Swapping old cassette to new wheel

[Johnny5]

I'm looking to get a new set of wheels for my Giant Defy road bike, can't really decide whether to get a set of Mavic Aksium or Fulcrum Racing 5.

Anyway, my bike currently has an 8 speed cassette with like a clear plastic disc on the larger end of the cassette.....is this like a spacer? My question is, if I bought a 9 speed wheelset, will my current 8 speed cassette with that plastic spacer thing fit on the new rear wheel as I can't seem to find any 8 speed Mavic Aksium or Fulcrum 5 wheelsets, only 9s and 10s?

Thanks.

 

[montage]

I am pretty sure that this plastic thing is just a guard....doesn't actually screw onto the casette like a sprocket does?...I could be mistaken

 

[Johnny5]

If this plastic disc isn't a spacer, then can you actually buy spacers so that an 8 speed cassette can fit onto a wheel made for 9 speed cassettes?

 

[ianrauk]

it's not a spacer, it's just a guard to stop the chain dropping in between cassette and wheel. You can either remove by taking off the cassette or cut away with some pincers

 

[TheDoctor]

And Shimano hubs are 8/9/10 speed compatable. You get a thin spacer with 10 speed cassettes, but 8 and 9 speed just interchange. Your 8 speed cassette will drop straight on - no spacers required.

 

[Johnny5]

Thanks for the tip doctor. Cheers.

 

[John the Monkey]

Mavic Aksiums may come with a spacer - mine did. This is because Mavic's shimano splined freehubs also fit their own cassettes (which don't need the spacer). On my Askiums, this is a thin metal spacer that goes on the freehub before the cassette.

If you do go for Aksiums, and they do come with a spacer, DON'T BIN IT!