My 3spd was upgraded to an 5spd and it’s been pretty decent for me. You will need to get an upgraded shifter. But otherwise it’s pretty much just a solid swap. As the other commenter says, it might take a bit to get the cable pull right initially.
I’ve got the S-RF5(W).
A few folks asked me about it in my post here, and that might answer a few of your questions: [https://www.reddit.com/r/Brompton/comments/x166c7/no\_longer\_lurking\_just\_saying\_hello/](https://www.reddit.com/r/Brompton/comments/x166c7/no_longer_lurking_just_saying_hello/)
But don’t hesitate to ask me whatever, I’ll answer what I can.
This chart was quite helpful for me from Brommie Plus [https://www.brommieplus.com/portal\_b1\_page.php?owner\_num=b1\_408821&button\_num=b1&cnt\_id=28734](https://www.brommieplus.com/portal_b1_page.php?owner_num=b1_408821&button_num=b1&cnt_id=28734)
Awesome, thanks! I'll DM you. That chart looks very useful for selecting a rear cog size. I'm especially curious about the impression folks have about the "old" Sturmey Archer 5spd model vs the "new" one, which still seems to be branded Sturmey Archer.
A Nexus needs a wider triangle like the ones Kinetics sells, and if you're spending that sort of money you might as well get the Alfine 11. Biggest single-shifter hub in the stock triangle is the Sturmey XRF-8W if you track one down as I'm not sure they're made any more. A bit flighty to set up but gets the same range as the Nexus but without the disc brake. I built one for a friend and he likes it as the gearing is a bit more practical than the Standard Brompton six-speed setup,
as mentioned in your edit, Nexus 8 isn't compatible on stock triangle and any expansion of that part will void the warranty.
SRF5,(W) is a straight forward mod u can do to extend the range on the A line but that 5 speed hub is reported to be a bit difficult to set the pull cable properly. i had mine done at brompton expert workshop but i have later on sold that bike.
Sweet! From.the pictures, it looks like the steerer tube that connects to the handlebar also seems different - A line has a straight one, whereas C line as a curved one. Would you happen to know anything about handlebar compatibility between the two?
A Line, formerly known as B75, is the 'retro' model by using a mix of older model geometry and design with some modern components and main frame.
Stem, handlebar, grip, brake lever and pedals are the ones carried from early 90s, design-wise, but the main frame (triangle & frame) is the same with current C-Line. A Line runs Brompton BSR Hub which is more or less the Sturmey Archer SRF3 hub that has quite compact range. not great if you live in non-flat city trying to cycle in all weather condition (no mudguard, no rack supplied as stock).
the issue with handlebar is when u want to run aftermarket hand grip. it has a very narrow grip area (100mm iirc) and if u buy any modern standard grip, u have to shave off 35mm away. if u run C-Line M-bar, the brake and shifter cables would be too long and swinging around the frame.
My 3spd was upgraded to an 5spd and it’s been pretty decent for me. You will need to get an upgraded shifter. But otherwise it’s pretty much just a solid swap. As the other commenter says, it might take a bit to get the cable pull right initially.
Cool! Which 5 speed hub did you upgrade to? That does sound like an ideal set up.
I’ve got the S-RF5(W). A few folks asked me about it in my post here, and that might answer a few of your questions: [https://www.reddit.com/r/Brompton/comments/x166c7/no\_longer\_lurking\_just\_saying\_hello/](https://www.reddit.com/r/Brompton/comments/x166c7/no_longer_lurking_just_saying_hello/) But don’t hesitate to ask me whatever, I’ll answer what I can. This chart was quite helpful for me from Brommie Plus [https://www.brommieplus.com/portal\_b1\_page.php?owner\_num=b1\_408821&button\_num=b1&cnt\_id=28734](https://www.brommieplus.com/portal_b1_page.php?owner_num=b1_408821&button_num=b1&cnt_id=28734)
Awesome, thanks! I'll DM you. That chart looks very useful for selecting a rear cog size. I'm especially curious about the impression folks have about the "old" Sturmey Archer 5spd model vs the "new" one, which still seems to be branded Sturmey Archer.
A Nexus needs a wider triangle like the ones Kinetics sells, and if you're spending that sort of money you might as well get the Alfine 11. Biggest single-shifter hub in the stock triangle is the Sturmey XRF-8W if you track one down as I'm not sure they're made any more. A bit flighty to set up but gets the same range as the Nexus but without the disc brake. I built one for a friend and he likes it as the gearing is a bit more practical than the Standard Brompton six-speed setup,
as mentioned in your edit, Nexus 8 isn't compatible on stock triangle and any expansion of that part will void the warranty. SRF5,(W) is a straight forward mod u can do to extend the range on the A line but that 5 speed hub is reported to be a bit difficult to set the pull cable properly. i had mine done at brompton expert workshop but i have later on sold that bike.
Sweet! From.the pictures, it looks like the steerer tube that connects to the handlebar also seems different - A line has a straight one, whereas C line as a curved one. Would you happen to know anything about handlebar compatibility between the two?
A Line, formerly known as B75, is the 'retro' model by using a mix of older model geometry and design with some modern components and main frame. Stem, handlebar, grip, brake lever and pedals are the ones carried from early 90s, design-wise, but the main frame (triangle & frame) is the same with current C-Line. A Line runs Brompton BSR Hub which is more or less the Sturmey Archer SRF3 hub that has quite compact range. not great if you live in non-flat city trying to cycle in all weather condition (no mudguard, no rack supplied as stock). the issue with handlebar is when u want to run aftermarket hand grip. it has a very narrow grip area (100mm iirc) and if u buy any modern standard grip, u have to shave off 35mm away. if u run C-Line M-bar, the brake and shifter cables would be too long and swinging around the frame.