the overall range is not bad, I really did not feel that it was really what I was hoping for, and anyway the hub is too wide for a Brompton.

Enter the Rohloff hub and Steve Parry. If you don't know, Steve, has been modifying bikes for many years, and since his return from Australia to the UK, he has been selling them as a part-time business (not his main source of income). I have a Brompton he fitted with a 7-speed derailleur and V brakes, and a splendid piece of work it is - though I don't always agree with him on what constitutes a desirable folder(!). Over a year ago, he produced a Brompton with a 14-speed Rohloff hub gear and hydraulic disc brakes. Given the unusually narrow rear forks of the Brompton, this required major surgery to the rear forks. The Rohloff offers a gear range of a bit over 500% (as much as, or more than, most wide range derailleurs with triple chainsets), and all 14 gears are different, useable, and progress in a linear way using just one gear control. Steve has sold several of these modified Bromptons - Brompton sell him a frame and other parts, but the bikes are known as SPs, not Bromptons, I guess for product liability and warranty reasons; Steve's ideas may well have had some influence though on Brompton's decision early in 2005 to start offering some lightweight, and custom built models.

Having decided that the Sturmey 8 was probably not what I was looking for, I thought about getting one of Steve's Rohloff/disc braked bikes based on a Brompton. It would have many virtues, but I'm not all that keen on disc brakes, still less keen on hydraulic brakes, and the end result was a bit on the heavy side to my mind. When I talked to Steve on the telephone, he mentioned a project he was working on based on the very light, 16 inch wheeled  Dahon Presto Light. It was rather a jump in the thought process, but it triggered for me the idea of using one of the 20-inch wheeled Dahons with a Rohloff instead. This would be a much simpler, cheaper, and lighter conversion than a Brompton; there would be some sacrifice in portability (though a folded Dahon is reasonably compact, and the fold is exceptionally easy), but overall this was far more in line with MY needs (readers of this site will know that I always emphasis that choice depends on personal requirements, so don't assume that because this was best for me, I am suggesting it is best for anyone else).

I did briefly look at some other options. The Birdy Grey is Rohloff-based, but the price is excessive, and, justifiably or otherwise, I just have not got on with the two Birdys I have owned in the past. St John Street Cycles are very enthusiastic about the Rohloff hub, and have some VERY useful articles on the subject, but their offerings are not folders, with all the associated difficulties of a relatively conventional large wheeler.

The bike

So, I was looking for a 20-inch wheeled bike in which to fit a VERY EXPENSIVE hub gear system. Needless to say, the budget is important here - the hub gear was going to cost well over £600, which meant that it would be pretty silly to set a budget of £200 for the bike, but equally I did not want to spend thousands of pounds on the bike either. I thought of using one of my existing (embarrassingly numerous) folders as the basis for the Rohloff machine, but wither they were so good as they stand that I would not want to change them, or I was not convinced that they would really provide a satisfactory platform for testing the Rohloff. The most obvious candidate was my Dahon Jetstream XP, which is very light, and a joy to ride, but slightly lacking in overall gear range for my purposes (at least for the 100Km Brevet Populaires I sometimes ride, in possibly hilly country). I had the idea of getting a 2005 model and using the older 2004 machine for the conversion (the outstanding feature of these bikes is the light weight, so in a way compromising this with a heavier hub is sacrilege, but on the other hand helps to keep the final weight down). Unfortunately, or in terms of cost fortunately, the 2005 XP is not coming to the UK. When I bought the XP late in 2004, I was very tempted by the much cheaper P8 (and it has front suspension as well), but when I was offered an ex-demonstrator XP at an attractive price, I jumped at that. So when the 2005 XP was unavailable, my thoughts turned to the P8 again. 2004 P8s were available in the UK at very attractive prices, but the 2005 model looks MUCH better: lighter, what looks like better front suspension, more rigid frame etc. So that's what I decided to get to try the Rohloff. 

Please don't misunderstand: the P8 was chosen on merit - reasonably compact fold, very easy fold, full suspension, reasonable weight etc, but also a good potential recipient for the Rohloff hub.

The standard Dahon Jetstream P8

Although I bought the P8 with the intention of fitting a Rohloff hub, I always intended to try it in ints original form for 2 reasons:

1. To evaluate the standard model.

2. Cost of the Rohloff hub!!

In the end I only rode about 170Km on the bike in standard form, including 2 rides of over 70Km. Most of this was on-road, but a significant proportion was on reasonably well surfaced canal towpaths. The comments in this section relate to using the bike during that time (a couple of weeks).

The bike arrived very quickly after it was ordered via Cyclemotion. On unpacking it from the box, I was disconcerted to find that substantial force was required to turn the handlebars (far more than just stiff). Examination of the bike and the manuals (one very general on Dahons, and another on folders) indicated that a 10mm allen key way required to adjust the headset - fortunately I relatively recently bought an expensive set of allen keys which has one of this size, but for many people this would be a problem!. Loosening the headset to the point where the handlebars could be turned freely resulted in what I thought was too much slack in a rocking sense (apply the front brake, then push the bike forwards and backwards). I was a bit unhappy with this, and put the special 10mm allen key in my saddlebag in case of problems. More on this subject later ...

I usually spend a bit of time customising a bike to suit me, and then gradually refine it over a few weeks or months. Knowing I intended to change the gearing anyway, the first stage of customisation was not as extensive as it might otherwise have been. A Carradice SQ bag mount went on the back, to take either existing Trax or Barley bags - bear in mind if you plan to use this excellent system with one of these bikes, you need to order the large seatpost SQR system (Carradice will swap the standard one for the large diameter one if necessary). The saddle was moved back to about 2/3 of the rearward adjustment. Handlebar height is NOT adjustable on this model. The 2004 Jetstream XP had a huge range of handlebar height adjustment (though not low enough for me!), although at the expensive of a little loss of rigidity in the stem. The new stem is quite rigid, but the lack of any form of height and reach adjustment is unfortunate (!) -  there is a quick release to allow the handlebars to be rotated, which seems largely irrelevant, and adds to cost and weight. If there is no height adjustment (and the extra rigidity is a benefit), then why to fit a conventional handlebar stem at the top, which could be replaced with one of different reach and/or angle to accommodate the rider?

