Bicycle Mechanics - Shifting issues w/ VIDEO examples
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06-01-09, 11:49 AM
These vids were taken this morning to provide examples of my mysterious shifting problem. Please view them....and maybe I can get to the bottom of this issue once and for all!
The problem: Delayed shifting, or no shift at all, or a double shift. Can set cable tension to shift either UP or DOWN, but not both. Video #1 details the struggle I go through to make a simple shift:
YouTube - No Zip
The temporary solution: If I route the cable under the rear axle and secure it with zip-ties...everything works. Video #2 is a good example:
YouTube - With Zip
The LBS tried twice to repair the problem....all cables and housings are new.....Ultegra group is fairly new and was removed from my LeMond in perfect working condition.
06-01-09, 12:11 PM
My first thought is still my last thought. I think its a cabling issue especially if it works fine when routed under the QR axle. Just because the cables and housing is new doesn't mean it will work flawlessly. Sometimes the cables can be pinched at the end causing excess friction causing the delayed shifting. Another thing to check is the Derailleur hanger. This can cause so many problems shifting. If your hanger is good it can also be a bent derailleur. But like I said, I think its friction in the cable housing in the back :(
06-01-09, 12:17 PM
Old housing or new housing, the problem is the same....the solution is the same too. That's what leads me to believe it may not be a friction issue. In fact, it seems I would be increasing friction with the tighter bend, but that's what makes it work!
Silly question......how do I check the hanger?
06-01-09, 12:22 PM
Something else I noticed...
When the zip-ties are on, the position of the derailleur moves forward....or "up" if you will. I associate this with B screw setting, but w/o the zip-ties and w/ the B screw set to the max "up" position, I still have issues.
Thought this info might help.
06-01-09, 02:26 PM
to check the hanger you need a tool like park tool DAG-1 or DAG-2. your lbs should have one of these in their shop. it be a few bucks for the service.with today's bike and having 8 and more gears, it doesn't take much to be off and give you a problem like you are having.
06-01-09, 06:18 PM
Check the hanger alignment.
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