Dura Ace 7700 Group with WH-7800 Wheelset

Hi guys, sorry I just need some of your in depth knowledge.

It's a bit of a tricky one. Basically I have (most of) a DA 7700 group and a WH-7800 wheelset and I need to get them to work together somehow. Obviously I'm going to have to change some of the bits to 10 speed but I want to keep as much of my 7700 group as possible. I know it's not ideal, and I'm not expecting optimal performance, as long as everything run smoothly with no rub I'll be happy.

Obviously the cassette and chain will need to be changed (due to the specific spline pattern) and the RD also. I should be able to keep the 7700 on the front though right? BB, crank and FD? and as for shifters, they'll need to be 10 speed also right? Or can I have 10 speed on the rear side and 9 speed on the front side? (I'm using DT shifters)

Thanks!

THe 7800 hub is the one with the taller splines isn't it? I'd probably just file them down so you can fit a normal cassette on there.

Thanks for the suggestion @macaroon

Has anyone tried this that can confirm it works?

Run the rear DT shifter as a friction rather than indexed?

I did consider that but I want indexed. Would the 10 speed shifter not work with the 9 speed FD? It's only 0.2mm difference in the the chainring spacing isn't it? I could get a 10 speed FD but then there's the compatibility with the 9 speed crankset..

I missed the bit about the down tube shifters.

Yes, just use a 10 cassette and chain with a 10 shifter.

Use your 9 speed cranks, 9 speed front mech and front shifter. All will work fine, pretty sure your 9 rear mech will also work.

BTW, any of the 5600, 6600, 7800, 5700, 6700, 7900 cassettes will work so you're not limited to 7800 Dura Ace.

It's been a while since I've used them, but I'm also pretty sure the 105 and Ultegra 10 cassettes were the same with the exception of the lockring material and spacer material (steel and plastic respectively on the 105 stuff).

Thanks @macaroon, been a massive help.

So 10 speed shifter for the rear and 9 speed shifter for the front? So 10 speed on front and rear wouldn't work? Just because obviously it's going to be a bit hard to find someone selling individual shifters.

Yes, the front will work with 7800 shifters aswell. If you want "optimal" functionality then it's best to use components from the same groupset, but you'll be just fine with 10 speed shifters, cassette and chain.