The other fittings at this stage consisted of a Cateye Cordless 7 cycle computer, a handlebar-mounted lamp bracket (also Cateye) and an R-K mini map mount. I was dismayed to find no provision for mounting a bottle cage - the 2004 XP had mounts in a VERY impractical position, but at least it had some. I used cable ties to attach a bracket for the Blackburn Airstick pump, but as yet the mounting of a water bottle has not been properly resolved (in fairness, Brompton and Birdy provide no mountings either, and the one on the Airnimal is almost useless, but on the other hand many Bike Fridays have no less than 3 sets of mountings). I fitted my preferred  (in the absence in the UK of demountable SPD pedals from MKS) Shimano 324 pedals, which have SPD fittings on one side, and are plain on the other.

After only a small number of rides, it is difficult to judge the bike in its original condition, but I'll offer the following comments.

Overall, in its original form, I thought the P8 was a good machine, though there were a few areas of concern, such as the headset and the transmission.

Fitting a Rohloff hub

Originally I expected to have to wait to fit the Rohloff 14-speed hub to the P8 for financial reasons. There was, unfortunately, no change in the financial situation, but I was persuaded to access my savings! Just a couple of weeks after I got the bike, there was one of the monthly Origami Rides, held early in July at Malvern. I went there with my Pashley/Brilliant Micro, while a friend was using my Jetstream XP. Unexpectedly, Steve Parry was at the meeting, with one of his Rohloff-hubbed SPs, and another Origami regular was also there with a New Series/Speed Moulton similarly equipped. I talked to Steve about the plans I had for the Rohloff in the P8, and he was very interested, and offered to fit it for me. Now, in undertaking any project like this, even if it is fairly straightforward, one is conscious of the problems of knowing exactly which bits to order, and dealing with any problems which might arise. Steve has fitted a lot of Rohloffs in the past (probably more in the UK than anyone other than St John Street Cycles), and has parts in stock. So I was persuaded to go ahead sooner than I had intended. I met up with another folder enthusiast, Chris Dent, on Tuesday 12th at Slimbridge, and he took the P8 down to Steve, and the Rohloff was fitted the next day.

Steve had advised me to go for the 15 tooth rear sprocket on the Rohloff, combined with the existing 52 tooth chain ring, rather than the 13 tooth sprocket and 48 tooth ring I had been considering. An advantage of this is that the 15 tooth sprocket can be turned around to give double the life, which cannot be done with the 13 tooth version. This lowered the gearing a shade from what I had been thinking of, but, as I'll explain later, this is actually a big advantage with the Rohloff, and something that St John Street Cycles discuss in their useful information on the Rohloff on their web site. The resultant gearing gives a range of 18 to 95 inches.

 Originally the plan had been that Steve would also fit a Brompton luggage block to the front, but Steve and Chris were very concerned about the headset (though I had not mentioned my problems to them) - they found, like me, that there seemed excessive rocking movement, and that trying to eliminate this resulted in the headset becoming too tight to rotate properly. Steve was of the opinion that there might be a component missing. I contacted Dahon and Cyclemotion on Thursday, and they sent me some headset parts, which arrived on Saturday, just in time to meet Chris at another folder ride, this time in Swindon! We and Mike Roberts, another experienced modifier of folder, examined the headset and the parts which had arrived that morning, but the parts were fairly generic, and included bits which obviously weren't appropriate. In the end we concluded that one flexible spacer, might be missing. We fitted this, but although it did improve matters, none of us were entirely happy with the result - it still seemed necessary to tighten the headset to the point at which the steering was not as free as it should be, but at the same time there was perceptible rocking if the front brake was applied and the bike pushed gently forwards and backwards. I can't say that the plastic friction bearings represented a particularly impressive form of headset bearing either - I'd really be much happier to see 'proper' rolling bearings used. Anyway, I decided to go ahead and use the bike. [Correction - rolling bearings are used, but are completely enclosed and 'fixed' into the head tube via a spring clip, so it's not immediately obvious what they are. 15/8/2005]

Rohloff Day 1 - Saturday 12th July 2005 - Swindon Smallwheels Ride
 It was quite a hot day for riding, and after the excitement of taking the headset apart, I was not sorry that we only did about 18 miles riding. This was generally pretty flat, about half on roads and about half on cycle tracks. Initial impressions were that the hub worked very nicely in the top 7 gears, but, as has been widely reported elsewhere, there is a substantial drop in efficiency, and increase in noise, when the lower 7 are engaged, and the change from 8 to 7 needs a little more care. All these reports also indicate that the Rohloff needs some running in - 1000 miles or more - after which is will be smoother and quieter. From this first ride it was clear that the gear change is generally very good (two cables run from the handlebar control to the hub, and the actual selection is done at the hub, not in the handlebar control, which is a big advantage in a folder, as the folding and unfolding is not going to upset the gear change system, as happens with some folders). Nevertheless, at least slight relaxing of pedalling effort improves the change, and is particularly necessary for the 8-7 change. While this may be different from how one uses derailleurs, I'd rate it as no more of a problem, and probably less of one, than coping with the, not always consistent, behaviour of a derailleur system.

As far as efficiency goes, the need to run the Rohloff in meant that I was not seeking to make any final judgement at this point, but clearly the system was performing well in the top 7 gears, but a loss of efficiency occurs when going down to the lower 8. Incidentally, it's a pity that the marking on the changer twist grip makes it very difficult to read which gear is selected - raised black numbers on a black background are not the most legible. With the gearing fitted, 7th on my bike is 39 inches and 8th is 44 inches.

On return home, I marked the 8th gear position more clearly, and also 11th (direct drive), for convenience. I also weighed the bike - with all the accessories I had fitted, including the fixed part of the SQR bag, but not the bag and removable section, and of course without mudguards, the weight was 24 pounds before the Rohloff was fitted, and 27 pounds with the Rohloff. In view of the fact that a fully usable 14 gears were now available instead of 8, and the gears ranged from about 17 inches to 90 inches, instead of 30 inches to 85 inches, I think that is pretty good, and not much more than a double or triple ring derailleur system (which of course there is no provision for fitting on this bike anyway), and comparable with a dual drive system .

