Brompton 2 to Single Speed Conversion / Gearing
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Brompton 2 to Single Speed Conversion / Gearing
Hi all,
I currently have a 2 speed brompton and after having the cable snag a few times causing me to be stuck in the larger cog (which i never use) i decided just to remove the whole derailleur assembly (keeping the tensioner in place) so it permanently sits in the smallest cog which I'm very happy with but would like to make it look a bit more 'factory planned'.
I've already had the gears off the bike and back on for cleaning but know nothing of bike terms and how to gain measurements, can any one advise what spacer id need to buy in order to remove the larger of the 2 cogs entirely? id also like it to take into account that i didn't want to use (although I'm guessing many will advise against it) the plastic guard that sits nearest the wheel on the freehub.
lastly is it possible to easily fit an even smaller rear cog still (than the 12) or a larger chain ring (than the 54) without too much fuss and cost?
thanks
Dan
I currently have a 2 speed brompton and after having the cable snag a few times causing me to be stuck in the larger cog (which i never use) i decided just to remove the whole derailleur assembly (keeping the tensioner in place) so it permanently sits in the smallest cog which I'm very happy with but would like to make it look a bit more 'factory planned'.
I've already had the gears off the bike and back on for cleaning but know nothing of bike terms and how to gain measurements, can any one advise what spacer id need to buy in order to remove the larger of the 2 cogs entirely? id also like it to take into account that i didn't want to use (although I'm guessing many will advise against it) the plastic guard that sits nearest the wheel on the freehub.
lastly is it possible to easily fit an even smaller rear cog still (than the 12) or a larger chain ring (than the 54) without too much fuss and cost?
thanks
Dan
Last edited by danieledwards; 01-11-12 at 03:01 AM.
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From what I have read the wheels are the same. Here are some choices
https://www.brilliantbikes.co.uk/48-brompton-chainsets
https://www.brilliantbikes.co.uk/56-b...ts-and-spacers
https://www.brilliantbikes.co.uk/48-brompton-chainsets
https://www.brilliantbikes.co.uk/56-b...ts-and-spacers
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Speed Uno
Dawes Kingpin 2speed
Speed Uno
Dawes Kingpin 2speed
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thanks, i just had a reply back from brompton also confirming that it would be the QRSPRSTACK-BB1 - cheap as it is i didn't really want to buy the sprocket and was hoping to also remove the guard but at least there is a way - thanks!!!
https://www.brilliantbikes.co.uk/brom...bb1-stack.html
dan
https://www.brilliantbikes.co.uk/brom...bb1-stack.html
dan
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Not sure if you could fit a larger main. As with all mods on a Brompton maintaining the fold is problematic.
Again not sure if you could run with a smaller rear sprocket, if you could even find one.
A 54T * 12T single speed gives you a 74" gear which I find about right for Cambridge which is flat and for me spins out at about 23mph.
Regards
Jerry
Again not sure if you could run with a smaller rear sprocket, if you could even find one.
A 54T * 12T single speed gives you a 74" gear which I find about right for Cambridge which is flat and for me spins out at about 23mph.
Regards
Jerry
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Not sure if you could fit a larger main. As with all mods on a Brompton maintaining the fold is problematic.
Again not sure if you could run with a smaller rear sprocket, if you could even find one.
A 54T * 12T single speed gives you a 74" gear which I find about right for Cambridge which is flat and for me spins out at about 23mph.
Regards
Jerry
Again not sure if you could run with a smaller rear sprocket, if you could even find one.
A 54T * 12T single speed gives you a 74" gear which I find about right for Cambridge which is flat and for me spins out at about 23mph.
Regards
Jerry
still plenty enough to overtake everyone else on the commute (....aswell as the vehicles )
dan
#6
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Putting the 3 speed chain tensioner on will let you exchange the pulleys
to some different ones with sealed bearings .. rather than ,
the unique setup of the 2 speed 2 cog chain tensioner. which is self bushing ,
and has a skosh more friction.
to some different ones with sealed bearings .. rather than ,
the unique setup of the 2 speed 2 cog chain tensioner. which is self bushing ,
and has a skosh more friction.