The first 6-speed Bromptons reached dealers in the week ending 13th April 2002, and we obtained an example to test on 18th April - it should have been a day or two earlier, but it was delayed in transit. The report below will be added to on a regular basis as we get more experience of the new model.
New: The 6-speed upgrade kit for 3-speed Sachs geared Bromptons
We now have some additional comments on the upgrade kit from John Shackford. [01/10/2002]
Our test machine is one of the first T6 models. As a 'T' model it has the rear rack and dynamo lighting. Normally I recommend to people that the L models represent better value - the rear rack and lighting add nearly 1 Kg (2lb) to the weight, modern battery lights with LEDs are light, cheap, easily mounted, and offer good batter life, and on a Brompton the front carrier is far more useful than a rear one. The reason for specifying a T was that it is intended to use it for some rides later in the year where both front and rear carriers will be needed. For those who care about such things (I don't) the test bike is green. The only alteration to the standard specification was the fitting of the front luggage block, but immediately on its arrival, and before it was ridden, bar end extensions and a mirror were fitted, a different (Brooks Swift) saddle was substituted, and a mirror was also fitted. Other changes which may be made later will be described in the report below.
The Brompton should be pretty well known to most of you (if not look elsewhere on this web site for more information), so I won't list all the standard features. The 6-speed system retains the Sachs 3-speed hub and changer (on the right hand side of the bars), but adds a second sprocket at the rear (a 15-tooth, in addition to the normal 13), a small, neat deflector to push the chain across to engage the appropriate gear, cabling to this changer and a lever mounted on the left hand side of the handlebars. The lever is in the upper position in high gear, and the lower position for low gear, and ingeniously incorporates a small 'ping' bell. A narrower, 3/32in, chain is used. Our example exhibited a few other changes in specification from other Bromptons we have seen, but whether these are specific to the 6-speeds or are on all current models we are not sure - these detail changes are described in the first part of the report below.
Unpacking a Brompton from its box is a pretty simple operation - just lift the folded bike out, unfold it, and you are ready to ride. The front luggage mounting block was already fitted, but I had a few other accessories to fit before doing any riding - namely a more comfortable saddle (for the moment a Brooks Swift, well broken in on another bike), computer (Cateye Mity 3), short bar end extensions and a mirror. The version of the manual included with the bike describes the operation and adjustment of the new derailleur system - not just an add-on, but an integral part of the manual; a separate sheet specifies the 6-speed gearing, and quotes the additional weight of the 6-speed system over the 3-speed as 200gm. At 45 psi, the tyres were a bit on the soft side, so more air was put in, the front mudguard stay, which was rubbing on the front wheel, was bent to centre the mudguard, the chain, which had dropped of the chainwheel in transit, was put back in place, and I took a quick ride up to the pillar box with some post.
I have an old 1990 T5 (modified to L specification, and with various other changes over the years), and a very heavily modified newer model is SP form, but I've never used one of the Mark III Bromptons, nor the Sachs hub gear. I was obviously aware of some of the specification changes which have been made to the basic machine, but some minor details were unexpected - it's good to see a company making continuous improvement to their product, and not resting on their laurels, however successful they are. The details which were unexpected from my point of view include:
Riding the bike for the first time, I was conscious of how high the standard gearing is - at least by my standards. My T5 has gearing lower than the lowest Brompton option, and the SP version is similarly low geared. I should have specified the 12% gear reduction for the T6, but not only did I forget, but it would have delayed delivery - Brompton quote the 12% reduction as being a built-to order feature, not a dealer modification. A 44-tooth chainring was immediately placed on order! A few adjustments to the bar end extensions and saddle achieved a comfortable riding position (at least over a very short test ride!), although the positioning of the bar ends does result in the one resting on the ground when the bike is folded, and moving it to avoid such contact gives an unsuitable angle when riding. The current handlebars are also higher than on my old T5 - I would prefer something even lower than on the older bike.
