Changing Brompton chain and sprocket

[Yellow Fang]

I'm thinking of replacing the chain on my Brompton and probably the jockey wheels. Maybe I should change the sprocket too. I see there's two widths of chain, 3/32" and 1/8" and several lengths. This is a bit of a pain. Does it matter which width? I have a three speed hub, but no derailleur, i.e. it's only a 3 speed bike. How easy is it to change the sprocket? Do you need any special tools?

 

[RecordAceFromNew]

Chain selection is covered here while sprocket parts selection is here.

3 speed hubs on a Brompton could be by Sturmey Archer or Sram, the former is more common. It is likely that the sprocket is held in place (as shown here) by a circlip. You might be able to find a pair of normal thin nose pliers to release/install it, but circlip pliers with multiple tips catering for different circlips are readily available for only £3 on ebay.

Sheldon has more than extensive info on SA hubs.

 

[Yellow Fang]

Cheers RAFN