Brompton Speed Change
03-23-21, 08:59 PM
#1
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Brompton Speed Change
I have a standard 2s Brompton from 2018 (I think?) but the gearing should be 54T x 12/16. It's been fine but I think I'd like to make it a little speedier. Generally what are the pro/cons of switching out the chainring vs replacing both cogs? I think the ratio between the two is about right but I just want a slightly faster gear than 12 and 16.
03-23-21, 10:01 PM
#2
Schwinnasaur
I have a standard 2s Brompton from 2018 (I think?) but the gearing should be 54T x 12/16. It's been fine but I think I'd like to make it a little speedier. Generally what are the pro/cons of switching out the chainring vs replacing both cogs? I think the ratio between the two is about right but I just want a slightly faster gear than 12 and 16.
03-24-21, 03:51 AM
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There are third party cogs with 11t for the Brompton.
There is also a 3 speed conversion with 11-14-17t https://www.bikegang.co.uk/bikegangh...-9S-p194768178
There is also a 3 speed conversion with 11-14-17t https://www.bikegang.co.uk/bikegangh...-9S-p194768178
03-24-21, 06:23 AM
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There are third party cogs with 11t for the Brompton.
There is also a 3 speed conversion with 11-14-17t https://www.bikegang.co.uk/bikegangh...-9S-p194768178
There is also a 3 speed conversion with 11-14-17t https://www.bikegang.co.uk/bikegangh...-9S-p194768178
03-24-21, 07:53 AM
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03-24-21, 10:02 AM
#6
caaddict
I have a standard 2s Brompton from 2018 (I think?) but the gearing should be 54T x 12/16. It's been fine but I think I'd like to make it a little speedier. Generally what are the pro/cons of switching out the chainring vs replacing both cogs? I think the ratio between the two is about right but I just want a slightly faster gear than 12 and 16.
Last edited by iFold; 03-24-21 at 10:16 AM. Reason: was should be fast
05-15-24, 01:11 PM
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More top end needed, I’m spinning out !
I have a 2sp Brompton Lightweight with a 60 chain ring and I believe a 12/16 rear set-up.
I use the bike for training (fits in the car to work and inside home 17-20 miles) I’m finding I could do with a higher gear, so would it be better to go 61-62 on the front or try an after market 11 on the rear ?? Tia.
FYI I’m a low cadence rider.
I use the bike for training (fits in the car to work and inside home 17-20 miles) I’m finding I could do with a higher gear, so would it be better to go 61-62 on the front or try an after market 11 on the rear ?? Tia.
FYI I’m a low cadence rider.
05-15-24, 03:43 PM
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Moving from 60 to 61 or even 62t won't change a lot, 1.66% or 3.33%.
But moving from 12 to 11 will increase the gear inch by 8.3% which is a bigger increase.
BTW, you can do both!
For the chainring, you must check that it is compatible the hook that attach the folded front frame to the rear triangle.
But moving from 12 to 11 will increase the gear inch by 8.3% which is a bigger increase.
BTW, you can do both!
For the chainring, you must check that it is compatible the hook that attach the folded front frame to the rear triangle.
