new wheels and/or cassette

Mint Sauce

as the title sugests, thinking of getting new wheels and/or new cassette, not looking for top of the range, but would still need to be decent spec, and just need some tips/advice on replacing/fitting/compatibility. have had my bike about 4 years, an obrea larren (entry level bike), doing a lot more training this year, and doing 2 or 3 events as well (sponsored runs).

currently have a 7 speed cassette, and not overly struggling with the hills but would like them to be a bit easier maybe, and thinking of upgrading to an 8 speed, would be quite confident at having a go removing and re fitting the cassette, but does upgrading my cassette meaning i have to replace anything else, ie would i need a bigger hub, would i need to do much with the derailer apart from maybe retuning, ie would i need to replace anything else,

as for the wheels, is there much of an compatability issue, would i need to consider a different hub size if i was to go for 8 speed instead of my 7 speed, and how worth while is it spending up to 300 yoyo on a new parts on a bike that cost about 600 yoyo a few years ago.

bcmf

8 speed needs an 8 speed rear mech if you have index shifting plus youmay need to upgrade your brifters.
As regrads rims/wheels.Mavic Kysriums are pretty bombproof for the roads we have.

Gavin

You'll need a new shifter alright if you have indexed shifters?

The derailler should be fine.

You may need to modify the hub when replacing the cassette. More info here
http://www.sheldonbrown.com/speeds.html

(ps. if you happen to be looking for 8speed shifters, I have some sora ones you can have for a nominal fee)

Mint Sauce

not sure how bout this, but looking at around at alot of the wheels, they say their comatable with M10 cassettes, further reading on this my undestanding is this means 8,9, and 10 speeds, if i was to stick with my 7 speed cassette, looking at the sheldonbrown site, shoud i be ok with with my current system if i was to use spacing, excuss my lack of knowledge on the more tecnical side, but does this mean adding space between the sprokets or using a spacer between the cassette and the wheel on the hub, and can i still leave everything else unchanged

Gavin

Yeah you could keep the 7sp cassette with the spacer. The spacer goes in between the cassette and the hub.

Mint Sauce

so i've being doing a little more reading on this, and still thinking of the new wheels, still not sure though about buying new parts that are almost worth a third of the orginal cost of my bike, plus on a frame thats about 4 years old

will stick with my 7 speed, but any of the wheels i've looked at, most have 10 speed hubs, i know the spacer issue has already been discussed here, and on viewing the sheldonbrown site it states you need a 4.5 mm spacer, but looking at wiggle and chain reactions, they sell 3mm spacers, with a discription of using them for for my sinario, ie 7 speed on an up to 10 speed hub



now i know i could just get a local bike shop to fit it for me, but would like to know my self how it goes together and increase my own knowledge