cassette/chainset compatible?
 

I'm looking at replacing my well worn cassette/chainset/chain and have found a few products I'm looking at buying, I'd appreciate if you could tell me if these will work well together. It's for my 8 speed Specialized Sirrus.

SHIMANO FC-2303 TRIPLE SQUARE TAPER CHAINSET
http://cycle.shimano-eu.com/publish/...-.fc_road.html

Shimano Sora HG50 8 Speed Road Cassette
http://www.chainreactioncycles.com/M...x?ModelID=1864

Shimano HG50 Chain
http://www.chainreactioncycles.com/M...?ModelID=86120

Thanks
James
UK

Should work.

Agree, they should work. Just be sure you get the recommended bottom bracket spindle length to match the new crank. It may not be the same as your current bottom bracket.

Spindle length
 

Thanks, how do I know what spindle length is required, it doesn't say in the specs?

it says 113 mm in these specs:

http://cycle.shimano-eu.com/media/te...9830713926.pdf

if the rings on your present crank are replaceable, why not just change them out?

Simply because of cost, I only really need a new outer ring but to replace it is approx £35 vs £50 for the whole new set which I think is all of better quality than the factory installed crankset. So i'm thinking for an extra £15 just get the whole lot changed.

Are you sure the chainring is worn? If you're making that assumption based on teeth that are shortened or rounded, you're probably looking at teeth that are shaped to aid upshifting. You'll see these specially-shaped teeth on the outer ring (and the middle on a triple), but not on the inner ring. The inner ring doesn't need shaped teeth to aid upshifting since you don't upshift to the inner ring.

My LBS said it was worn and it looks it to me, here's a photo, what do you think?
http://i40.tinypic.com/20a5uf4.jpg

I'm no expert, but yeah, I'd be inclined to agree.