Spotlight on the chain


When to replace the chain?

Willi Mindak, Apr 99:
When is it time to replace the chain? Is the damage to sprockets/ chainwheel a result of a worn (lengthened?) chain, or is the chain worn because of wear to sprockets and chainwheel? Should one replace the chain more frequently, or is it best to replace the whole drivetrain at the same time?

Chain lubrificants

White Lightning

Chain falling off while riding over bumps or while unfolding

It's not often reported, but is no fun to put the chain back.

What to do when it happens

Why it happens and how to avoid it

  1. Is the chain lubricated? Check for stiff links.
  2. Phil Gough, Jul 1999:
    I have known mud and crud buildup on and around the sprocket to lift the chain up off the teeth of the sprocket. But you have to really neglect cleaning the bike to get it this bad.
  3. Chain is strechted or simply too long for the current chainring and sprocket. When the Brompton is unfolded, the chain tensioner arm shoud be almost horizontal, slightly downwards. Replace the chain if it is stretched 1% (unless you have your own chain replacement policy). Check if you could remove a link from the chain while the bike is unfolded (the maximum chain length required is when you start folding the rear wheel assembly).
  4. Can the chain tensioner (the arm with idler pulley) rotate freely, apart from the spring force?
  5. Is the chain tensioner properly seated? Are all chainwheels in line? Sprocket spacers assembled in the right order?
  6. I've replaced the standard 13 tooth sprocket with a 14 tooth (see Spotlight on the rear sprocket - Replacement rear sprockets). Now the idler wheel is so close that it seems the chain cannot jump off there at all (but someone claimed it did). I couldn't notice the slightly reduced gearing, which really was too high anyway.
  7. David Edge, Oct 1998:
    If all else fails you can buy 'half' links to tweak the tension.
  8. Phil Neff, Nov 1999:
    After dirtying my hands numerous times, I decided to let Channell, the USA distributor, see what he could do. Though he could see nothing amiss, he replaced the chain and chain tensioner and I haven't had the problem since. Channell charged nothing!

Chain skipping in snowy/icy weather

Narrowing down to 1/2 x 3/32 chains?

Super link in the chain

Richard Lighton, Jun 1999:
The instructions on chain replacement say:
"The joint in the chain must be made without using a link/spring clip."
Is there any objection to using something like the Craig Superlink?

Guarding the chain from road spray or yourself from greasy chains