Downtube shifters question

Dustine

Can a set of old downtube shifters be used with a new ten speed drive train???

Im building up an old steel frame and purchasing some bits, reusing others. I cant afford all new shifters, and have a set of old campag none indexed downtube ones . The new crankset is 10 speed, and i have an old (8 speed??) rear mech that i might reuse. I suppose the jockey wheels might be too wide, in which case i will get a new mech. I will be building a new wheel and buying a new cassette, so that can be 10 speed. Will this whole bodge work???

aracer

You could use non-indexed shifters if you want. Not sure I'd fancy it that much with 10-speed though - put my 8-speed shifters into friction mode yesterday as the indexing was a bit out and it was making noise, but it was a bit of a pain.

You can actually use a 10-speed crankset with 8-speed, which is what I'd recommend if the rest of your proposed upgrades are being driven by that (if necessary with a 9-speed chain, but it should still work with an 8-speed chain).

3leggeddog

Cant see why not

The rear mech will cope with the range, as will the downrube shifters. The gears will be closer together thats all.

Remember to fit a narrow 10sp chain and all will be fine. Downtube shifters make settin up easier as theres no indexing to worry about

Dustine

Its a bit complicated at the moment. The frame is an old low-pro model. Im going to be running low-pro bars, but no TT bolt ons, at least for now, so i cant run both bar end shifters AND the brake levers which go in the ends of the bars. Which leaves down tube shifters. Its all coming together a bit at a time, because i havent bought the bars yet to know whether the old aero levers i have will be ok or not. Its being built as and when funds allow, in combination with what i have laying around. All good fun, but more difficult than just buying a bunch of bits new....

aracer

Alternatively, if you plan on sticking with the DT shifters, you can of course get 10-speed indexed ones, though that means spending money!

pliptrot

With 6 speed friction worked just fine. 7 & 8 speed systems have the cogs 5mm apart, which is manageable by feel. With 9& 10 speed, well it gets really delicate -if you can imagine 10 speed spacing is a little over 4mm between cogs, you've lost about 20% of your cable pull per gear, which means each tiny adjustment is in fact a much larger proportion of the distance between cogs. Technically it's do-able, but it'll drive you nuts. Good luck.

Monty Dog

In theory it will work, but it will be fiddly in practise. You will be able to run a 10 speed chain on your 8 speed mech, but it will be pretty sloppy so trying to get accurate shifts might be difficult as you'll need to over-shift and then adjust to get ithe chain to run cleanly.

Fred Steele

I use 8 speed with old Campy friction shifters on my winter bike (which was a 6 speed before I spread the frame and converted it). I got used to it in no time and I love the reliability and zero-maintenance needs of friction. If you set the friction level just right you should be able to just "tickle" it up one gear in a single stroke every time. Changing down accurately is harder, I usually have to go down a bit too far and then come back up a bit, going easy on the pedals until it's silent and smooth, but I assume you're not going to be racing on this bike anyway. I do 30 miles every day with no problem, and my balance has improved too.

Dustine

Ok, ive got some of the way their. The crankset isnt installed so no chain, but the shifters and mechs are in. I can now friction shift the mech onto the 2nd from largest sprocket, but not the largest, as it will cause the mech to hit the spokes. Are 10 speed mechs narrower??? I mean the bit that holds the jockey wheel, is it narrower, to get to the innermost sprocket without hitting the spokes???

Fred Steele

When I got my 8 speed cassette it came with a spacer that I put onto the freehub first. This brought the largest sprocket away from the spokes slightly. I was also very careful to set the low limit screw so that the chain just gets onto the largest sprocket and no further. Otherwise I'd be in danger of chopping through spokes! Luckily, the cage (which contains the jockey wheels) of my old Campy 980 derailleur gives enough clearance.

If I were you I'd set your low limit screw to the lowest safe position without a chain on, watching the clearance between cage & spokes as you turn the wheel slowly. Leave a safety margin for flex, etc., then esti-measure the distance between the line of the bottom jockey wheel and the current line of the largest sprocket. Try and get a spacer or 2 of this thickness for your freehub. Make sure your cassette lockring will still be able to screw on enough threads if it's moved outward by this distance.

Good luck, and I can't guarantee it'll all work!