Day 2 - Redditch 109Km Brevet Populaire
I booked myself on this ride some months earlier, intending to try to do five 100Km events during the year. Most readers will probably judge this as pretty easy, and I would not dispute this, but I really don't find that anything over 100Km is practical, and in addition, while a 100Km ride is not much in itself, I do find that doing it as an event, with a very specific route to follow, in (admittedly easy ) time limits is much more wearing than a purely leisure ride of the same distance. I had been thinking at one point that this would be my third successive ride on a Moulton, but looking at a map I was a bit concerned by the number of contour lines, despite the official description of the ride being that it was 'undemanding'. I then switched to planning to use the Airnimal Chameleon (to my mind my best bike for this sort of ride), but with the availability of the Jetstream P8 Rohloff ( or should I now call it a JS-SP 14?), I felt I must use it instead.

At the start of the 100Km event, I found (not surprisingly) that I was the only person using a small wheeler, a folder and a hub geared bike. At least the previous week there had been recumbents and a Tandem Twosday at Upton Magna! I deliberately waited to set off with the second group - I'm never a fast rider, and it is a big mistake to get dragged into riding faster than is comfortable, particularly at the start. I had no particular problems keeping up with the leaders of the second group (it's not a race, but it saves having to navigate if you can follow someone!), until the map holder worked loose, and not wanting the fixing screw to drop out, I stopped to fix it. I didn't see very many riders from that point onwards, except at the control stops/cafes - these were very busy, so a barely stopped, and just pressed on, being regularly overtaken by faster 'hares' later.

Despite the map, the publicity was correct, and this was an undemanding ride. I can only recall a couple of fairly steep climbs, and these were very short. This meant I was in the upper 7 gears nearly all the time - changing down to 7th produced an embarrassingly large increase in the transmission noise, and a painful increase in effort. Fortunately(?) the loss is so great when you drop to 7th that you almost immediately go down again to 6th, where the noise level and efficiency seem better. Curiously, after a few more down changes, the change back up to 8th from 7th does not give nearly as much sensation of a change in efficiency. Obviously the gears are still running in, and all reports suggest that this is a significant factor with a Rohloff, unlike most other gear systems, so I'm not passing judgement on the system yet.

The Dahon ran very well in itself, The suspension certainly felt hard, but it quite sufficient to take out the sting of bumps and other irregularities, and for a ride of this kind a degree of firmness is preferable to a very soft ride which wastes pedalling effort.

Up till about 12:30 conditions were quite pleasant - hot, but just enough movement of the air to avoid getting over-heated, while not offering any significant wind resistance. After that the air became very still, and the temperature increased, and the remainder of the ride was uncomfortably warm.

Overall, though, a very enjoyable ride, with an excellent route and no problems with the bike.

Preliminary comments on the P8 and the Rohloff

Although it's less refined than the Jetstream XP, and heavier, the P8 is quite a bit cheaper, and has the advantage of front suspension. Although I'm well pleased with it so far, I do think there are a few odd things about the specification, including the choice of a high bottom  bracket and full, quite stiff, suspension, but fitting of narrow, near slick Stelvio tyres and hydraulic brakes. If it were up to me, I'd lower the bottom bracket just a whisker, and then use the same frame with different fittings to suit at least 2 different types of customer - light off road user and light tourer (possibly commuter as well), with spring rates, tyres etc varied accordingly. Hydraulic brakes seem to me an unnecessary complication, cost, and weight. While this is not a heavy touring bike, it seems a pity that more luggage and mudguard options are not available at the time of writing. As you will have gathered, I'm not very happy with the headset either.

All other reports indicate the Rohloff needs running in. I'm very happy with it in the top 7 gears now, but I'm certainly hoping running in will improve the performance in the bottom 7 gears. Even allowing for such an improvement, I think that this reinforces the comments in the St John Street Cycles web site regarding how you choose to gear a bike with this hub. The range of over 500% gives a huge range of gears, but in choosing the chain ring size and sprocket, don't just look at getting the optimum top and bottom gears, but also look at where 8th gear will be. You really should be aiming that the change down to 7th does not occur until you have reached the point where you are working on a hill - you do not want to have to drop to this gear in more normal riding. The result is probably going to be that top, and indeed bottom, gears will be a bit lower than you might otherwise choose. The gear change works well, though a relaxation in pedalling at the time the change is made improves it, and really is necessary when changing from 7th to 8th. Although this is different from how one uses a derailleur, it's no more of a problem than dealing with the peculiarities of derailleurs. Listening to all the noise and drama associated with changing gear with a derailleur when riding in a group, the silence assocaited with a change on the Rohloff (except for the additional whirring when changing down to 7th) is most relaxing. Having such a large range operated with a single control, and no need to plan at which point to select another chainring, or the hub section of a dual drive, with an associated large jump in the gears, is a big advantage, as is the very even spacing of the gears. The fact that the mechanism is enclosed in a hub gear, unlike a derailleur, should also mean that it is better protected from damage, although from riding with others in the past I'm not entirely convinced about this, as probelms with hubs seem more common on such rides than with the derailleurs. 

More reports on the bike and hub will follow.

Minor update - 19th July 2005

I haven't ridden the bike since the 17th, other than a visit to the Post Office. However, the standard handlebars, which have an uplift, have been replaced with some flat ones, which should give a more appropriate height, and these were reduced in width compared with the originals by 9cm, which I think will also be more comfortable. Some mudguards have also been ordered - these are reported by other owners to suit the bike.

120Km ride and mudguards - 21 July 2005

The absence of mudguards is a limitation for anyone living in the UK, with our weather. A member of the Dahon forum reported that some mudguards sold by Bikefix, nominally for the Grasshopper recumbent, worked, so I ordered a set.  Apparently the Post Office tried to deliver yesterday (which would have been the day after the order was placed), but I was out, so I collected them at 07:00 this morning. Time limitations meant that I only fitted the front one - no problems apart from needing to shorten the stays. When I get round to putting up a photo, you will see that I have left EXCESSIVE clearance - this is partly because I may change the tyres later. The rear one would appear to be equally straightforward - shorten the stays and increase the angle between the stays. In both cases, some extra locating bolts are required as well. I'll leave fitting the rear mudguard until weather conditions show if it is necessary, or if I can get by with the Carradice SQR bag. I'd regard the front mudguard as much more necessary, as water thrown over the shoes makes for very unpleasant riding.

