Gearing Cofusion

Hi all,

I'm currently in the middle of a build. I have a some knowledge when it comes to bike building but I'm no pro and I'm just a little confused about something and would be very grateful if someone could help out.

I've got half a 9 speed DA 7700 group (BB, crank, front & rear mech and STI levers) which is all ok but this is where it gets complicated. I have a DA WH-7800 wheelset which is 10 speed. What is the best way to configure this? Will putting a 10 speed 7800 cassette + chain work with the 7700 group or do I have to get a 9 speed 7700 cassette + chain with a spacer? Or will neither work?

Any help would be appreciated.

Thanks

You need to match the cassette to the shifters, so if 9 speed shifters you need a nine speed cassette, other combinations will not work satisfactorily. Plus the wheel is 10 speed. So new wheel or new shifters.

A 10 speed Shimano freehub will accept 8, 9 or 10 speed cassettes.

Is not this particular hub 10 speed dura ace cassettes only? due to the different spline configuration.
From the incomparable Sheldon Brown, "Dura-Ace 7800 10-speed freehubs have taller splines than other Shimano models. "

http://www.sheldonbrown.com/dura-ace.html

Apologies: I'd forgotten about them.

I was a little puzzled by your comment, but it still didn't register.

Thanks for the comments guys. So it has to be a 9 speed compatible hub? It wont work like I said getting a 9 speed cassette with a spacer on the WH-7800's?

7800 freehubs have a different spline pattern to regular Shimano ones, so you can only use 7800 cassettes which are 10 speed.

So you either need a different wheel or a 10 speed drivetrain.

Wait sorry yes of course, don't know what I'm talking about. Thanks

Or you can get a 10 speed cassette and just swap out the spacers for 9 speed ones and it could work, unless the largest cogs are rivetted together in which case you're stuffed. I'm not familiar with DA stuff but I've done that with Campag 8 and 9 speed and it's not been a problem.

Thanks for the suggestion @übé®_grübé® I think they are riveted.

Has anyone done this who can confirm it works?

You are in a very niche area, fudging to make things work well will not be easy or cheap, maybe reappraise the whole thing.

You think? Could I not just get 7800 levers? Or would that not work with the derailleurs?

I have a set of 7800 levers for sale

Scuffed but working

Also co-fusion is a Japanese techno artist.

Yes a 10 speed set up will work with a 9 speed derailleur but will not be optimal.

So the ideal option is just to go full 7800...

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