Yes, it is possible that you do not need to order a new BB at all. The BB can be shifted to the right by few mm by placing a spacer or spacers under the drive side BB cup. These spacers have the same size as for the sprocket cassettes, so if you have an old one, you can pull a spacer from there, possibly just filing out the protrusions that may be there to prevent a spacer from rotating. In any case, a bike shop will normally have such spacers and they range in thickness from 0.5mm to 3mm. I usually have such spacers at hand and use them to tweak the protrusion of the crank to the right side. Incidentally, in my case I use the original Brompton crank on the left as it did pot protrude too far to the left but still left a good 5mm for eventual movement of BB to the right. To guide you, here are such spacers on Amazon.

Thanks much for the idea. I didn't think of adding a ring between the BB and the frame.

The snap ring sold with the Brompton 13/16T cassette is 2mm thick, and fits the BB cup to the T in terms of diameter. OTOH, the spacer is 2,15mm and slighly wider, although it can still sit on the cup, just a bit on the edge.

Do you think the snap ring will do?

https://cimg7.ibsrv.net/gimg/bikefor...e915c3b0d8.png

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Edit: No go.

To move the crankset away from the frame, adding a ring will do nothing: For this, I need to a tiny spacer at the end of the axle.
https://cimg0.ibsrv.net/gimg/bikefor...8c22f3718a.png

DON'T DO THIS axle thing. The good outcome would be that it does nothing, the bad that it ruins your crank. For one you are pointing to the wrong side of the BB, but maybe you just did not pay the attention. Otherwise the spacer I suggested must work - it is the standard way of dealing with the issue. The ring would presumably work for a while but the BB is held in place by friction. Putting something flat under its lip yields more surface for the friction to work than a ring. Overall 0.15mm gain in your situation is insignificant compared to the issue - you must leave extra room for wobbling of the rings, crank catch on the BB axle getting worn out over time etc. Maybe you should just get the BB with a longer axle. Still the benefit of playing with the spacers is that 1) maybe you get away with the existing BB, 2) you develop a better judgment what axle length you actually need, 3) if the new BB comes in and is still too short, you can ix it with a spacer, 4) you get away with a shorter axle with spacers than without, limiting the folded size.

The bromopton lifestyle on youtube ¨ PART 5: DOUBLE CHIANSET AND FRONT DERAILLEUR INSTALLATION has good spacer info and under the comments is says ¨I used a Shimano BB-UN55 bottom bracket (118x68mm) and a 50/34T compact crankset, and had no need for spacers.¨

Different cranksets can stop at different depths on the same BB axle, so for one brand/age of a crankset you may get away without spacers and for other you might not. The overreaching rule is to have some spacers at hand and cope with the situation as it develops.

Stopped by the local DIY bike workshop.

Solved.

Thanks!

https://cimg4.ibsrv.net/gimg/bikefor...6d5bf2fb85.jpg

https://cimg3.ibsrv.net/gimg/bikefor...9fcdc9161a.jpg

@Schwinnsta, I cannot answer your PM as your settings apparently do not allow for receiving a PM.

As to the question of the bikegang spring being worthwhile, the short answer is yes. It makes the shift more precise when the cable is at its most loose.

The reason for there being a longer version of the answer is that the spring had a tad too large diameter for the chain stay side and I had to wind it a tad tighter on that end to make it fit. In the end it was not a big deal. Also it is likely that one can buy a stock spring and just cut it to size. I doubt that bikegang does anything else.

@Schwinnsta, again, I cannot answer your PM as you have chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her. With this I reply to the thread that I think you referred to.

The stiffer spring from Bikegang has been an improvement. However, I kicked out the Ti Parts anchorage. As it was bolted stiff to the chainstay it could cause the gear to get stuck in position. I went back to the original Brompton anchorage (pre-2017 version) because it flexes and excludes this kind of stucking. However, for the end of the Bikegang spring to ft, I had to wind that end tighter.

