Stronger Climbing with a Brompton 2 Speed

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BromptonFan

Active Member
Hello,

My wife and I have purchased a pair of Bromptons and enjoy them very much. However, we did not take into account the fact that where we live has some light hills. We have not biked in 30+ years so are extremely new to all these considerations. We had to have a folding bike for space reasons in our house.

These hills are roughly 150 feet in elevation and are not super steep. They were hard at first for me, but I feel my strength improving. My wife is 54 years old and is having a harder time. I want cycling to be fun for her and so am trying to see what can be done to save her Brompton.

I know that Brompton offers a front sprocket with -18% gearing. I dont know if this is enough. Surely this is the cheapest way to lower the gear ratios. I'm wondering if there are other options? Can anyone comment?

Thank you very much.
 

CopperBrompton

Bicycle: a means of transport between cake-stops
Location
London
I think it's impossible for anyone else to say, but it's a cheap enough mod to try out.
 

bikegang

Mod before ride, my bike my style...
There is also 40T or less (38?) front chain ring if BCD130 spec.
Rear cog can go up to 17t without filing the frame (19T with filing) ... these are the easiest and cheapest ways to expand gear range....
or
4 speed rear hub kit can go up to 22T by changing the tensioner and wheel ....
Two front chain rings modification also possible
And the ultimate solution of Schlumpf Mountain Drive (50T standard physical chainring can be 20T virtual if gear engaged) .....

60T on this one = 24T if gear engaged. Heel kick to swift gears.

IMG_2614.JPG
 

12boy

Guru
Location
Casper WY USA
You havent said what the current setup is, but in addition to the suggestions above, if you have the newer 130 bcd crankarms you can add a smaller chainring. You have to move it from one chainring to the other with your fingers, but this only takes a minute. (The greasy finger shift) I have a hill that goes up 100 feet in a tenth of a mile and although I make an effort to do it I would find it very hard without the low gear option. I call this 38 tooth chainring Mr Stumpy.
 

TheDoctor

Europe Endless
Moderator
Location
The TerrorVortex
Assuming you have the newer chainset with detachable chainrings, then changing the front chainring is the easiest thing to do. Or fit a cheap double, which is what I have on my one.
Alternatively, you could probably sell the two speed Brommie and buy a three speed for much the same price, which also gives a (somewhat) wider range of gears.
 

Kell

Veteran
I always post this table when anyone asks about gears as it's a useful comparison to see what can be done using standard Brompton parts...

I believe the only differences are the front chainring - either more teeth or fewer.

For comparison, I have the standard 6-speed and there's a hill on my way home that climbs over 300 feet in less than half a mile. I have to use a combination of 1 and 2 to make it up. Both of these are easier gears than a 2-speed with the -19% chainring.

23509505_10154843934676021_3444676570194450348_o.jpg
 
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OP
OP
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BromptonFan

Active Member
Well, I've had my Brompton for a good month or so and I feel my strength improving all the time. Climbing the hills to my home definitely take a lot out of me, and I'm fairly gassed when I'm home, but not to the point where I think I'm going to die. The first few times were brutal.

Unfortunately, my wife is not as strong as I am and it looks like buying her a Brompton was a big mistake. I did NOT do my homework properly. I want biking to be fun for her and struggling up the multiple hills near our home takes a LOT our of her (she's 54).

I'm not certain at all dropping the gears by 18% is enough of a drop for her.
 

Kell

Veteran
Depending on how much you think you would/might lose if you sold it, have you thought about getting it converted to a low-ratio 6-speed? Buy the kit below and a smaller chainring (if you haven't already tried that).

Should give you just under a 50% easier first gear.

It's expensive if you're just going to take a punt on it though...

https://brilliantbikes.co.uk/brompton-wheels/315-brompton-gear-upgrade-2-to-6.html
 
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Julia9054

Guru
Location
Knaresborough
Depending on how much you think you would/might lose if you sold it, have you thought about getting it converted to a low-ratio 6-speed? Buy the kit below and a smaller chainring (if you haven't already tried that).

Should give you just under a 50% easier first gear.

It's expensive if you're just going to take a punt on it though...

https://brilliantbikes.co.uk/brompton-wheels/315-brompton-gear-upgrade-2-to-6.html
Some Brompton shops allow you to hire one. She could hire the 6 speed one and see how she gets on with it first
 
OP
OP
B

BromptonFan

Active Member
Depending on how much you think you would/might lose if you sold it, have you thought about getting it converted to a low-ratio 6-speed? Buy the kit below and a smaller chainring (if you haven't already tried that).

Should give you just under a 50% easier first gear.

It's expensive if you're just going to take a punt on it though...

https://brilliantbikes.co.uk/brompton-wheels/315-brompton-gear-upgrade-2-to-6.html

Thank you for the reply. This kit is from Brompton right? It's not a third party one, correct?
 
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