After fitting the front mudguard, there was still plenty of time to set out for a ride. I prefer to avoid the local main roads during the week, so a short trip down Wellington Road to pick up the official cycle route via Merry Hell to Stourbridge along the towpath is a good start; I don't go off the towpath on the route to Stourbridge though (the sign has been removed by vandals anyway), but stay on the canal towpath until I reach the Staffs and Worcs canal, which I follow to Swindon (no, NOT the one in Wiltshire!). I then take to some minor roads to Halfpenny Green Vineyards where I stop for coffee, light refreshments, and sometimes (including today) to buy a bottle of wine, even though it adds nearly 3 pounds to the weight I'm carrying! 

The options are then available to choose a relatively short ride, picking up the towpath again fairly soon after going through Trysull, or extending it to suit. Today I made a long loop of it - a nice day, a nice bike, and I was feeling fairly good. There was some wind, and after a rather dull strat it was brightening, so although cycling into the wind was not particularly enjoyable, it did avoid the heat being too oppressive. Up to the stop, the wind had seemed in my favour, but from here on until the halfway point, it was definitely against me. I rode via Bobbington on to Worfield. Here there is a hill which I'm very familiar with, and it was interesting to see how the JS SP14 would perform. I got up in 4th gear, which is about 26.3 inches - this seems to be in line with my (unpublished) impression that the weight of the system and the inefficiencies (at least while running in) meant that serious hills I would need to be about 1 gear lower than on pure derailleur system on a (consequently) lighter bike. Interestingly, compared with a 'Dual Drive' bike, which also suffers a weight penalty, the gearing in terms of inches is about the same. From Worfield I rode on past Stableford Bog, a rather unpleasant stretch of main road for 3 or 4 Km to Sutton Maddock, and then to Shifnal. I'd thought of turning back there, but everything felt good, so I though I would go on to the outskirts of Sherrifhales, and then turn back, after trying a few gentle climbs I'm fairly familiar with. 

Although the wind (such as it was), was still against me, things still felt good at Sherrifhales, so I went on just beyond there before deciding discretion was the better part of valour, and taking a right turn to begin the return journey. Turning back homward, the wind was definitely in my favour, and speed picked up immediately. This is familiar country (though I don't often make quite such a long loop of it), and I was particularly interested in how the P8, and more particularly the hub, handled the undulating terrain (no really big hills, some some gentle climbing). While in the upper 8 gears everything was fine, but changing down to the lower ones did obviously increase the effort - fortunately I didn't need to do that very often (8th is 44 inches). The gentle climb out of Seisdon was particularly interesting - I was reduced to just under 11kph, compared with about 12kph on some of my lighter bikes, but bear in mind that I had gone quite a bit further than usual today. I think that is quite good, and perhaps when the gears are run in, I would do better. The Dahon Zero G (26 inch wheels), with the original tyres, was down to about 9kph on this climb on a shorter ride - something I attributed at the time to the tyres, and a change of tyre confirmed, but it does serve to put things in perspective. Not long after, I picked up the Staffs and Worcs canal again, and followed this to the Birmingham/Wolverhampton junction, where I turned off to follow the towpath to Wolverhampton, then back to Tipton before joining the roads again for a short distance back home.

This is the second longest ride of the year for me, and one of the longest I've ever done (in the top ten, I'm ashamed to admit). I'd ridden a shorter version on the same bike before it was changed from an 8-speed derailleur to the Rohloff 14-speed hub. Broadly, my impressions of the basic bike are unchanged. The ride is good for me (I'm about 130 pounds, with the rear suspension pre-load at the minimum), and I could also bowl along very quickly on the good sections of the various towpaths - the suspension was definitely working, and was working well. However, on some parts of the towpath the suspension was definitely too hard for me; other, heavier, riders have also commented that the suspension seems hard. I think I'd prefer it a bit on the hard side, but I do wonder if Dahon might want to review it for 2006, and soften it a bit. What a pity there is no manual on the suspension, or this particular bike as a whole (it comes with a general Dahon bike leaflet and one on folders, both quite good in their own right, but nothing on the special features of the P8). If there were one, I'd hope to find information on adjusting the preload on the rear suspension - pretty obvious - but perhaps also something on changing the rear spring to a softer or harder one (not at all the same thing as preload), and perhaps on whether there is any adjustment available for the FRONT suspension too. Please don't get me wrong on this though - I'd like more adjusments, and probably slightly softer suspension, but nearly all other suspension systems, folder or non-folder, have similar, or some, limitations.

The general ride was very good - I stopped a couple of times to ease discomfort from the saddle, but this is much what I would expect, and overall I'm impressed by the SDG single rail system, though I'd love to be able to combine it with a Brooks B17 Titanium 'proper' saddle!

The new handlebars, non-risers and cut down by 4.5cm each end, suited me far better than the original set up, though obviously that is a personal matter. Although appearance is the last of my concerns, I think the bike looks better for the change as well.

The Magura brakes performed very nicely, but once when I had to brake unexpectedly, I did end up braking harder than I intended. Not only do hydraulic brakes add complexity and maintenance problems (which is why I do not like them), but for me they are too light. Of course, force required is a hugely personal factor - how strange that no company, not even Shimano, seems to have properly addressed this yet: it's obviously a major problem if you can't apply the force to the levers to get adequate retardation, but over-light brakes can be just as dangerous if they result in a wheel lock in a near (let alone real) emergency situation.

This ride was around 1/3 off-road, though only relatively gentle canal towpaths. The Stelvio is probably not the best choice of tyre in these conditions - rather narrow and high pressure. However, I had no problems with the version fitted to this bike on this ride (unlike the Stelvio Lights originally fitted to the 2004 XP, which I am less than happy with). This tyre is certainly good on road, and can live with at least light off-road riding, but I may well try something else later, which is one reason that the initial front mudguard fitting leaves an over-generous gap.

I commented earlier on the rather high bottom bracket - contrasting with my 2004 XP, which unquestionably has a rather low bottom bracket, which means care is needed cornering, or in rough terrain, to avoid a pedal hitting the ground. On this ride, I was happy with the bottom bracket height - it might be possible to reduce it just a fraction, but perhaps I over-reacted to the contrast after using the XP.

