Which cassettes can be fitted?

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mas051

Which cassettes can be fitted?

Postby mas051 » 29 Nov 2004, 5:05pm

I have now worn out my current cassette, and want to replace it. currently it is a seven speed cassette on a shimano RSX freehub. As I would also like to change from my current friction shifters on the down tube to either STIs or Ergos I would also like to go to at least an eight speed cassette. Is this possible on this hub or do I have to get my wheel rebuilt.

matthew

Theo

Re:Which cassettes can be fitted?

Postby Theo » 30 Nov 2004, 8:22am

Eight and nine speed cassettes will fit on a nine speed freehub but are too wide to fit on a seven speed freehub.

A seven speed cassette can be used on a nine speed freehub. If you have a spacer about 4mm wide between the cassette and the spokes your are running seven speeds on a nine speed hub.

You will probably find it is cheaper to buy a new wheel rather than have the exisiting one re-built.

Si Davies

Re:Which cassettes can be fitted?

Postby Si Davies » 2 Dec 2004, 8:37pm

If you want to move to 8speed in steps then you can put an 8spd cassette on your hub if you remove one (probably the second smallest) sprocket and spacer.

You can then use 8spd STI units (more common than 7spd these days).

You can later upgrade your hub to an 8spd and put the spare sprocket back on.

This is how I got up to 8 spd STI from 7spd DT, going to 8spd shifters first, then 8spd cassette when the 7 spd cassette wore out, then replacing the rear wheel when it wore out and putting the spare sprocket back on.

7 & 8 speed chains are the same. 7 & 8 speed mechs are interchangable. The sprocket spacing on 7 and 8spd cassettes is slightly different but if you are careful when setting the indexing you shouldn't have any problems with this extremely small difference, infact when asking Shimano what to do when our 7spd shifters wore out because we could find replacements they advised that we should use 8spd shifters on our 7spd rigs instead.