But of course the key question is how the new gears perform. This was my first experience with a Sachs 3-speed hub, and I haven't used a recent Sturmey-Archer 3-speed either. My old 5-speed Sturmey-Archer (the two-cable version )can be quite difficult to change gear downwards, notably when stationary, though the newer 5-speed on the Micro did not cause much problem. The 3-speed Sachs changes gear very cleanly, though the different feel of the lever, and lever angle, will take a bit of getting used to; several times I thought I was in top on the hub, and was actually in middle gear, part of the confusion in my mind arising of course from the fact that the new bike was so much higher geared than my other machines. The lever movement perhaps feels less positive than the Sturmey-Archer one, but the actual gear change is rather more positive. More interesting, of course, is the process of changing rear sprocket using the left hand lever. This moves very easily and positively between the cogs, and though the operation is not completely silent, it is quite quiet and undramatic. It is a bit disconcerting, though, that one should be pedalling when changing sprocket, and not pedalling when changing the hub gear - it is likely to take quite a while I think before this comes naturally. The answer may simply to be to drastically reduce pedalling effort for all changes, which should accommodate both the hub and derailleur. I have always found that my Sturmey-Archer hub gears change better if you keep pedalling, but with much reduced effort when changing. Having the lever in the logical arrangement, ie up for high gear, down for low, and only two positions, makes it fairly easy to see what gear is engaged. The problem which arises, though, and one I was well aware of, is the change pattern. In numerical terms, the 6-speed gives good gear spacing and a reasonable range, namely (in inches):
1 : 40.3
2 : 46.5
3 : 54.8
4 : 63.3
5 : 74.6
6 : 86.1
However, to go through the gears from bottom to top involves the following lever settings:
After only 3 short rides, I certainly haven't got familiar with this - I know the pattern, but keeping track of just which gear is engaged and what to do next requires, at least at present, quite a lot of concentration. Whether this will become natural with more experience remains to be seen - I suspect not. Just using the hub gears alone - ie treating it as a 3-speed hub with an overdrive on top (or an underdrive on bottom, if you prefer) might suit some, but for me the gear spacing of the hub is much too wide for normal riding - though there are times (eg just after the top of a hill) when a quick change up on the hub is convenient without having to go through intermediate gears.
While doing the first test rides, I carried out a rolling resistance run on my usual test route. The air was fairly still, but without testing other, known performers, at the same time, I would not try to read too much into the results. However, the results were pretty good - not as good as the best I have tested, but to the upper end of the mid range performers. This was with the standard (non-Kevlar) Brompton tyres well inflated - it is my first experience of these tyres, which have received very favourable reports from others.
The other thing that struck me was the brakes -these felt much better than on my old T5, which has an Alhonga (obtained before the Brompton version was available) on the front and the original CLB (not the later Saccon) on the back. The rims and shoes are of course still very new and clean, and a realistic comparison will only be possible after some wear and accumulation of road grime, but if they remain as effective as they are at present, I will have no complaints at all.
Before I do any more riding, the bike will receive the usual attention of new machines - a check over all the bolts, some rust prevention treatment, and perhaps some treatment to try to prevent the usual problem of water ingress into the mudguards, which is very unsightly. Then of course I need to take some photographs to illustrate this report.
Look forward to more reports on the bike in the next few days: it should very soon be going on a longer trip, to Skye.
I've now read the T6 manual (I know you should do this first, but if you've owned an earlier model before, the temptation is to skip it). The method of handling gear changes (just reduce the load applied, which will suit both hub and derailleur) which I suggested is also what the manual advises. I must say, I think the manual is excellent - it isn't written for those who will never open it anyway, but strikes a good balance between providing basic information for everyone and details for those who will/can do their own maintenance. No dumbing down here - if you don't do maintenance yourself (no suggestion by myself or the manual that this makes you dumb or 'inferior' in any way), you can just skip some paragraphs. As I plan to fit a smaller chainring, I thought I would use this as an excuse to ring the factory to double check chain length. As usual, I got a prompt and very knowledgeable response, and I used the opportunity as an excuse to ask who wrote the manuals - as I suspected it is Andrew Ritchie himself. I hesitate to offer congratulations, as it seems presumptuous for me to do so.
I don't go in for naming inanimate objects; my Bike Friday New World Tourist is known as The NeWT as convenient abbreviation more than anything else. However, the fact that the T6 is green, and that my wish to ride it more today has been thwarted by rain, leads to it having gained the name "Henry"!