So, back to the transmission, the hub. It's still early days, and from other reports I'm expecting/hoping that it will get better. The wide range is amazing - you just keep on changing down, and never seem to run out of gears! So far I really haven't needed anything below 4th, though I have been lower either as an experiment or by mistake. Top is also more than adequate for nearly all my needs, though I suppose I could have used an extra gear a couple of times (though I certainly did not NEED it). Although I expect it to improve with running in, the questionmark is really associated with the change from the top 7 to the lower 7 gears. The location of this is not bad for me, but I may eventually decide to sacrifice a little at the top end to lower the 8-7 change point (a 48 tooth chainring in place of the standard 53?). As far as the quality of the gear change is concerned, it is always very positive (the real control is in the hub, not the handlebar control).  The behaviour varies a little depending on the gears being selected - I'd suggest a slight hesitation on any change is probably the best solution. In this respect it is actually much less temperamental than most derailleir systems that I have used, and much less likely to misbehave. It's a different process, but no worse, and in most respects better. Having such a wide range of gears available, with the ability to select the gear you want at any time takes some getting used to. For a straightforward hill, some planning of which gear to select and when is not so different, but there really is no need to make down changes before road junctions etc in such a careful way as with a derailleur - I still find myself changing down well in advance of possible problems even though I don't really need to!!

Overall, I still rate the P8 highly, though there are a few details (of specification, rather than underlying basic design) that seem odd to me. The hub is still running in, but I'm quite impressed so far. The fact that I did such a long ride, for me, so soon after having the bike and making a very major modification, speaks volumes for both the bike and hub.

Some points I should have mentioned earlier ...

The handling is very neutral - small wheels can make for sensitive handling, but on the P8 it is very stable - fairly 'quick', but not 'nervous'.

Fitting the flat, narrower bars means that I can't make use of the magnetic latch which holds the bars to the frame when folded. However, I'd found the magnetic latch ineffective, and there is nothing to keep the two parts of the frame together - I much preferred the 2004 XP system, in which the bars folded the opposite way, between the two frame sections, and a Velcro strap was provided to keep the two frame sections together when folded. I use a simple strap to hold everything together now on the P8.

There is nowhere to mount a bottle cage. My 2004 XP had mounts in a dreadful position, under the main frame, where a bottle would get dirty and was inaccessible. Still, anything is better than nothing, and the mounts also provided a means of mounting a pump. We seem to have lost even this on the 2005 P8. In fairness, most other folders are just as bad (full marks to Bike Friday who provide as many as THREE sets of mountings). [22/07/2005]

CycleFeast 2005

To avoid having to write several reports for different audiences, with a lot of overlap, I'm writing one combined report covering not only the Jetstream P8 with Rohloff hub, but the Cyclefeast 2005 event at which I used it. I've never been very good with names, and getting older does not improve things, so apologies if I can't always identify the people properly. if you are looking for more on the P8, please bear with teh first few paragraphs of this report, as they aren't related to this bike.

The very first CycleFeast event took place from 3rd to 8th August 2005, at Longridge Towers School near Berwick-upon-Tweed (far north east of England, for those who aren't familiar with it). Rather like Cyclefest (the very last of which was held at Lancaster in 2004), it is aimed particularly at enthusiastic cyclists who favour less conventional machines (Pedersens, Moultons, folders, recumbent bikes, recumbent tricycles) etc. An excellent report on the event in general by Sue Archer has already appeared on the Velovision web site, so I'm not going to say any more about the general issues, other than the fact that it was a huge success (57 attendees I believe, and an enormous variety of cycles, most being unconventional, but a good collection of more conventional diamond-frame road bikes as well).

I took the Jetstream P8 to the event, and also a Moulton fx8, so I'm going to use the opportunity to update my report on the P8 and its Rohloff hub (not standard on this bike of course), the fx8, and the other folders that were at the event. Both fitted into the Smart (with no passenger) without any problems, the front part of the fx8 occupying the passenger seat, along with some of my general luggage. 

I chose the Jetstream P8 for the event because it is new, I wanted to do some more testing of it and the Rohloff modification, and just because I like it! The Moulton fx8 went, to be perfectly honest, largely because I have temporarily at least, resumed the job of  Membership Secretary of the Moulton Bicycle Club, and wanted some pictures for possible use at the MBC Weekend in September - but its a good bike, and in many (though by no means all) a possible competitor for the P8. 

First, a few comments on the folders at the event.

Iris from Hawaii was the only other Dahon rider there - I'm not exactly sure of the model she had - Dahon's huge model range, and changes every year make it almost impossible to keep track of this, and confuse many potential owners.  It was an unsuspended model with an 8-speed derailleur, and a 2005 model. She seemed very happy with it, though had made a number of modifications prior to her trip to the UK. I'll comment at length on my P8 later.

There was just one Birdy - a Red, although several other participants own, or have owned, Birdys. I suppose I'm considered prejudiced, but I think that Birdy owners fall into two categories, those who have one and are very happy with them, and those who have tried them (sometimes more than once), but find them flawed. They are certainly continuously improved, which I commend, but for some of us, some of the original design features (tyres, luggage etc), and the compromise between portability and rideability don't really work. For light off-road use I think they are superb, and, if you can conquer the fear of the rather awkward folding system, and are strong enough to do it in the optimum way, they are very portable. Price, at least here in the UK, is rather against them too - the Red is just about acceptable here, but the otehr models are quite expensive, and you could probably buy a Red and convert it to a Rohloff-hub for less than they charge for a Grey (which comes as standard with a Rohloff hub), which has to be stupid!

Bike Friday had just 2 representatives - a very smart white Air model (suspension boom) with a Rohoff hub, and Michelle Whitworth on her faithful Pocket Rocket. Michelle's Rocket was as reliable as you expect of these bikes - I find them great fun (with the 451 wheels, but a bit disappointing in 406 form), but painful to ride on UK roads: I think that the New World Tourist model should have hyphens inserted - New-World Tourist, NOT New World Tourist - fine for touring the USA, but not many other parts of the world; to be fair, the reports of owners on their web site suggest that Americans do indeed venture very happily outside the USA on Bike Fridays. Most models are also quite expensive in th UK. Michelle always hates my saddles - perhaps this is partly because I generally ride bikes with suspension, so can use a firm saddle, but her Rocket has no suspension, and she relies on the saddle to compensate in part for the harsh ride.

