Shimano STX jumps 4 cogs at a time



Someone gave me this Trek mountain bike, and it was missing the shift
cable for the rear deraillier. I replaced the cable, correctly I think.
It has the twist type handlebar shifters.

Now, when I shift from gear 7 to 6, the chain jumps from the smallest
cog to the 4th cog. Another click and it goes to the 7th cog. I have,
of course, turned the 3 adjustment screws in all sorts of ways, but
that doesn't help.

What could possibly be the cause of this?

I don't think the deraillier is bent. In gear 7, the two idler pulleys
seem to be hanging straight under the smallest cog.

Any help appreciated.

Larry in Decatur
 
[email protected] wrote:
> Someone gave me this Trek mountain bike, and it was missing the shift
> cable for the rear deraillier. I replaced the cable, correctly I think.
> It has the twist type handlebar shifters.
>
> Now, when I shift from gear 7 to 6, the chain jumps from the smallest
> cog to the 4th cog. Another click and it goes to the 7th cog. I have,
> of course, turned the 3 adjustment screws in all sorts of ways, but
> that doesn't help.
>
> What could possibly be the cause of this?
>
> I don't think the deraillier is bent. In gear 7, the two idler pulleys
> seem to be hanging straight under the smallest cog.
>
> Any help appreciated.
>
> Larry in Decatur


Sounds like it isn't attached properly to the RD anchor bolt or the
cable isn't in the shifter correctly. . Trundle on down to a bike shop
and have then take a quick look.If you didn't install the cable
correctly into the shifter, it will not work. Older gripshift has the
cable loop around the innards and it must be correct.
 

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