Like most cyclists, I've a growing collection of tools- some useful, some not, some that rarely get used and others that never seem to leave my hand.
The best of these is my chain retainer- which I use when taking the
chain off and stops the chain from springing back when you pop the rivit
out with your chain-breaker. It was completely free and made out of an
old spoke- why not make your own...here's how
Find a spare spoke and a pair of sturdy pliers
Snip off the end and then bend the spoke, using the pliers into this (look left!) shape. Once you've done this, do the same at the other end. Make sure you tidy up the ends 'cause they'll be a bit sharp.
Thats it, all finished- all you need now is a reason to take your chain off! Enjoy!