My old T5 has had the rear rack and dynamo removed to reduce its weight, so that it is in effect an L5. I've made a number of modifications to further reduce the weight, the most notable in this respect being a carbon fibre seatpost and Flite Titanium saddle, but other modifications aimed at improving performance have offset these weight savings. The net result is that the old T5 is not my lightest bike - though it is interesting how little difference there is in the weight of all my bikes in the form in which I ride them, despite the fact that manufacturers' paper specifications suggest bigger differences would be expected. The Folder and A to B have remarked in the past on the fact that older Bromptons, such as mine, are heavier than new ones (many folders start life apparently light, but have to be strengthened and gain weight during their production life - it is to Brompton's credit that the opposite applies to their machines). Anyway, I thought a weighing sessions was called for.
First let me qualify the results which appear below. I don't have any specialised weighing equipment - I just use the bathroom scales. In the case of the Brompton, this is fairly simple, as I can balance a Brompton on the scales and take a reading quite easily. With other bikes I have to weigh myself, and then stand on the scales holding the bike, which tends to make taking a reading awkward, and any wobbling in the process results in a fluctuating reading, not to mention the fact that some variation can occur depending on exactly how I balance and hold the bike. In the case of weighing the Bromptons, the comparative results should be quite accurate (to less than 1 pound), but the actual weight shown on the scales is not especially reliable, so don't use the figures quoted below for comparisons with any weights from other sources. Also, the weights are for the bikes as I measured them - with the modifications I have made and the extras fitted. In particular, the old T5 is measured with the CF seat post and Flite saddle (also fitted to the SP), while the new T6 is measured with a standard seat post, Brooks Swift saddle and a small Carradice saddlebag. These are the results:
Old (1990) Brompton T5 in L5 configuration (ie no
rear carrier and no dynamo and dynamo lights): 25.5 pounds
SP Brompton 7-speed: 25.5 pounds
New T6: 27.5 pounds
All the weights are quoted in pounds rather than kilograms, because that is what the scales read, and it is unwise to rely on the absolute values, so the figures are for direct comparison only.
The T5 had a small rear LCD battery lamp fitted, but no front lamp, and the SP has an SP rear rack but no lights. As mentioned above, the T6 has its rear rack, dynamo and lights, standard seat post and Brooks Swift saddle, and a Carradice saddlebag. I weighed the saddlebag before fitting, and it was almost exactly 1 pound (weighed on equally accurate/inaccurate kitchen scales!). The saddle and seatpost must account for getting on for another 1 pound in difference, so in more equal configuration, there would be almost no difference in weight - except that the T6 has the dynamo and rear rack, which I reckoned accounted for almost 2 pounds when I removed them from the old T5.
Taking account of the differences in specification, the figures certainly suggest the new 6-speed bike is lighter than the old 5-speed one. This may be due in part to the difference in weight between the old 5-speed hub and its dual controls and the new 3-speed hub and derailleur system, but I think it does also suggest that the latest bike is lighter than the 12 year old one. According to the specification, the new 6-speed increases the weight over a 3-speed by just 200 gm, so the weight penalty of opting for a 6- rather than 3-speed is quite small, and less than it was in going from a 3-speed to the Sturmey-Archer 5-speed (either the final version or the early one on my T5); I would strongly suspect that efficiency is higher as well with the current 6-speed - the old 5-speed certainly both sounded and felt very inefficient in its lowest gear. The new 6-speed also offers much more even spacing of the rears, albeit with a distinctly awkward pattern of using the two levers to go through the range. The overall gear range is also not quite as great as that on the old 5-speed.
You may be wondering why the SP is no lighter than the others. I think that this can be relatively easily explained in that mine has an SP rear carrier - I don't know the weight, but it seems likely that it is over 8 ounces and perhaps as much as a pound. Furthermore, although the SP is modified in some respects to reduce weight, some of the other modifications, which greatly improve its performance, increase the weight again - for example, V-brakes and the suspension stem.
In conclusion, I can only note again how similar the weight of all my bikes is in the form in which I ride them. The new T6 has small overall advantages over the comparable 5-speed Sturmey-Archer version, and the bike overall is lighter than a much earlier model with an older 5-speed. The weight penalty compared with a 3-speed is small. The bike may still feel quite heavy to carry, but in absolute terms it isn't really all that heavy, and the thing to remember about a Brompton is that it is so easy and quick to fold, and bagging is rarely needed, that folding can be left to the very last minute, and the bike can be moved around on its wheels until then, so the amount of carrying involved should be small.
