Complicated question on indexing!

[troutmask]

I am presently rebuilding a touring bike on an old frame.
I have had a new real wheel made up for this (Shimano Tiagra hub). I happen to have a 8 speed SRAM 11-32 cassette (hardly used) which I intend on fitting, I also have a brand new SRAM 8 speed chain. I am also fitting a Deore XT rear mech. The bike previously had a 7 speed set up with indexed shimano shifters on the down tube.
I realise that these shifters won't index with the new system but will have to be used in friction mode. The down tube indexed shifters I see are all 9 speed and I assume won't work with a 8 speed rear. Eventually when both the chain and cassette wear out I can fit a 9 speed cassette and chain. In the meantime should I..
Just use the 7 speed shifters in friction mode, in which case will they work OK?
Buy some 9 speed shifters and use them in friction mode?
Or does anybody know where I could get a braze on 8 speed down tube indexed shifter?
Any other suggestions, I am not splashing out loads of cash for the expensive combined brake and shifter things and don't like bar end shifters in case anybody suggests that?

[Si]

The 7spd shifters should work OK in indexed mode with an 8spd rear end. Although there is a slight difference in the cassettes it's so small that a careful bit of setting up will have it working well. I run one or two of my bikes like this with no probs.

[troutmask]

Thanks, I will try that until the move to 9 speeds at the back. I thought it would run out of clicks? I have indexing on my commuting bike and a mtb but never had it before with downshifters so find it a bit confusing!!! My wifes bike has a 5 speed sti changer on the stem which works really well, not seen many of thee pity they didn't catch on as it always seemed a good place for a shifter, although I am sure their must be some technical reson why you don't see them much.

[georgew]

I'm reasonably sure that DA downtube shifters will work 8 or 9 speed. They use a washer I believe to achieve this. Could be wrong of course.
When the shifters you have are in the friction mode it makes no difference at all to the rear derr. whether these are 7 or 8. They will work anyway.
Myself I'd go ahead and do this and forget friction levers as it hardly seems worth the trouble.

[PW]

Another possibility
Campag 10 speed Ergos. They'll index the 8 speed perfectly when set up normally. When you change to 9 speed the rear cable has to be altered slightly, instructions on CJ's Shimergo pages or at www.hubbub.com
If you decide to move on to 10 speed there's a gadget called a shiftmate.