Zipping up a Brompton M3L

ugo.santalucia

Predictably, my wife no longer uses her Brompton, as her new commute can be done by train.
I am thinking of using it in the cold season, maybe Bus in the morning and Brompton on the way home, to avoid morning ice.

I find it very sluggish and I wonder if there's anything I can do to make it a bit zippier. I could fit SPD pedals, maybe a non padded saddle, which seem the obvious thing to do... anything else that doesn't cost money?

I seem to recall removing mudguards will affect folding or something... can't remember what the problem was there

sloppyschleckonds

Sounds like you need to start doing some Vo2 max intervals again Ugo

asprilla

Aero is everything.

fenix

Schwalbe Kojak slick tyres pumped up correctly ?

It's not mudguards slowing you down....

I find the standard Brompton saddle fine - but maybe yours is an older one.

Clipless pedals will help too - but check out the Brompton World Champ videos - these bikes can shift.

ugo.santalucia

fenix wrote:

Schwalbe Kojak slick tyres pumped up correctly ?

It's not mudguards slowing you down....

I find the standard Brompton saddle fine - but maybe yours is an older one.

Clipless pedals will help too - but check out the Brompton World Champ videos - these bikes can shift.

Yes, on the flat it's fine (The worlds are on a flat course), but the undulations seem to kill the momentum. Do Kojaks really make a massive difference? I have the standard Brompton tyres, which are quite puncture resistant and I would avoid a puncture if possible

fenix

I've only had one puncture on the Kojaks when i hit something nasty. Otherwise they're pretty good. Got to be better than the standard tyres but I've not compared the two.

paul64

I know what you mean about sluggish Ugo compared with all of my other bikes. I have the same bike and same tyres and have found high pressure makes a big difference, the tyres say 100psi and I do go for 95-100 with the track pump and check them regularly.

After one ride I checked the bike weight at circa 12kg (with lights and a couple of other bits) and the Brompton bag with laptop and a a few bits another 8kg! No wonder with it's limited gearing it felt slow compared with even my winter bikes and their traditional-type groupsets (hardtail 15kg, gravel bike 12kg).

I still love the Brommie though!

ugo.santalucia

I might need the longer seat tube... that might be the issue going uphill... 5'10" on a good day... seems to be the limit for the normal one

vpnikolov

https://www.b-spokes.co/products/joseph ... d-brompton

:roll:

fenix

Something like this would save you a chunk of weight - https://www.sjscycles.co.uk/seat-posts/ ... n/?geoc=US

But a lot more weight from the wallet.

asprilla

fenix wrote:

Something like this would save you a chunk of weight - https://www.sjscycles.co.uk/seat-posts/ ... n/?geoc=US

But a lot more weight from the wallet.

I got mine on eBay. Exactly the same, but was about £50 and didn't have a brand etched into the side.

ugo.santalucia

I guess the only upgrade I would be prepared to pay for is tyres if they were really life changing... not bothered about the 3 Watts... but if it turned out to be 20, then I'd want them

elbowloh

I don't think Zipp do Brompton wheels...

ugo.santalucia

I think I need a longer seat pin.

Even with the clamp done as high up as it's safe to do and flipped to provide a more rear-ward sitting position, I am still about an inch lower than I would be normally. Typically I keep a top of the saddle to pedal spindle distance of 93 cm, and here I barely make 91.

20 quid for a longer pin might well solve all my woes

cougie

There's the long version and also the extendable version that Dave Miller uses. Might be worth looking at that.

ugo.santalucia

A lot more money though

meanredspider

I looked at the extended seat post but, with it, the “bike” wouldn’t have fitted between Dutch train seats. Added to which, my CofG would have been even further back.

ugo.santalucia

meanredspider wrote:

I looked at the extended seat post but, with it, the “bike” wouldn’t have fitted between Dutch train seats. Added to which, my CofG would have been even further back.

Luckily, I don't need to take trains... I might need to take it on a bus on icy mornings, but I don't think it will make a great deal of difference there... it's also a rather non-busy bus route.

Alternatives would be to use a "taller" saddle, although there aren't many taller than a Brooks and normally they are only taller because of padding that gets squashed once I sit.

It's a £ 20 upgrade, which might make a significant difference to whether I use the Brompton or not... so really keen to give it a go.

Worst case scenario, I have a £ 20 steel bar in my rucksack to persuade motorists to behave...

tgotb

I did a shedload of Brompton pimping a while back, and extending the seatpost was probably the single most effective change (followed by changing the bars, which moved the C of G, but that was a far bigger exercise).

I did it by cutting off the tapered top of the tube, cutting a short vertical slot, and then fitting a "normal" seatpost clamp and seatpost, as if it was a frame tube; that also allowed me to fit a normal saddle with rails. That said, it probably cost me more than £20.

ugo.santalucia

tgotb wrote:

I did a shedload of Brompton pimping a while back, and extending the seatpost was probably the single most effective change (followed by changing the bars, which moved the C of G, but that was a far bigger exercise).

I did it by cutting off the tapered top of the tube, cutting a short vertical slot, and then fitting a "normal" seatpost clamp and seatpost, as if it was a frame tube; that also allowed me to fit a normal saddle with rails. That said, it probably cost me more than £20.

I'd love the S type bars... it was my initial gripe, but my wife was adamant on the M... there is no way back, as a new stem would cost me an absolute fortune.

I also have the feeling with a better sitting position I could put down so much more power...

mtb-idle

Can you do anything with the rear rubber suspension bung* in terms of stiffening it up? Whenever I follow a Brompton rider the flex that thing allows is ridiculous and is of course lost energy that is not being put down on the road.

*I appreciate this may not be your exact model but you know the thing I mean.

ugo.santalucia

I did think about it, but it doesn't seem a massive loss... anyway, for 8 quid it's worth trying...

tgotb

ugo.santalucia wrote:

I'd love the S type bars... it was my initial gripe, but my wife was adamant on the M... there is no way back, as a new stem would cost me an absolute fortune.

I also have the feeling with a better sitting position I could put down so much more power...

My starting point was an M-type (shorter stem, I think) - I put a set of bullhorn bars on that, and it gives me a very similar position to my road bike (a bit lower than hoods, but not as low as drops). However that also needed a different shifter and different brake levers, so rather a big exercise.

I stiffened up the bung by strapping a jubilee clip around it. Don't know how much difference it made, but was very cheap!

asprilla

I also did the jubilee clip trick, but I sheathed the bung in exhaust hose first to avoid the clip damaging it.

If anyone needs the right sized hose I have 1m of it, less the length of a Brompton suspension bung.

ugo.santalucia

I ordered a bung from Brompton... 8 quid delivered

ugo.santalucia

Extended seat tube makes all the difference.. finally I can pedal properly!

ugo.santalucia

Yes, now it feels good!

https://www.strava.com/activities/1933729819

cougie

You're not hanging around on it are you ?

ugo.santalucia

cougie wrote:

You're not hanging around on it are you ?

Rode it like I stole it...

bendertherobot

Check out my ride on Strava: https://www.strava.com/activities/16059 ... m=referral

cougie

Also very speedy ! Most of my rides are in work kit so that'll be why mine are so slow. Yes. That's why.....