Yesterday the T6 had its first serious outing, with a ride to Sandwell & Dudley station and a train journey to Swindon, before taking part in the first Swindon Smallwheels ride. As always, a Brompton is a pleasure to fold and very easy to transport by train, but the various changes of train did involve rather a lot of lugging it around stations, and no folder that I know of is light enough to make this a pleasure. The other good thing about a Brompton on a train is that one rarely feels the need to bag it, unlike some other makes, because the folded package is so compact and tidy. Bagging and un-bagging of most folders takes longer than the actual folding operation, especially if you include the time to unfold and fold the bag itself.
On the ride itself the bike performed faultlessly, though I did not that I haven't got the saddle position quite right yet. Compared with the 12 year old T5, the new T6 felt more free running and stiffer - less flex in the handlebar stem. The 3-speed Sachs hub seemed to make a louder ticking sound both in drive and coasting, but of course without the rattling that accompanies coasting with an old Sturmey-Archer hub.
Apart from the two minor things which needed correcting after its journey in a cardboard box from London (putting the chain back on and bending the mudguard stays slightly), I have noted a couple of very minor defects - really hardly worth mentioning, but for the sake of completeness I suppose they should be recorded. The fist is that the Brompton transfer on the main frame has unsightly bubbles in it. This is actually due to the fact that it is on a part of the frame which is not completely straight, so inevitably the not very flexible thick label cannot make contact properly over its whole surface. It's a very minor detail, but surprising that such a thorough company has not resolved it. The second point is that, due to the quite constrained cable run to the front brakes, making a very sharp turn - so sharp that it actually only occurs when manoeuvering the bike by hand - the front brakes come on - either there needs to be a bit more cable, slightly less constraint on the cable runs, or I need to back the brakes off just a shade. Incidentally, when carrying the bike folded, the folding pedal gets pushed against the frame, damaging the Brompton label and soon scratching the frame, something that affects all Bromptons - a pity they can't arrange a stop or some protection to avoid this.
Prior to the ride I had spent some time working out a simple way to deal with the changing pattern required to go through the gears, which, as described earlier in this report, looks very confusing on paper. The methodology I developed worked well on the road, so I'll describe it here - bear in mind that it is much easier to apply than to describe. First, the easy case. If you want to make a change of two gears, for example near the bottom of a hill, after reaching the top of a hill, or before re-starting after a stop, just use the hub gear change on the right of the bars. The hub will of course change gear when the bike is stationary. The more awkward case if going progressively up or down through the gears, so I'll now describe my easy way for keeping track of this process.
The trick is to look at the left hand (derailleur) lever:
Changing up: If you want to change up, and the left hand lever is in the lower position, move it to the upper position. If you want to change up, and the left hand lever is in the upper position, move the left hand lever down and the hub (right hand) lever up.
Changing down: If you want to change down and the left hand lever is in the upper position, just move it to the lower position. If you want to change down and the left hand lever is already in the down position, move it up and move the hub (right hand) lever down.
That's all there is to it, and it is much easier to do than it is to described, and it very quickly becomes second nature to follow this process.
Incidentally, note that, contrary to what you may have read elsewhere, you cannot change the derailleur gear when the bike is stationary. Just like any derailleur changer, you can move the changer lever through a single gear position when the bike (strictly speaking, the chainwheel) is not moving, but it is physically impossible for the gear to actually change until the chain is being moved around. The effect of moving the lever when stationary is to place a strain on the chain and mechanism, and to cause an awkward change just as the bike starts moving - not pleasant for either the rider or the mechanism. So on any derailleur, including the Brompton, please don't try to change the derailleur gear while the bike is stationary (or more accurately, while the chainwheel is not rotating).
Further thoughts on the gear ratios
This first serious ride confirmed that for me the standard gearing is too high, and I will need to fit a 44-tooth chainring. However, Phil Wray commented on the same ride that he found the gearing on his T6 was too low - but then he is younger and stronger than I am. The 44 tooth ring will move the range from the current 40.3 - 86.1 in. to 35.5 - 75.8 in.