Moultons don't fold, but most do separate, so I'll include them here. The Willisons (?) had a pair of very nice New Series stainless models, in maroon and French blue, Gertrud Ludwig had her very smart fx80, Chris Eley had his well-used ATB, just upgraded to a Rohloff hub and rear disc brake, I had the modified fx8, and there was also what I think was originally an old F-frame, but was so modified that I think Dr M would have words to say to the owner! Apart from the last of these, and myself, the owners hadn't brought anything else, and were well please with their bikes, which performed faultlessly throughout. As you would expect of a Moulton, they were not spectacular, but refined, comfortable, and very effective. Gertrud did the long, hilly ride on Saturday, which was beyond me - in terms of speed of the other riders I knew were taking part, if not distance. I'll refer to my own fx8 in more detail later.

Surpising ommisions from the event were Airnimals (at least two owners present though) - had it not been for my present Moulton commitment, I'd have taken my Chameleon as well as the P8, rather than the Moulton fx8.

Now a few very brief comments on the event ...

We were very lucky with the weather - I understand some of the evening rides to a local pub were a bit wet, but duiring the day, the conditions were dry, if a bit windy.

The rides were excellent in terms of destination - from a purely personal point of view, the longer rides were definitely a bit too fast for me, and the others were perhaps a bit short. The fact that a rider of Paul Stobbs's class (a VERY strong long distance rider) was leading the 'short' rides is indicative - he loaded his rather basic, heavy bike with everything in sight (I'm told this included a wooden folding stool) to make it more challenging for him! That said, Paul adapts his pace and style to suit those on the ride, so I think that anyone on his rides would not have a problem. The other rides did tend to be run at what is, for me, a rather fast pace - the distance was not a problem, but I can't ride fast (rider, not cycle), especially on hills. Some of the ride leaders left me for dead on hills - and they were on heavy, high recumbent tricycles (yes, Philip). Thank you to the other 3 riders on Sunday for slowing down and waiting for me on the long ride, but on some of the other rides, it was 'devil take the hindermost', and any assumption that they would wait at road juncion to show which was the correct route were seriously optimistic! I don't want to criticise, but I don't think I'm alone (based on talking to others) in wishing that some of the existing longer rides had also catered for the less young riders who prefer a moderate pace, without of course also providing for those who can go faster.

OK, now back to the main theme of this page - the Jetstream P8, modified with a Rohloff hub, and some comments on potential competitors.

I arrived at Longridge with about half an hour to spare before the first ride, which did not start until 11:00 to give those who, like me,  travelled from further afield time to take part (I had left home at 05:00). After moving some items into my room, I unloaded the P8, and was dismayed to find the front tyre flat - I hadn't used the bike for a few days, and had checked the pressures the previous eveing, adding just a little air. The puncture was on the inside of the tube, just by a spoke hole - the rim tape was commendably flexible, but rather narrow, and a little displaced from the centre, so I think the puncture was caused by rubbing on the hole where the recessed spoke is mounted - strange that it occurred in the car, but less embarrassing. I repaired the tube, though fitting a new one, by which time I was dismayed to find that the ride had left - fortunately, but not surprisingly, Paul Stobbs was still there checking for late starters, otherwise the event would have started even less auspicously for me. The ride on the first day was pretty short and gentle, though a few characteristics of the event were already becoming clear - the terrain was fairly hilly (long, moderate climbs for the most part, rather than shorter, steeper ascents and descents which I am used to), it was rather windy, not all that hot unless you were in the sun, rides were run at a fairly high speed, by my standards, and some of the recumbent tricycle riders were alarmingly strong and fast, leaving me for dead even on the ascents. 

On the second and third days, we rode to Etal and Ford, and then to Holy Island, and the P8 was again my chosen bike. On both these rides I wasn't able to keep up with the groups I started with on the way back, and it was a case of 'devil take the hindermost' - the assumption that someone would wait at a road junction where you did not go straight on proved to be mistaken, and I consequently I got lost, and rode further than I had intended. Mercifully I had bought the necessary Landranger maps the day before the event, and so managed to find my way back. On all three days, the P8 and Rohloff proved very satisfactory, though the ride of the P8 still feels quite hard to me for a full suspension folder. The range of gears on the Rohloff is amazing, and I only briefly used third gear once, otherwise finding fourth quite adequate for the steepest hills, and barely any need for any higher top gear. I once rounded a bend and encountered a steep ascent, which caused me to change down very quickly by several gears without relaxing pedal pressue, with the result that it engaged 14th unexpectedly. As there was no time to try to relax pedal pressure, I stopped, but was immediately able to select a still lower gear and then start off again. This was a bit embarrassing, but if you have to stop in too higher gear with a derailleur, you can't easily change down while while stationery, and although I had the occassional slight hiccup when changing into other gears without reducing pressue enough (habit from using derailleurs), I'd rate the change as certainly no worse than the best derailleur, if a bit different, and the range and simplicity (no multiple rings and multiple changers) better. The one further comment I'd make, though, is that if you get it right, the ability to use the front changer to go up (or down) 2 gears at once on a derailleur can be an advantage in some situations - but only if you choose the right point to make this change.

On the last two days I chose to use the Moulton fx8 - really just because I had taken it there, rather than any problem with the P8 and Rohloff. After getting lost when riding with/behind a group the previous two days, I did my own thing on the fourth day, although riding to one of the designated destinations. Riding at my own pace was really more comfortable, even if a bit unsociable. That day I would really have liked to have done the long ride, but it was definitely going to be hilly, and I realised that although I could cope with the distance and hills, the speed of the leaders and other riders would be too much for me. Riding the fx8, with double chainring and 9-speed cassette, was interesting compared with the P8, especially as part of the route was the same as I had ridden on the second day, especially the climb at Ford. Comparisons on this climb with the P8 and Rohloff are quite subjective, but although the Rohloff was in the lower gear range, and was whirring away busily, in practice I think the climb was no harder or slower than with the fx8, and the gear selected was no more than one lower (in terms of inches) on the Rohloff than with the fx8. On that basis, although the fx8 handled the climb well, I'd say that the Rohloff did rather better than I expected of it, given the weight and efficiency issues. As far as the bikes themselves go, the frame of the fx8 felt stiffer than the P8, especially in terms of the front end - I don't notice any flexing with the P8 when riding, but the Moulton definitely felt stronger in this area. The Moulton also had much more forgiving suspension - not soft for a rider of my weight (9 stone), but the P8 is really very hard. Both bikes were on Stelvio tyres, with a very similar overall bike weight, and the same luggage (Carradice SQR system). 

