Help, my gears change on their own!
04-05-15, 06:37 PM
#1
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Help, my gears change on their own!
I have an issue with my 1981 Lotus Grand Prix (yes it is old, but still works almost as if brand new.) When I come to an intersection or to a stop somewhere, when I get pedaling again my bike makes a nasty, loud clang and the rear derailleur puts the bike into the highest gear possible. I am having issues elsewhere on the bike which this gear issue might be triggering. I have found that when I turn the handlebars a certain to the left I see the derailleur move, so there is my issue. But I want to know how I can fix this... I have Sun Tour shift levers, from Japan. Do I need to adjust the barrel adjuster on my rear derailleur or the slack and the position of the cable? I am getting really annoyed and a few times when I need to move fast it changes gears, plus I feel like putting that load on the bike then it wanting to change gears and the sound it makes is going to do some sort of damage sooner or later.
Please do help, and best regards.
Please do help, and best regards.
04-05-15, 06:39 PM
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Have you tried tightening the adjustment screws on your shifters?
04-05-15, 06:40 PM
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@cb400bill No I have not, but it is late where I am, I will try it tomorrow. I'll be back with an update
04-06-15, 09:14 AM
#6
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Are the shifters on the bars? If so, your cable housing/cable is too short. You're probably turning the bars when you start pedaling too, so it is doing the same thing.
If you are using down tube shifters, I am stumped.
If you are using down tube shifters, I am stumped.
04-06-15, 09:43 AM
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Don't mess with the adjustment screws if you are turning the bars and it moves the derailleur. That would be a cable length or routing issue
04-06-15, 10:08 AM
#8
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Make sure your shifters are actually tight enough. There is a little D-ring or screw in the axis of the shifter that you can snug up finger tight to keep the shifter from moving on its own.
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04-06-15, 04:01 PM
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Thank you all for your help, I think @Bradleykd's solution will do it. I did adjust some screws and that didn't do much but I saw his comment and took a look at my bike, so that should work. Thanks again!
