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[Closed] Can't index gears
I've got a gear syncing problem. I have 9spd Dura Ace downtube shifters on my winter road bike. I'm running a 9spd brand new Sram 13-32cassette with a brand new Sram 9spd chain. I'm using a Shimano 105 long cage rear mech. Trouble is I cannot for the life of me get the gears to sync. I will get the 13-14-15-16 to click across ok, but as soon as I get closer to the low gears it won't sync at all. I adjusted the B screw so the top jockey wheel is 5-7mm shy of the sprocket. Bizarrely when I look at the derailleur from behind the rear mech appears to be lined up perfectly with the sprocket yet the chain doesn't want to sit still on the sprocket. There's obviously not much cable friction because it's a downtube shifter, in any case the cable inner and outer are near new. So I'm wondering what on earth could be the problem. I'd love to try some other 9spd shifters but they're like rocking horse sh*t.
Anyone got a clue?
I presume it's a 9 or 10spd rear mech rather than 11spd?
Is your mech hanger straight?
Mech wear would be my guess, and is it meant to work with 32? Chain length?
Nothing to go wrong with shifters but it is all mysterious.
Classic symptoms of a bent hanger, shifts fine at one end, gets progressively worse towards the other. There may be other issues too, but there's no point in trying to solve those if the hanger's not straight to begin with (assuming your wheel is seated in the dropouts correctly, obviously).Check it with an alignment tool,just looking at it isn't enough.
I'd also suggest getting the hanger checked for alignment. If someone comes to me with gears that aren't shifting right, its one of the first things I check.
An aside, always index from the middle.
If gear 5 of 9 is perfect you split any imperfections half and half in each direction.
Won’t help with a truest bent mech/hanger, but one that’s just nudged a little.
Obviously make sure you do the limit screws carefully.
I had this issue on mine - same set up. it wasnt a bent hanger (never had this).
I did as someone else has suggested - start with the limit screws. The DT shifters seemed to be more sensitive to that. get that really dialled in, then B-Screw then the index in the normal way (although starting in the middle might not be a bad shout).
One last thing - check that the little bit of outer is seated in the ferrule correctly - I has this once where it wansnt all the way in and caused something similar.
No harm in checking them, but limit screws cannot affect shifting other than to top and bottom sprocket.
Good job it's not Dura Ace 8 speed as that only works with the same components - won't work with any other 8 speed.
No harm in checking them, but limit screws cannot affect shifting other than to top and bottom sprocket.
Well, if the chain starts in the wrong place as the cable gets pulled through it will be off-set a little more each time.
Well, if the chain starts in the wrong place as the cable gets pulled through it will be off-set a little more each time.
If you set the indexing not to work, yes.
Have you detached the cable from the derailleur at all during this process? If so, check you've put the cable back on the correct side of the clamp.
Check the cable for kinks inside or near the outers. Broken plastic ferrules have caused problems for me in the past too. Diagnosis over the Internet is hard because there's loads of little errors it could be!
Well, if the chain starts in the wrong place as the cable gets pulled through it will be off-set a little more each time.
If it starts in the wrong place it will be out by the same amount on each shift.
Have you had the pulleys out of the cage and accidentally transposed them, the top one 'floats' to accept chain sway? Does micro adjust on derailleur make no difference ? Is the derailleur cage straight ? Is this a set-up you've used before and it worked ok then? Would a wolf tooth style drop hanger help with clearance? Is the chain length sufficient for the cogs covered? Apologies if you've been through all this.