Hello, I'm planning to purchase a custom 6 speed, H handlebar Brompton. Should I
opt for the -12% gearing? I live in Harlem and will be riding my bike up
Amsterdam Avenue btwn W125th and W116th streets regularly. This hill seems
pretty steep to me and I would like to be able to peddle up it without killing
my knees or standing on the bike.

Thanks for your feedback,
Pascale

I have the standard 6 speed gearing and when I encounter hills and I have some weight on the bike the optional -12% would be nice.

Yes. If you encounter any hills, or think you might, the reduced gearing is helpful.

Also, this is not an irrevocable decision - if it turns out you don't like the reduced gearing, you can buy the standard 50T chainset for ~$40-50 and install it; it's just one piece and it will give you the standard gearing.

I did the opposite - went for the standard gearing and decided it was too high and so installed the 44T chainset on my 3spd.

I don't know about your area, but I live in a place with many bike paths that do not have a change in elevation greater than 5% by design, but which also has some moderate hilly areas on the regular roads. The Brompton is fine for the bike paths, but for the regular roads, I wish I would have gotten the granny gear.

This seems to be such a big issue for so many people, I don't know why Brompton hasn't incorporated this into their overall design. For as great a bike as it is, gearing is the one major issue they have never completely addressed. Even on a flat surface I almost NEVER use the fifth or sixth gear, and I'm a weightlifter from a family that has professional athletes in three different sports. Brompton shouldn't just offer a granny gear option, all six gears should be lower.

Numbers... the 3 crankset menu choices are 54(+), 50(std) & 44t(-)..
external cogs on 6 speed is a 13-15t pair.

help with the math ..
https://sheldonbrown.com/gears/internal.html

I love my H6L (std gears) which I bought at the LBS but if I were to order one I'd opt for the -12%. Houston is flat in the main but it is windy around here so a little less gear helps when battling a headwind.

My wife and I got the -12% reduced gearing. The bike store, in Victoria, BC, commented that not only does the reduced gearing make sense for the hilly landscape, but also that they found that the gearing matches what most people expect when pedaling. Eventhough there are no real hills where we live, I've found the reduced gearing really appropriate for stop and go city travel and when cycling into the wind.

I have a MR6 with 12% gear reduction and I have to say it is useful when riding the hills that on the Westchester County trails. I can also keep up with most people on the flats as well. Of course I have to work harder but it helps me get my HR up which is why I'm biking anyway.

I went for the standard gearing but will probably change to the lower some day. I have only used the sixth gear once, and that was downhill.

Why don't you contact David at Bfold to see if they will rent to you for a test ride before buying. It may give you the best chance to test both gearing set ups on the hill you need to traverse.