Problem with Deore lx rear derailleur
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Problem with Deore lx rear derailleur
The other day I had a problem with the shifting on a Deore LX rear derailleur. I figured out what was wrong and thought I would tell you all about it in case you might have a similar problem in the future.
I took a 94 GT Karakorum home from the Bike Exchange to work on and found it in pretty good condition except the rear derailleur cable has removed and the trigger shifter was gummed up. A little wd40 loosened up the shifter and a new cable was installed. The bolt that holds the end of the cable on the derailleur was missing so I looked in my spares box and found a 1/2 hex head bolt to replace it. Everything was tightened and looked o/k until I tried shifting through the gears. The low and high gear on the 8 spd cassette were not right somehow. No matter what I did I couldn't get it to shift onto the largest cog and it made noise on the smallest like it was trying to shift .
If I undid the cable from the derailleur it would shift onto the large cog and the small one and did not make any noise.
I fiddled with it some more , Tweaking the adjustment barrel on the cable, but whenever I tightened the bolt down on the cable I had the shifting and noise problem .
Finally, I figured that something was interfering with the movement of the derailleur. I set the bike so I could look at the derailleur up close while moving it back and forth.
What I found was that the bolt was about 1/8" too long . It was hitting the parallelogram hinge when it was moved to the extreme either way. When I had taken the cable off I had loosened the bolt enough that it cleared everything.
I took it off and installed a 1/8" thick washer then tightened everything down and now everything works fine.
I took a 94 GT Karakorum home from the Bike Exchange to work on and found it in pretty good condition except the rear derailleur cable has removed and the trigger shifter was gummed up. A little wd40 loosened up the shifter and a new cable was installed. The bolt that holds the end of the cable on the derailleur was missing so I looked in my spares box and found a 1/2 hex head bolt to replace it. Everything was tightened and looked o/k until I tried shifting through the gears. The low and high gear on the 8 spd cassette were not right somehow. No matter what I did I couldn't get it to shift onto the largest cog and it made noise on the smallest like it was trying to shift .
If I undid the cable from the derailleur it would shift onto the large cog and the small one and did not make any noise.
I fiddled with it some more , Tweaking the adjustment barrel on the cable, but whenever I tightened the bolt down on the cable I had the shifting and noise problem .
Finally, I figured that something was interfering with the movement of the derailleur. I set the bike so I could look at the derailleur up close while moving it back and forth.
What I found was that the bolt was about 1/8" too long . It was hitting the parallelogram hinge when it was moved to the extreme either way. When I had taken the cable off I had loosened the bolt enough that it cleared everything.
I took it off and installed a 1/8" thick washer then tightened everything down and now everything works fine.
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