Now, as to the Brompton anchorage pre-2017 vs newer version, I went to the older one because the newer caused at times problems with dirt getting into the overly complicated cable joint there. This led to the issue of bolting the cable on the pusher side. For this, I got the piece below on AliExpress, and it turned out optimal out of different solutions to the problem.


https://cimg3.ibsrv.net/gimg/bikefor...70bf6c3032.jpg
I needed to tweak that piece slightly as it was difficult to thread the shift cable through. I unscrewed the tube for the cable and drilled inside to make the cavity there conical, so that the cable pushed in would find its way to the hole on the opposite side.

I have not been able to find the settings to do that..

no, you are getting it wrong.

see the markings on bb shell L and R, it shows where it should go.
The crankset is atached to RIGHT SIDE of bb shell, you need to put spacers beneth the bb cup on thath side.

you are pointing to left.

You brought it up, and missed the end of the story:

https://www.bikeforums.net/21101460-post56.html

Did it in 1957 ...on my J C Higgins-Puch 3 speed .. added 3 cog cluster to the hub, put on a triple crank ,
3 shift levers for hub & 2 derailleurs.
3 cubed is 27.

no camera phones back then..






:50:

I used to have 36 gear combinations on my commuting bike, and thought it was good, but I got humbled by a recumbent with 105.

"My Quetzal recumbent came stock with 105 ratio combinations. A triple up front driving a 5 speed mid drive with a 7 speed cluster on the wheel.

Dan could use a 10-speed rear derailleur in addition to the 7 speed IGH.

Pinion gear box driving a Rohloff hub wheel ? 18 x 14.=. 252..

We have another option for 3 speed external cogs upgrade.

X3 Unibody Cog set 11/14/17T (it is mostly compatible with sotck parts, hub, tensioner, chain-pusher or DR spring set, etc...), you do need a narrow 11 speed chain and 3 speed shifter. You might also need tensioner washer to bring the tensioner a bit outward snce the smallest cog is closer to frame stay now.

The 11t will make the gear range even bigger and you can use that to finetune chainring size and get close to your ideal gears.


https://cimg6.ibsrv.net/gimg/bikefor...9a92b7fcd7.jpg
https://cimg7.ibsrv.net/gimg/bikefor...2c152ef60c.jpg

This cogset has wrong ratios for the purpose. An ideal increment for a 3-cog set in combination with BWR is 1.57^(1/3)=1.16, while 14/11=1.27, 17/14=1.21 and 1.57*11/17=1.02, the last wasting a gear. A good set is 12-14-16, that gives increments 14/12=1.17, 16/14=1.14 and 1.57*12/16=1.18, nicely spaced out.

BWR hub optimization is not the main focus of this item. Its more to those who prefer external cogs setup and want to expand stock 2 speed (with minimum cost and effort). 11 and 17t are probably the limits to brompton frame without intrusive mods (frame filing or custom extended free hub body).

BTW, bike.gang.uk : Have you thought about releasing a 135mm steel rear rack, as a safe and affordable solution to use a Shimano gear hub?

Or even a rack + wheel package?

And shipped from Europe/US so that import duty is taken care of?

https://www.aliexpress.com/item/33024325243.html

https://www.kinetics-online.co.uk/ca...custom-builds/
Ben Cooper Builds in Steel ..

get a chainring with, or have machine shop make, a counter bore edge around The hole, so bolt head flange settles in,
And/ or whack a clearance dent in the chainstay.

Can you clarify … “To get the right angle for the derailleur I had to use a couple of asymmetric Sram washers that push the cost up. You can get by presumably with one washer or making some substitute yourself.”

This is the washer in question. It is used to refine the angle of the derailleur in the plane of the bike. Its goal is to solve minor not major problems. In my memory, that Sram washer rotates the derailleur 5 deg in the clockwise or counterclockwise directions. Similar washers on Aliexpress correct the angle by 4 deg, again in my memory. That angle may be reduced by some filing.