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bike shifts down but trouble shifting up

Old 03-21-17, 12:57 PM
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AKHIker
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bike shifts down but trouble shifting up

Hi,


Working on an old 18 speed WM bike. It shifts from 1 to 6 perfectly but hesitates on going up from 6 to 5 and 5 to 4. then it works fine the rest of the way.


How do I know if this is the derailleur or shifter?


Thanks
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Old 03-21-17, 01:04 PM
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rhenning
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Cable adjustment. Tighten the derailleur cable adjuster a quarter of a turn CCW and see if it helps. Roger
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Old 03-21-17, 01:14 PM
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AKHIker
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Originally Posted by rhenning
Cable adjustment. Tighten the derailleur cable adjuster a quarter of a turn CCW and see if it helps. Roger




Not cable tension. I tighten anymore and it won't downshift properly. Went back and forth with cable tension but it won't solve the problem
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Old 03-21-17, 01:41 PM
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dsbrantjr
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Being able to upshift or downshift but not both, and being able to switch between the two by adjustment is usually indicative of a cable friction problem. Check/lube/replace your cables, especially the last loop going into the derailleur; don't forget to check under the bottom bracket if it runs there, road gunk tends to accumulate both places..
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Old 03-21-17, 02:11 PM
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Originally Posted by dsbrantjr
Being able to upshift or downshift but not both, and being able to switch between the two by adjustment is usually indicative of a cable friction problem. Check/lube/replace your cables, especially the last loop going into the derailleur; don't forget to check under the bottom bracket if it runs there, road gunk tends to accumulate both places..
^ +1... This is my vote.

Think about it. You can muscle it from 1 to 6, but to go the other way the derailleur has to supply the force. If the cable is binding more than the derailleur spring can overcome it won't shift.

John
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Old 03-21-17, 05:42 PM
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Going from 1st gear to 6th requires no muscle at all and shifts smoothly. it's going from 6th gear to 5 that is the problem-when you are applying force
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