keyven

Derailer Adjustment (Sheldon Brown's explanation)

From what it looks like, it's a matter of setting the bike on the large-large (as in the biggest sprockets? highest gears?) combination without going through the rear derailleur, and making sure there's a full single link (~1 inch) overlap? Not sure if I'm missing anything.

I've never removed chain links before, so I just want to be sure before buying the chain tool and setting on a path to certain doom. I do like the idea of a master link, of which I've never heard of before.

Any advice would be appreciated, thanks.

jur

On your Brompton? You could get away with not removing any.

The chainwheel has half of its teeth engaged on the chain. So remove half the number of teeth worth of half-links, that is, 2 half-links.

If you keep it as-is, you can go back to 44T at any time.

keyven

Really? I don't need to remove any links? That would be great.

Any significant disadvantages like higher likelihood of chain drop?

bhkyte

Trick with chain link removal is not to completely remove the rivot. Else it will not go back in. I start from the back of the chain then I can do the harder part of inserting the rivot back in again with out reaching over the transmission. Off course you can take the chain and swop it around but I prefer to keep it on the biks to keep it clean etc.
Check the link is pivoting and not tight afterwards. If it's tight then push the rivot back a bit further in. Repeat from other side if nesseary.

fietsbob

the chain tensioner will take up the slack , it takes up a lot more when you fold the rear wheel under.

the 2 speed shifter on Bromptons is unique to themselves* .. consult the factory website for that ..

there's online videos and PDF to see.

* it uses the pulley itself, and has flanges on either side of the chain for the |_| fork piece,
fits over those to push them sideways on a wider shaft thru them ..

keyven

So I spent last night taking out the 44T and installing the Shimano 39T Chainwheel and it works like a charm. Much easier to start off and while downhills aren't as fun (quick to spin-out) - that was never my intention anyways - long slopes feel appreciably more tackle-able.

However, bringing it to my LBS for a quick checkup, the tech there says the chain is overlong and cautioned that it should be shortened or risk chain-drop.

DoubleDiamonDog

What? Keyven, how can you like the idea of something that you have never heard of?

Just kidding of course, but getting back to your question, what others say here is likely true - that the tensioner will take up the slack. But it seems to me that the tensioner will be in a different position while riding than the position it would "normally" be in. I believe that if a brompton shop mechanic swapped out your chainring, he/she would remove links. I can't tell you how many, and although I could take a guess, I would check with that mechanic.

keyven

So happens I'm 'that mechanic' The LBS shopkeeper wanted to charge me $10 to remove the extra links but I'd figure I might as well learn it myself, so I can deal with it in the future.

Almost forgot about the master link but when I get a new chain - likely months later - I will add it in.

tk1971

I removed 2 links going to a 39T on my 6-speed Brompton. I used an SRAM 8-speed Powerlink to re-join the chain.

When I left the chain at the original length with a 39T, I couldn't cycle the pedals when the bike was half-folded (chain too loose). Shortening it made it spin like it should.

1nterceptor

It's possible to ride without shortening the chain going from 44T to 39T.
But I think it's better to shorten it. I think I took about 4 links, but I can't
remember for sure.

2013 Brompton DA chainring Ultegra chain by 1nterceptor, on Flickr

keyven

I'm going to order the Powerlink connectors then. Just curious, how are the 7-speed, 8-speed and 9-speed different? Can I only use an 8-speed for my Brompton and why?

I want the gold which is only available in 9-speed.

fietsbob

I favor 3/32 old style Full bushing chains on my 3 speed and rohloff..

derailleur chain now ,, manufacturing makes the inner link so as to form the bushing under the roller out of the steel displaced in making the hole.

good for lateral flexibility , but not as long wearing as the older design.


more "Speeds" in a limited space = thinner spaces between cogs and thinner cogs.. so chains have to be thinner too //

3 speeds allow an even thicker 1/8" chain ..

IDK about the 9 spline 1 & 2 speed or 3x2 speed BWR
maybe cogs out of cassettes will work.. and taking them from a 9 speed cassette will let You use that fashionable color .

chagzuki

The crank spider looks really neat with the black chainring... however with Bromptons I would, where possible, aim for increasing the size of the sprockets as I've found that the chain tension that the deraileur creates makes for very rough tooth engagement/disengagement on sprockets with fewer than 14 teeth.

dynaryder

8,9,10spd cassettes are the same width,the cogs are just skinnier to get more in the same space. Chains and rings are skinnier to match. 9spd link,being thinner,wouldn't ride over cog/ring/tensioner teeth properly,plus there's a chance it won't clip together properly when added to a wider 8spd chain.

keyven

Well I purchased a 9-speed chain for my M6R because it was going cheap on CRC. Seems like I might have made a mistake...

keyven

Can someone pls confirm if a "SRAM Powerlink 9-speed chain connector" will work with a 2013/14 M6R Brompton? Thanks.

fietsbob

the 2, 6 speed cogs are 3/32" thick . a 3/32" chain is aka, (5,6,7) 8 speed . 9 speed and upward chains are thinner..

get an 8 speed chain .. connecting link .. KMC or SRAM.. will be included ..

dynaryder

Given the tightness in the rear tensioner,I think you'll have issues. Best to get the proper chain.

keyven

Thanks I couldn't cancel the SRAM 9-speed chain connector so I guess I'll just have to sell it at a loss. Doing it again with an 8-speed.

dynaryder

Put it in the parts bin until you need it for a 9spd.