I had missed out on the long ride on day 4, and I should have been doing a 100Km Brevet that day if I had been in the Midlands, so, bravely, I decided to do the long ride on the final day - the same destination, St Abbs, as the shortest ride, but longer (however, the leader commented that it was probably not as hilly!). Only four of us did this ride - an Anthratec recumbent, Trice Micro, conventional diamond frame and myself. I'm afraid I did slow the others down - my thanks to them for moderating their pace - though I was not slow enough (I hope) for me to insist that they carry on without me. The recumbent trikes were frighteningly fast up hills - much faster than me, which shows that they were strong riders, as even I can just about hold my own with a lot of recumbet riders going up hills. On the other hand, I think that the fx8, with a light rider and narrow Stelvios, performed quite creditably on some difficult downhills, though of course not as fast as the trikes. The ride was certainly far from flat, but the range of gears of the fx8 was more than adequate. After riding the P8 earlier in the week, the fx8 suspension again felt much more compliant, and the Brooks B17 titanium saddle was superbly comfortable - the special SDG post/mounting/saddle of the P8 (and XP) is very satisfactory, but the Moulton suspension and Brooks saddle are still more comfortable. At the end of the ride, I had recorded 98Km, so, as I still was not worn out, I did a short ride down the main road and back to bring up the 100Km!

So why no photos? Well, the high speed of most rides meant there was no chance except at stops to take pictures. I did take a lot, but the slideshow I have produced takes over 40M of space, and the video of the visit to Holy Island, when combined with the slideshow, requires about 1.5G. So there is no question of putting it on the web in these forms. Ken Davison is compiling a CD of pictures taken by everyone at the event, which will be available to participants. If you want to see my pictures, let me know, and I'll see what I can do for you individually in terms of a CD or/and DVD. As a substitute, I offer the following simplified collections of pitures from the event:
Day 1 - Arrival and a fairly gentle ride to Berwick-upon-Tweed
Day 2 - A ride to Etal and Ford
Day 3 - A ride to Holy Island
Day 4 - Another visit for Fenton, for a display of birds of prey
Day 5 - A long, fast ride to St Abbs

Even these smaller photo reports have taken me to the limit of my web space, so they may have to be removed  quite soon.

This was a brilliant event, and many thanks to all who took part, and of course especially the organisers. 

Both bikes performed excellently. The suspension is good on both, but the P8 is really too hard - a view endorsed by everyone who has tried it (some are about double my weight, so it is not just an issue of the fact that I am quite light). It does mean you could get out of the saddle (honk) if you wanted with little if any suspension bounce, but I don't understand the logic of fitting suspension and then making it so hard, and apparently not offering any alternative rear spring (adjustment/changing the front unit does not look as practical). I'm not yet completely convinced by the Rohloff hub, at least given the high price, but there is no doubt that it performs very well, and has some advantages over a derailleur. Chris Eley has used one on an SP-Brompton for a considerable time, and is convinced, to the extent he had just converted his Moulton ATB. Interestingly, though his conversion is more recent than my P8 conversion, the serial number of his hub is several thousand earlier than mine, but it is exceptionally quiet and smooth - he considers mine much better than his earlier SP one, but not as good as his latest. I think this indicates that tolerances come into play here - an element of luck, but his latest is quite exceptionally sweet, while mine is probably more typical of the latest ones, and that the latest ones are improved over the earlier examples.

More thoughts on the Jetstream P8, and some possible competitors

I bought the Jestream P8 with the particular intention of converting it to take the Rohloff hub, rather than use it as supplied, though I did use it for some distance in ints original form. Choice of any bike, but especially a folder, is always a case of horses for courses. Possible competitors in terms of price and performance for the P8 include the Birdy Red (most direct competitor?), Moulton fx8 and Airnimal Joey. The Joey has no suspension, and is not a particularly compact folder, but the larger (24 inch) wheels probably compensate to some extent for the lack of suspension, and probably roll rather better under most conditions. For faster, longer road rides, and touring, with suitable carriers, I rate it's older brother, the Chameleon, very highly. I suppose some Bike Fridays should also be considered, but on UK roads I find the smaller wheels (406 or 451 20 inch, with no suspension) are painfully unforgiving, and the Air models don't really provide proper suspension; all the Bike Fridays are quite expensive in the UK.

The Birdys are also expensive here. The suspension is pretty effective, and for towpaths and bridelways I think they are very good. I'm less happy with the tyres - presumably the special edition with 406 wheels will eventually become standard though. Luggage carrying was originally a weakness - it's still less than ideal in my view, but this is a particularly weak area on the P8 too, which has lots of threaded bosses, but no proper official luggage system yet (mudguards are also a problem area on the P8 at present, despite mounting points).  In terms of a Rohloff hub, Birdy offer the Grey - but you could buy a Red and fit your own Rohloff for a lower price, which is complete nonsense. Some Birdy owners love their bikes, but a lot of people have had one and moved on to something else. Some (including myself) have gone back to a second Birdy, but have again parted with it for something else. The Birdy when folded is quite compact, though only a touch more compact than the P8, but the fold is not as easy as the Dahon one, and very few owners will fold a Birdy unless they really have to.

