First Bike

Clingy

I have been told by a knee consultant to ease back on my running and mix it up a bit with cycling and swimming. I must admit that cycling has never appealed to me but then neither did running and I am hooked on that now! So I intend to give this a good shot and start with a reasonable bike. Of all the various types of cycling, cyclocross appeals to me most. I have been to a couple of events and enjoyed watching. However, the intention of a bike is not just to compete but also to keep fit/active. My plan was to get a cyclocross bike and also use it on the road.

Now this is where things start to get confusing for me. Trying to decipher all the jargon and technicalities is daunting....it's like learning a foreign language! My plan was to buy a Cannondale CAADX 105 or Ultegra and then some spare road wheels..or wheels with road tyres. However I am told by a retailer it is "dangerous" to have a worn chain on a new cassette. Clearly with my proposed method the chain will wear quicker than the two cassettes if I keep swapping.

I would welcome comments and suggestions as to how you guys do this (please don't suggest two bikes...my "finance committee" would stop that). Please answer in simple terms as I am a total newbie

Thanks

tgotb

The retailer is very nearly talking rubbish. I have 5 or 6 wheelsets that I regularly swap around between 2 CX bikes, and less frequently onto my commuting bike, and everything is fine. I also swap cassettes on my road/TT bikes the whole time; again, no problem at all.

What actually happens is that as your chain wears it gets slightly longer. If you replace when the elongation reaches about 0.75% (you can check this with a very cheap gauge) you'll probably be able to get through 3 or 4 chains before the cassette needs changing (longer if you're using multiple cassettes). You'll know the cassette needs changing because, when you fit the new chain, it starts slipping in your "favourite" gear. So long as the chain elongation is less than 1%, it'll be fine with any cassette in good condition. In my experience, a chain is good for 2-3,000 miles on road; I replace once a season on my CX bikes even though the measured elongation is negligible (actually, I'm tight, so I recycle them onto my commuting bike).

What might be an issue is if you ride with the same chain/cassette combination for a very long time, until the elongation reaches (say) 2%. Once the chain gets past 1% it causes increased wear on the cassette, and the teeth will change shape to suit the longer pitch of the chain. At this point, swapping in a brand new cassette probably would be problematic. There again, so would changing to a little-used sprocket on your existing cassette!

Summary: Buy a chain checker, replace your chain when elongation exceeds 0.75%, and all will be good.

ugo.santalucia

It's not dangerous. A new cassette with a worn chain might make a bit of noise... just sing while you cycle and you won't hear it