In the report on the six speed in A to B Issue 29, an alternative of using 12 and 16 tooth sprockets (and 44-tooth ring) in place of the 13 and 15 is discussed. Looking at their figures, I don't personally find this appealing - it certainly results in an attractive wider overall range (33.3 - 82.1 in), but results in several virtual duplications of gear, so that what you have is in effect only a 4-speed with wide spacing between the gears. If you are comfortable with the wide spacing of a conventional 3-speed hub, and would like a wider range of gears, this may be a good solution (if it is possible to fit these sprockets), but for me the reduction of the painfully wide gap between the ratios of the 3-speed is much more important.
Henry has been to the dentist and had 6 teeth extracted - yes, a 44 tooth chainring has now been fitted. The process is in principle quite simple - remove the old right-hand crank set in the usual way, fit the new one, take a pair of links out of the chain, and that's it. If you are using a Brompton 44-tooth crankset, be warned that you need one intended for the 6-speed models. The 44 tooth ring on 3-speeds is for a 1/8in chain, and is therefore slightly thicker than on the 6-speeds, which use a 3/32in chain, so that the chain rides up on the top of the chainring, and is reluctant to let go at the bottom. Apparently if you buy a conversion kit for a 3-speed, a 1/8 chain and the existing ring are retained - see the notes on upgrading below. My thanks are due to Mike at Phoenix Cycles and Barbara at Brompton for very speedily getting the right crankset to me so that I could fit it in time for this report, and more importantly in time for my visit to Skye.
Once the correct 44-tooth ring had been fitted, everything performed perfectly on a 35Km test ride - gear changes take place as well as before, but the gearing is much more to my taste. If anything, I would still like slightly lower gearing at the bottom end of the range, although I would be reluctant to give up much more at the top end. The plan at the moment is to take the T6 to Skye (unless I change my mind at the last minute and use the SP Brompton instead), so this terrain, with a considerable load, should be a good test of the gearing - or the rider.
I had always planned to use the new T6 for my visit to a photographic workshop on Skye at the end of April/beginning of May. A Brompton was favourite for this trip as I had it in mind to take a larger camera bag (actually a backpack) which I could conveniently strap to the front carrier in place of the usual bag - I would not consider using a large back pack like this on my back on a bike. This backpack could not be fitted easily on my other folders, though a Moulton rear carrier would take it conveniently, but at the expense of bike portability and flexibility of travel arrangements. At the last minute I nearly changed my mind and used the SP (a bit lighter and more gears), but I finally kept to the original plan of using the T6, so that I could continue testing, even though in the end I reverted to a smaller camera outfit which fitted into the Brompton front bag (larger touring version). A tripod fitted conveniently on the rear rack, although having to remove it to fold was a bit inconvenient. The total load on the front, including the rack, was 29 pounds (measured rather inaccurately on my scales), and 3.5 pounds on the back.
I won't bore you with details of my nightmare train journey to Inverness, suffice it to say that with missed connections etc I was very glad of the flexibility which a folder gave - no requirement for a booking for the bike, and no need for it to share the luggage van with a group of inebriated rugby supporters. After an overnight stay in Inverness, I took a train to Kyle of Lochalsh (once again glad of the flexibility of a folder) and then cycled to my destination, a few kilometres beyond Broadford. With the additional load on board, I would have like some lower gears, especially with a moderately strong head wind, and in the blustery conditions I opted to push over the bridge to Skye. From there to Broadford was not too bad, though most of the time was spent in gears 3 and 4. The handling remained quite acceptable despite the load, though obviously not as good as without the load. The brakes felt more than adequate even with this additional weight (remember that I am just under 9 stone, so the total load on the bike was still not all that great).
During the week of the workshop we travelled around by minibus, so the T6 didn't get any use, but to avoid the possible problems of weekend travel by rail, I stayed on an extra couple of days afterwards, and the T6 did get some use those days, when I went out with a fair amount of photographic gear. I only did about 50Km each day, mainly because I was spending a lot of time on the photography. The T6 performed excellently both days, though again I did feel I would have liked an additional lower gear in reserve in these conditions and with a load.
The journey back was much less stressful than the outward journey, and travelling in this direction I was able to get over the bridge (using bottom gear at one stage) without any pushing.