The comparison with a Pashley Moulton fx8 is particularly interesting - apples and oranges. The Moulton does not fold, though a separable version is an option. I would never buy the non-separating version! If you are looking for a true folder for regular commuting, the Moultons aren't going to be a contender. However, if the folding factor is associated with putting it in a car, then there is no real disadvantage. The P8 has, in theory quite sophisticated suspension, but the excessive stiffness cancels this out. The suspension quality in normal riding is better on the Moulton for this reason - the rear suspension of the P8 can be adjusted for preload, but even at the lightest setting, there is little movement even when  a heavy rider gets on board. The rear spring is marked as 140 N/mm, but there is no sign of alternative springs being available. Front suspension gives no indication of any means of adjustment. With the Moulton, there is not much you can do at the back, but the front is adjustable for preload. If anything it might be slightly soft for some people, but works very well for most. The Moulton concept is also radically different in a number of other respects. The fx8 has two mudguard options, and some really excellent front and rear carriers, purpose designed as part of the whole Moulton system, and not an after thought, as in the case of the Birdy. It also may only come with a simple 8-speed derailleur, but it has all the braze-on fittings to convert to multiple chainrings or the 3 x 8 dual drive system (no Rohloff-specific options yet though!). Dahon's relatively new P8 loses out in almost all these areas, and the significant model changes each year (not just in components, but frame design) make it less likely that we will see such features in the immediate future. The P8 design (2005) does not provide much in the way of handlebar height options either - I've replaced the riser bars with flat ones to lower the bars (i'm very short), but there is no other way of adjusting it. The Moulton has a standard stem fitting, which means you can replace the stem with one of different reach, angle or height (or an adjustable one). 

The P8 has an excellent spec, is reasonably priced, and has lots of potential. It makes a good platform for creating a Rohloff-hubbed folder. It's rather let down by the excessively stiff suspension, limited luggage (and mudguard) options, and at least on mine, by a dreadful headset (more on this in a moment). I'd have to say that the original 8-speed transmission (chain/cassette, changer) was very uninspiring too - you seemed to be able to feel every link in the chain as you pedalled, and the spacing of the cassette and the changer did not seem to be quite right, so that however you adjusted it, some changes would be clean, while others were slightly out of position. If you need real folding, for regular commuting, it is an excellent choice, subject to the above comments. If folding is less critical (ie, carry in a car sometimes, storage at home, but not taking it on a train regularly), then do take a look at the Moulton fx8 - less striking to look at, and much lower profile marketing, but a very versatile machine.

So, back to the headset on my P8. As mentioned earlier, when the bike arrived, it required substantial force to move the bars at all, and it certainly could not have been ridden like this. Slackening the headset to allow the bars to turn resulted in looseness in terms of fore and aft rocking. I settled for a compromise - some rocking, and too stiff. When Steve Parry converted it to a Rohloff, he expressed serious concern over the headset, as did Chris Dent who also looked at it. Both made these comments unprompted by me, and both are far more experienced modifiers of bikes than 95% or more of bike shops. I raised the issue with Dahon, and they very quickly sent me complete sets of parts to check/replace as required. Chris, Mike Roberts and I looked at these, fitted one additional item, and were still very unhappy with the result. In the 750Km of using the bike, it seems to be even worse now than originally - it is impossible to get free rotation without a substantial amount of fore and aft rocking. The polished internal steerer tube is now quite marked near the bottom - not sure why, but it might offer clues. I really have to rate the headset system as unacceptable in its current form, and so I've now taken the bike off the road completely. If I can acquire some proper headset bearings to fit, I'll do this and continue to enjoy the bike, but otherwise I'm afraid the Rohloff will have to move to something else. So what will happen to the P8 in that sad case? I don't feel I can sell it with the current headset arrangement, unless someone who understands the problem, and has the knowledge to take it on and solve the problem, makes an offer. Contact me if you are interested!

These crticisms of the P8 apart, which might just be unique to my bike, Dahon have some excellent machines. My 2004 Jetstream XP and Zero G have a few weaknesses, but they are really excellent bikes, and both have headsets and gear systems which are beyond criticism, though luggage and mudguards are also an issue with the Jetstream XP.

If I can resolve my problems with the headset, I'll be adding to this report on the P8 in the future.

Update: Headset problems resolved - a great bike [06/11/2005]

I hate having a bike which is not quite running right, so in order to sort the headset problems out I decided to try to buy a new headset which might contain a suitable crown race which I could use in place of the one that was missing on the bike. Of course you can't easily buy just a crown race, nor is it easy to determine whether what you buy is going to be suitable until you try it. In the end I bought three complete headsets before I managed to find something at all suitable - quite an expensive exercise. The final choice was a headset which contained a crown race which fitted quite well, but which lifted the frame a couple of millimeteres more above the fork assembly, which resulted in the amount of steerer tube onto which the handlebar assembly clamped being reduced by a rather worrying amount - the clamp bolt was now actually above the top of the tube onto which it clamped (though of course the main retention bolt, which screws down into the top of the fork assembly, was still very securely fixed). With the new crown race, the steering became silky smooth, with very little fore and aft rocking, proving that the absence of a crown race was the source of my problems. The bike was used in this form for a couple of months, although I was still slightly unhappy about the arrangement. During this time I kept in touch with the Dahon agents in the UK, Cyclemotion, and around the middle of October they managed to track down what they thought was the right item, which they sent to me. This certainly looked more like what was needed, although when I tried to fit it, the inner diameter was rather small, and would have required a lot of force in order to get it on - and then it would also have been nigh on impossible to get it off if it was not right. So I modified it slightly along the lines of the third-party one I had fitted, by sawing a split in it. It could then be pushed down quite easily, and when fitted it proved entirely satisfactory in terms of smooth steering, very little fore and aft rocking, and no adverse effects on the amount of steerer tube available on which to clamp the handlebar assembly (though I still think that a few more millimetres here would be desirable).

Despite the earlier headset problems, the Jetsream P8 is comfortably ahead of any of my other bikes in terms of distance covered this year, and I have only owned it since the middle of the year.  It's going to get even more use now the headset has been sorted.  I still need to identify a suitable replacement rear spring - the rating marked on the standard spring is just about the stiffest specification listed for  replacements, but the main problem is identifying a suitable length/diameter/etc replacement, rather than choosing the stiffness. The only other significant area in which there is some room for improvement (in my view) is in terms of carrying luggage - the Carradice Trax SQR system is fine for most of my purposes, but is not especially light, and is really not suitable as more than a day bag.  A larger saddlebag fitted via the SQR system would suffice for a long weekend, but for more than that (or for doing the shopping) one has a problem. I hate back packs, and would never use one for long rides, but I do have to resort to one when doing the shopping. I do also wish that there were some bottle mounting bosses - both for the bottle and to mount a pump.


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Last updated: 6 November 2005