Bianchi Eros Donna--Fair Price?

[Eden]

If your bike shop does suggest replacing some parts, start with the chain. If a new chain doesn't skip on the old cassette, don't replace the cassette yet. A lot of shops will tell you that you need to replace both at the same time, but I (and a lot of other people) disagree. If the new chain does skip at all, replace the cassette at that point.

I think that only works one way - if you replace the cassette you should replace the chain, but you don't necessarily need to get a new cassette every time you change the chain. I know I replace my chain waaaaaaaaay more often than I need a new cassette (in fact I have yet to wear one out, but I replace my chains at least once a year - usually after wet/grit season is over). OTOH if you get a brand new cassette, its best to also get a new chain, as likely the one you have will be worn and may cause quicker wear on your brand spanking new cassette - and compared to a new cassette a chain can be cheap.

[indysteel]

I think that only works one way - if you replace the cassette you should replace the chain, but you don't necessarily need to get a new cassette every time you change the chain. I know I replace my chain waaaaaaaaay more often than I need a new cassette (in fact I have yet to wear one out, but I replace my chains at least once a year - usually after wet/grit season is over). OTOH if you get a brand new cassette, its best to also get a new chain, as likely the one you have will be worn and may cause quicker wear on your brand spanking new cassette - and compared to a new cassette a chain can be cheap.

Good point, Eden.