Overall the T6 proved quite adequate for this sort of outing. I wouldn't really want to put any more load on it - apart from anything else, I would really be struggling to carry anything heavier when loading the bike onto a train! I had no problems at all with the bike, and the brakes certainly felt entirely adequate with the considerable weight of luggage and relatively low weight of myself. The gear change worked excellently, and I now really do not give the apparently awkward gear change pattern any thought at all. Even with the lower gear option, with this sort of load on board I would have appreciated a lower gear, but even so, I only pushed on 4 occasions - three times going up the drive out of the place I was staying (VERY steep, and possibly not rideable even with a lot more gears and no luggage) and one over the bridge on the way to Skye.
Clearly a Brompton can be used quite satisfactorily for this sort of outing, and I know people who undertake much more ambitious tours on them. I would have to say, though, that personally it would not be my ideal choice in future - the SP with a slight weight saving and an extra gear, and more low gears, would be better if staying with the Brompton format, or a Bike Friday, Airnimal or Birdy would be more to my taste. A Moulton might well be better still for riding, but would be much less convenient from the point of view of taking it on the train.
Since returning from Skye, I haven't been out all that much - a combination of poor weather and some very major work on the house has interfered with cycling. I've been using the T6 for routine commuting rides, sometimes extended on the way back if the weather permits. Really thee is nothing to report regarding its performance - as always with a Brompton, it is superb for this sort of travel, as it is so easy to get on a train, take the bike into the office for safe storage, carry documents, disks, computers and other paraphernalia in the front bag, etc. The closer spacing of the gears of the T6 is much more to my taste than that of the 3- and 5- speed hub gear systems.
I'm very pleased with the T6 - it retains all the many excellent features of other Bromptons, and the additional gears are a big advantage from my point of view. For my style of cycling, the low gear option is essential, and even then I could probably live with slightly lower gearing. The overall range of the gearing is increased a little over a 3-speed, though not all that much, which is why bottom gear remains rather high for me, but the much closer spacing between the gears eliminates the problem I used to have with 3-speeds of pedalling like a maniac, changing up, and then having the knees creaking under the load. Although the gear change pattern may seem awkward theoretically, or on first acquaintance, with the two levers, in practice one soon gets used to the pattern, especially if you apply the logic described earlier.
Congratulations to Brompton on an excellent addition to their range, and one which helps to maintain the fact that Brompton sets the standard by which all other compact folders are judged..
By John Shackford
At last the day arrived for me to collect my Brompton long awaited gear 'upgrade'. I think this should really be called additional gearing rather than upgrade however. This kit introduces a slightly lower (about 3" lower) and a slightly higher (about 6" higher) gear.
The kit looks very impressive when first viewed, and indeed when fitted it too looks rather good. The fitting instructions were very long and indeed only if you have a reasonable amount of technical knowledge would it be good for you to proceed any further! I feel, however, after fitting the upgrade that maybe, just maybe the instructions are a little too elaborate. Probably the reason is to cover all eventualities with the fitting by non bike technicians!
Andrew Ritchie certainly deserve praise for this little kit. It does what it says on the box and, indeed transforms the slow little 3 speed into something with a rather advantageous range of gears. It's not just useful for the commuter but indeed for those like myself who use the Brompton for long (35 + miles) trips out into the countryside on the weekend. I shall indeed be out on this Sunday enjoying my new range out ratios.
Having only had a short tour round the block today it was noticeable that the bike was uplifted, as it were, from a little shopping bike into something probably a tiny bit better than the old 5 speed Sprinter. Having owned a 5 speed previously I really was a little sorry to now only have the 3 gears. No doubt about it, the bike has arrived home back on the scene-at last!
Finally to say that the fitting, following the instructions to the letter, took about an hour to complete. If I were to fit another (highly unlikely) I think it would probably be fitted in about 45 mins. For the record the kit includes all the relevant parts including a new chain and the tiny but clever little bell fitted as part of the gear lever itself. No doubt if no bell had been included, then many complaints would have been forthcoming from those wondering where to fit a bell convenient to hand as it were!
All in all a satisfactory day.
After my initial short ride yesterday I decided that the shining sun was too good to miss. So after a hearty breakfast off I went for the usual 32 mile loop I ride. This takes a fairly leisurely route along mainly country lanes with the odd short but reasonably steep hill.
The start went extremely well and indeed I felt that top gear was in fact too low! My initial thoughts soon turned to dismay-in fact I had a brisk tailwind on the outward part of my ride and on the homeward, that wonderful cyclists' friend-a headwind.
