6000km and a worn chain - is it good for another 2000km or can I expect failure?
My chain is close to the end of its life. I know this, but just having upgraded my hubs/wheels I'd like to be able to put off the outlay on a new chain, rear group, and possible front large chain ring until next month. The chain gauge reads no life left, but the bike still rides smooth (a little bit of sound from the chain, but nothing major). I she good for another 2000km and 4 centuries or am I pushing it too far?
I don't think the chain is ready to fail. The problem is when you run a chain beyond the recommended elongation, the chain will wear the chain rings and cassette and then when you put on a new chain, the new chain will quickly elongate.
I have heard that over the life of the ring gears and cogs that about 5 chains will be used up. So some people by 5 chains when they get new cogs and rings and rotate the chains on the bike so that they can get maximum life out of their systems. I have never done this. It also seems like the cheap chains that I use only last me about 500 miles of hill riding.
The KMC 8sp chain on my road bike has 15,460 miles on it and is only now at the end of it's life. I clean mine in an ultrasonic cleaner and relube it every 650 t0 700 miles.
The only accurate way to measure chain wear is with a ruller.
Chains should be considered a 'wear item' like tires, handlebar tape, and brake pads; it is unusual you would change hubs and wheels before changing a chain. A hub with worn or rough bearings probably has less impact on performance than a badly worn chain. If the chain is not excessively worn (although 6000 miles is much longer than I get out of chains), probably all you need is the chain itself - no need for chainrings, and you may even be able to go without a new cassette.
The smallest sprocket has already been replaced once. So its relatively new. The one next to it (7/8) is original but still looks pretty good. I usually push my bikes hard so parts wear out fairly quickly. Given that my favorite gear sprocket is almost new and the 44t chain ring looks to be in good shape I may just get away with replacing the chain only. But, for now I think that the best option is just to ride it as until it starts to show signs of slipping under load. Thanks for the wisdom.. the guy at the LBS was sure that chains must be replaced at 3000km.