Bicycle Mechanics - Shimano 105 9-speed Rear STI Shifter - Adjustment or Failure

Took bike in to LBS for some maintenance and asked them to also adjust rear derailleur. When bike was returned the small lever would click after a 1/4" of travel with a small amount of cable movement. If pressed to far end and released nothing else happen and the lever would return to that point of first click. By manually pulling lever back to start position there was an immediate click and the chain would move to next gear. The rear derailleur shifting is smooth. It seems tthat shift point moved from near the end of lever movement to the beginning. Is this an adjustment problem or did my shifter fail? Had no prior problems with shifter prior to LBS adjustments.

If as you say, shifting is smooth to all gears, then you are good to go. You post is a bit hard to follow. I don't understand the part about manually pulling the lever back to the start position, that should not be necessary. If you think the shifter is not functioning normally take the bike back to the shop that did the work.

Al

sounds like a dying/dead brifter.. :(

Simple solution would be to tell the LBS to look at it again. Is your lever just sticking? Like Al noted, your OP is a bit hard to follow.

Thanks for replies,

Let me try explain the problem again:

As viewed from seat; right side shifter small lever.

Originally, by pushing lever in full CCW direction, the shift was completed by the end of that motion. I release finger and the return spring would return lever to full CW position.

Now, pushing lever fully CCW, nothing happens except an early click in cycle. Release finger and return spring returns lever partway to where the early click occurred and stops. I have to pull Lever in CW direction and the shift is made. The lever is not sticking; it just that the return spring is not strong enough to force a shift.

The shifter is working but instead of completing shift in the CCW direction, the shift is now completed in the CW direction.

When I took it back to shop they said I needed new shifters. I'm upset because the shifter was working great prior to taking it to the shop and it failed to shift the first time I used it (did not realize it was hanging up). I guess the shifter just failed when they were making their adjustments; was hoping there was some type of adjustment to get it to shift again in the CCW direction.

What I think you should do is flush out the shifter(s) with WD40. Don't be surprised if this fixes the problem. Shimano STI shifters often quit performing due to the factory grease hardening. WD40 does a good job of softening the grease and cleaning out dirt. I've known this to renew several problematic shifters. I simply use the straw to help squirt the stuff into the mechanism. Use plenty.

If you haven't replaced the shift cables and cable housings that could also help shifting performance. The housings are probably more important than the cables. This is also an easy job. You can use the old housings as a guide to cutting the new housings.

But try the WD40 first.

There is only one direction you should need to work the shifters. All levers move toward the bike frame when shifting. I would call that CW for the right shifter, CCW for the left. Spring action should return all shift levers.

Another thing to check for is the cable end in the shifter. There is a small lug on the end of the cable that must be properly seated in the shifter.

Al

Sorry if this appears twice

Al, Thanks for tips.

I flushed shifter with WD40 and it really freed up the levers but still had same problem. Cable ball end was seated in socket. Disconnected cable from derailleur and found it slightly snug in bottom housing maybe due to tight radius? Cable/cable guide on bottom frame looked ok. Since it happened overnight, I suspect some mechanical failure to indexer. I found replacement rear shifers on inet that can purchased separately and going to try to replace myself.

Do you use WD40 as part of regular maintenance on shifters or only when problelms occur?

only when the problems occur. don't forget to use a light oil to re lube the shifters after using the wd 40.