Rear mech trouble?

[Dr.Robotnik]

Yes, I got caught by the 8 speed spacer trick the other day - on a set of Mavic wheels. It's really thin, not some big 3mm+ thing like putting a 7s onto an 8/9 freehub.

Never seen one before either :shock:

^ What he said

Now I do have a 9 speed chain but will it be compatible with the bloody chainset !?!? :shock:

I am pretty sure you don't have to worry, I believe the teeth dimensions are the same between 7, 8 and 9 speed, the only difference is the spacing between the cassette cogs. Hence the need for a smaller chain when 9 cogs are crammed onto the freehub. Otherwise it's all gravy.

Let us know how you get on.

 

[FluffyChicken]

iirc, my 8 speed cassette M737-c (may not be 737 but not going to go look it up, 8 speed 'compact' XT, ~first one) has a spacer behind it.

Older hubs like the M900 8speed of course (e.g mine) I think must have needed this when running the compact cassettes (11 tooth) else they would wobble around.
I'm sure mine is quite thick though. either it is what I had and I fitted it and it worked or it was what I needed/came with it. I only noticed a month back while cleaning it from the 15years of grime, though hit seems to match in well with the m900 colour scheme.
M900 was 12-xx remember, only later was compact introduced.

I could well be wrong and next time I go look nothing is there at all, lol.

 

[daj]

Back again!!

Setting up another rear mech, All my reading and reference explains index going up the cassette but what do you do if its fine going up but when dropping the chain back down it does not want to on a couple of the changes?

And when setting up from the start (before tightning cable up) where do you have the barrel adjusters ... Wound in....wound out ...in the middle somewhere?

Ahhhh the joys of learning!!

 

[hamster]

If it won't go down the cassette to a smaller cog - and assuming it's not some perversion like rapidrise - then the cable is sticky. Try new outers as a long-term fix, greasing or oiling the cable for a quick one. Check for kinks in the outers first though.

I set the barrel adjuster all the way in, then unwind it one turn. Usually the problem is that the cable is too slack when clamping it , not too tight.

 

[stew-b]

or you could have set too much tension on the cable,screw it in half a turn at a time,see what happens.