So, the gears themselves. Worked well and after some adjustment to my normal gear changing routine I find that I have fallen into a new routine. The gears now are used with some variety. I think I shall probably use the top and bottom ratios the most. I have found that much similarity exists to the early Sturmey Archer S52 which too used two gear shifters. My feeling is that the usage will bear toward using the higher 13 tooth as a sort of overdrive and, when in low gear the 15 tooth will be used in a similar fashion. Maybe as an 'underdrive'?
All told I feel the £65:00 which I paid to support a reasonably local (98 miles away) bike shop was money spent well and I can heartily recommend the kit to others.
One small point. I have noticed that this new kit seems just a little more noisy than the bike with just the one cog. Something I feel to do with the newly fitted tensioner. This noise may I suppose gradually quieten with use. We shall see.
I have been useing the Brompton fitted with the 6 speed conversion kit in its basic shop sold form.
Readers will remember how I mentioned that whilst I was very pleased with the result of this modification, I was somewhat irritated by increased noise from the drivetrain.
I have read that the chain and chainwheel fitted to the shop sold 6 speed, is in fact the narrow version as used for standard type deraileur gearing, and indeed some mention has been made on this site.
I decided that after a few months of regular riding, that the noisy chain was an irritaition too much.. I therefore have now fitted a Stronglight 100 LX chainset and a narrow chain.
HEAVEN! No more noise and indeed extra smooth gear changes. I heartily recommend this to all wishing to uprate the Brompton.
John Shackford, September 30th 2002
By Chris Green
I too have now carried out the 6-speed conversion to my previously 3-speed Brompton, which I bought in March 2002. The conversion kit cost me £65 from Bike Trax and arrived shortly before I went on holiday. Despite straining at the leash to get on with it, I had to satisfy myself that the manifest of parts was complete and tootled off to Portugal for 2 weeks.
Heartened by the previous writer’s article, and having the requisite tools, drivers, allen keys etc I decided to have a bash myself on my return. Knowing that I had to have my bike (I’m a part-time Cycling Proficiency Instructor) by Friday, I started work on this on Monday evening, “just in case”. Now I’m not a complete mechanical novice but I do stop short of the Haynes Manual “Remove Engine” level of proficiency so I was duly sceptical of other's claims that it only takes an hour.
Following the comprehensive instructions to the letter was a doddle, tedious but a doddle, nonetheless. The constant use of very long abbreviations got a bit tiresome though, and I frequently had to look back several pages to remind myself what the hell I was to do next, and with what. The job did however take me a couple of hours, but only because the circlip holding the old cog in place didn’t want to come out without a fight. Once removed, the rest was easy, except putting the circlip back on. Next time I'll buy a circlip expander first.
Even final adjustment was easy to comprehend and carry out. My advice would be to set aside a whole afternoon to this project, find yourself a nice bench in good light, and work on the bike upside down. It worked for me. Then if you whiz through the actual fitting, you’ve got plenty of time to iron out any bugs and make any fine adjustments before dark!
On first use, the chain tensioning cogs seem a bit over noisy, especially when the smaller of the two derailleur cogs is selected. Hopefully, this will “ride up with wear” as they used to say on “Are You Being Served”. Shifting seems commendably slick, especially onto the larger cog.
On a general note, the kids I teach seem to polarise into two camps vis-à-vis the Brompton, they either think it’s silly or “cool”, a bit like the reaction my wife gets to her Smart car really.
Here’s a tip of my own invention to stop your folding pedal marring your nice new paintwork when folded. I’ve attached a plumber’s pipe clip (you know, those white PVC things they screw to the wall, which then hold a copper pipe) to the rear forks at just the spot where to pedal tries to sit when folded.
Footnote: Differences between the kit and a factory 6-speed
As noted in the section on the T6, the new 6-speed bikes use a 3/32in chain instead of the 1/8in one of the 3-speeds, and this requires a slimmer chainring. To avoid the cost of a new right-hand crank set, the conversion kit is supplied with a 1/8in chain. This is reported to run as well as the 3/32 after running in. However, if you have already fitted a non-Brompton crankset, designed for a 3/32in chain (eg to lower the gearing still further), then you could use a 3/32in chain to advantage.
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Last updated: 1 October 2002