Originally Posted by Warin
Half worn? The teeth on the contershaft sprocket are hooked... I'd think that chain will be well beyond 5% stretch.
Replacing sections of worn chain with new does nothing for safety nor ware on sprockets... replace the chain - all of it when worn.
Kenny - when the chain starts to go ..it will go rapidly ... replace your chain (and probably sprockets) NOW. Don't wait.
If you want to save money ... replace the chain when only part worn - the sprockets will still be good. When that chain is again part worn - put the old chain back on .. and continue cycling the chains... this way you get more miles from your sprockets. Unfortunaly this is too difficult with "end less" chains - master links are the way to go here .. replace the master links every now and then as a safety measure.
Do you mean clip-style masters? No way I'd run a clip-style master link on the street.