Brompton 2 to 3 Speed Conversion

Hello, anyone has tryed this kit, for the after 2017 shifter?
https://www.brommieplus.com/portal_c1_cnt_page.php?owner_num=c1_343119&button_num=c1&folder_id=81499&cnt_id=823078&search_field=&search_word=&search_field2=&search_word2=&search_field3=&search_word3=&bool1=&bool2=&search_type=1&up_page=1

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Group buy?

Or could be cheap and just group buy a single unit, then send it to someone with a 3d printer to copy and share at cost price?

I was under the impression that 11t-17t was the widest range for some reason. A 3-speed shifter plus 10 to 18t would be great.

Presumably you need the whole kit to reach the 10t to 18t range?

I have a 11/14/19 and no problem going to the bigger cog.
Just "eats" a little the triangle.

The problem is that ir does stops in the 14 cog. Goes from 11 to 19, that's why I need the 2 shifter converti on in to 3.
Will post updates.

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That's interesting. Did you just put 9 or 10 speed cogs and chain on?

Are the BP kits just stock 9/10 speed parts plus the shifter mod? I don't get why they are so expensive.

Well i have bought one integrated 19/14/11 cog. I have a 10 speed chain.
Yes it is a little expensive. The integrated cog was 50 eur.

Is the drive train a lot quieter too?

The stock 2L drivetrain is very noisy I find.

That's because the pins of the chain abrade the plastic dork disk when running in the lower gear. Cut away the disc (leaving just the centre, as that is required as a spacer) and it'll run much quieter. Silent, in fact.

I dont notice any noise change.

Hello, wondering if you did get the 3 speed shifter?

Think I'll get the whole kit. I've had enough of the Brighton hills on a 2 speed.

Hello, yes I did got it, but stil don't have the pretended result. The shifter has little play in between gears and doenst goes from one side to the other. Not a fluid movement.

Do you think that's because you have a 10 speed chain? I'm just reading the description, they seem to think it works best on 11 or 12 speed systems.

Do you think there's any benefit in this conversion versus just getting a SA friction shifter instead?

well dont know if the 10 speed cog is the problem, doenst seem the reason, but i would always prefer the standard shifter in case it works

I had a conversation with someone on Reddit who had success using a 7spd shifter. This one:

https://www.decathlon.co.uk/p/7-speed-derailleur-shifter/_/R-p-311712?mc=8555779#zoom=opened

I might try that with 10/11spd cogs and chain and see what happens.

Seen a few people using a remote shock lever as a 3 speed shifter:

https://www.youtube.com/watch?v=Ic7FgPfz2qA

Very nice looking shifter, but how is it indexed correctly for 3 speed? Do the cogs need shimming or something?

The Brompton chain pusher springs hard against the limit screws in the outer positions, so you just have to get the middle position correct.

So it may just be a case of shimming the whole cog set out (if necessary) and just resetting the limit screws?

Hello again, how did you get on with your 3 speed conversion in the end?

I've finally installed 12t - 15t - 19t cogs and a shifter, but now the issue I have is the chain rubbing on the chain tensioner assembly when in the high 12t gear.

I could file a couple of mm off it, but I wonder why this is happening? Maybe the stock spacer I used between the 19 and 15t is too thick?

Anyone got a copy of the original instructions linked in the first post on this thread (as the link no longer works)?