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(Advice needed) Convert Brompton 6 speed into a race bike?

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(Advice needed) Convert Brompton 6 speed into a race bike?

Old 07-14-22, 11:01 AM
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brommiephillip
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(Advice needed) Convert Brompton 6 speed into a race bike?

Hey guys
I have been riding Bromptons for 10 years but about 1 year into my 6 speed, that ive taken more serious. (Pics below)
** Wont let me post the links *
I got a better setup for myself on the stem area, so I can have a proper height, and I got it fitted for me (Cut handlebars to size/width and all the correct measurements for me). I got some clip in shoes and these MKS pedals/quick release which I love. One side regular for normal shoes, and one side SPD for clip in.
Ive started to do 30-50 mile rides like this and would like to start riding with the Rapha local crew here in NYC and other 'big wheel' group rides... but I need to sustain 15-20mphs they said with lots of elevation.
Been training for about 2 months now and im getting better and stronger but the hills are brutal. Flats doing very well with this setup.
Questions and Advice needed - Im considering getting the Kousac wheel set here
** Wont let me post the links *
Maybe new chain ring 60T and 11T Variocoq
** Wont let me post the links *
New pedals for Look style. Anything to get it faster and better for the distance rides.
Can anyone comment on the Kousac upgrades or any other stuff you can recommend for me, for big rides with the 'big wheel' ppl?
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Old 07-14-22, 02:23 PM
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I'd say the best method would be to buy a race bike.
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Old 07-15-22, 01:12 AM
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Excellent subject!!! There was a brompton race in London (and a penny farthing one on the same day)
if you google that it will give you some ideas.

you may need range and a 3x2 might be limiting. For the 1kg, you might want to convert your rear hub to get more range and gears; alfine might be an option, there is even a di2 option but I m not sure where the battery would go.
either way, you will need to gear your bike to get 28/29GI to 120GI if you want to keep up with a peloton. Once you set the rear range, you can then define what chainring you need.
you may need to change your crank set, if so a ultegra hollowtec or a sram force1 could work with Associated BB


You may need a better aero position too; british riders have fitted TT bullhorn handle bar and possibly offset adaptor if you don t have a S model to begin with.
with this you can fit light weight bar end TT brake levers

then look at the chapter 3 spec to lighten it.

you might be able to find front wheels with fewer stoke to save some weight.

and obviously, slicks like schwalbe one

[img]blob:https://www.bikeforums.net/f0d0fb67-4e5f-4095-b086-c2e24d334a3e[/img]
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Old 07-15-22, 03:35 AM
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There's been no mention of the energy sapping rear suspension block on the Brompton. Every time you put pressure on the cranks a tiny bit of your energy is wasted compressing the suspension block. The harder you push, the more energy is lost to the bumper. I would replace it with a solid nylon block. I can't find one after a quick search, but it should be a simple job to make one from a suitable diameter of nylon rod for someone with reasonable DIY skills by just drilling a hole through the centre of the rod. I should add that it's many years since I owned a Brompton and the design of the block may have changed now which may mean a more complex solution is required than I'm suggesting here.
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Old 07-15-22, 10:20 AM
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Originally Posted by Jonesandrew View Post
There's been no mention of the energy sapping rear suspension block on the Brompton. Every time you put pressure on the cranks a tiny bit of your energy is wasted compressing the suspension block. The harder you push, the more energy is lost to the bumper. I would replace it with a solid nylon block. I can't find one after a quick search, but it should be a simple job to make one from a suitable diameter of nylon rod for someone with reasonable DIY skills by just drilling a hole through the centre of the rod. I should add that it's many years since I owned a Brompton and the design of the block may have changed now which may mean a more complex solution is required than I'm suggesting here.
The first or main problem for the Brompton is its small wheels. With smaller wheels, the effects of bumps are magnified. Energy is lost by the suspension block, but it would be lost anyway, as your body would act as the shock absorber. The energy would be dissipated by moving your organs and jarring your bones. Rear suspension on a small wheel bike can be a net benefit.
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Old 07-16-22, 03:54 AM
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Originally Posted by 2_i View Post
I'd say the best method would be to buy a race bike.
To the OP:

I agree with this wholeheartedly, but wouldn't it be cool if you could stay with a group like that with a Brommie? Most problems in the world of bicycles can be solved by throwing money at them, and this is no different. You can buy any part or component for a Brompton made of titanium or carbon fiber, so much that nothing will be left that is an OEM Brompton part/component. What you will wind up with it a bike like the one in this thread - Titanium Brompton clones update - which will weigh in somewhere around 11 pounds. Of course, you'll wind up easily spending as much as you would spend to get a worthy road bike. My advice is to do your research and weigh your priorities. For me, the best part about owning a Brompton is the fact that I can do all of these upgrades one at a time and still ride as I go about it.
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Old 07-16-22, 05:17 AM
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Originally Posted by J.Higgins View Post
To the OP:

I agree with this wholeheartedly, but wouldn't it be cool if you could stay with a group like that with a Brommie? Most problems in the world of bicycles can be solved by throwing money at them, and this is no different. You can buy any part or component for a Brompton made of titanium or carbon fiber, so much that nothing will be left that is an OEM Brompton part/component. What you will wind up with it a bike like the one in this thread - Titanium Brompton clones update - which will weigh in somewhere around 11 pounds. Of course, you'll wind up easily spending as much as you would spend to get a worthy road bike. My advice is to do your research and weigh your priorities. For me, the best part about owning a Brompton is the fact that I can do all of these upgrades one at a time and still ride as I go about it.
Follow this advice, and you will only end up with a lighter Brompton. You still won't be as fast as you would on a road bike.
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Old 07-16-22, 09:35 AM
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Originally Posted by Schwinnsta View Post
Follow this advice, and you will only end up with a lighter Brompton. You still won't be as fast as you would on a road bike.
Well at least you'd have a better chance at staying with the pack for a while longer!
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Old 07-17-22, 06:58 PM
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Been there (sort of), done that and also see quite a bit of such.

I have used 18", 406, 451 bikes and I do ride them with my regular road riding friends.
I have also seen another guy attempt to do it and I will elaborate on his attempt.

Bike Friday Tikit souped up with large crank, aero wheels and aero bars.
Its basically as good as it gets for a fast 16" bike. (oh yeah, aero helm too )
Fit guy, regular enough rider, about 1.75m or taller, not over weight.
Every Tues night there would be this ride of about 40km and he'd turn up with his bike and he'd just get trashed.
I actually fared far better with a 451 bike.

My own conclusions is that better roll over, better compliance over small road irregularities and less frictional losses due to less rpm of parts make the 700c bike faster.
Add to that, higher gearing which the road rider will switch to on the descents to drop the small wheeler who has already run out of gears. .

Put it another way.
In the usual weekend rides on my road bike, I am on the head of the group, often doing the pulls and first 3 to reach some established 'end' markers.
On the small wheeled bike (451 Bike Friday Super Pro), I will either do no or shorter pulls and probably drop to being 3-6th.

So, my advice is to just get a road bike (2nd hand or even a decent priced alu one )
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Old 07-18-22, 07:32 PM
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Why not consider adding e-assist? Brompton has a system and there are front hub conversion kits. Swytch can be set to 15 or 20mph, you will still be working your but off but it will keep you with the pack on the climbs.

Or if you really like British folding bikes get a Chameleon and you will be all set on group riding.
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