Suntour Accu-shift 2000

In article <[email hidden]>, [email hidden] says...

Quoted message said:

I've got a road bike with 6-speed DT shifters and problematic rear shifting. It shifts perfectly
from large to small, but when going the other way the chain will move 2 cogs per indexed click and
then drop back down one cog as soon as you release the shift lever. If I adjust cable tension so
it shifts up properly then it hesitates the other direction. Nothing appears to be bent, damaged,
or broken.

It's adjusted too far towards the larger cogs. Suntour's index shifting was different from
Shimano's, in that you had to adjust the final positioning yourself after making the shift --
there's no float in the pulley.

When it's properly adjusted, you overshift very slightly, then let it drop back into the detente.

Quoted message said:

2 things I've noticed that I've never seen before: 1) the shifter has a little "switch" on it,
presumably to change it from indexed to friction, but both positions result in indexed mode with
no discernible difference. I disassembled the shifter and can't see what the heck this is supposed
to do. The indexing parts look brand-new.

Suntour had shift levers that would index on two different rear cog spacings, "standard" and
"ultra". An Ultra-6 freewheel fit six cogs in the width of a standard 5-speed freewheel, so it
needed less cable pull per click than standard spacing.

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