Ultegra Di2 Shifting Problem

carchie86

Hi, I'm a bit of a bike repair novice and I hope I'm not asking a silly question but I'd appreciate a bit of advice with my Ultegra Di2 issue. As I'm shifting up on rear cassette I'm finding that the chain is jumping from the 3rd cog to 1st cog and completely missing out the 2nd one. As I go back down the cassette it does go into the 2nd and 3rd cog but usually after a lot of clicking and delay. Once I'm in the 4th cog it will shift down to the 10th seemlessly.

I haven't fiddled with the indexing on the gears in any way and it was checked over by my lbs on its last service since when it has worked perfectly until the last fortnight or so. The chain, cassette, jockey wheels etc are kept in pretty good order with regularly degreasing and oiling.

Is this is a simple case of my Di2 needing re-indexing or something else causing the shifting problems?

Thanks, Chris

CiB

Why not try indexing them to see? What you've asked is the equivalent of 'my shoes are loose, could they need doing up a bit?'.

Di2 indexing is trivial and something you can do on the move in 20 seconds; it's not as if it's a major task. For a while mine used to lose the indexing when the battery was removed for charging; reindexing it took up the first 100 yards of the next ride. Read up on it, try it to at least exclude it as a cause.

If that doesn't cure it, examine the chain and check that the rear mech moves freely across the full range.

rafletcher

Have a read of the "dealer" manual on setting the rear indexing. DM-UL0001-02

http://si.shimano.com/#seriesList/51

trailflow

Before going into adjustment mode its a good idea to check

the hanger is tight

the derailleur is tight on the hanger

the hanger is not bent

the cassette lock ring is tight

the limit screws are set right

there are no bent chain links

the wheel is seated properly and the skewer is tight