Im shopping for a new cassette for the ole Rincon.
Its originally an 8 speed, so my question is, can i put a 9 speed cassette on it?
Mainly for the conformity, and you can get nicer 9 speeds than 8 speeds.
Bearing in mind im on a budget...
Cheers

As long as you are also willing to purchase a nine speed shifter.

Yeah im pretty much renewing erything, so i am yes.
Thanks.
Is there anything that could go wrong/ i should look out for?

Nope, just get a new chain at the same time and you should be fine.

those 8 speed sunrace cassettes at nashbar are like 5 bucks and work great. Shifters are usually pricey.

Are they any good though DirtPedaler?

Would i have to buy a new rear derailleur to replace the Alivio item that's already on there? Or front deraileur for that matter? They cost a bit.

You won't need a new FD, but a new FD might minimize some chain rubbing unless you know bike mechanics.

I think you do need a new RD because the Alivio is 8s and will not work for a 9s shifter. The next step up in the Shimano line would be Deore which is 9s and you can get those for maybe $25-$35.

Oh also, get new cables and housing while you are at it to optimize shifting.