chain jumping in Dura-Ace drive train
 

I have a road bicycle for 4 years with Dura-Ace drive train and STI. Recently every time I shift down one gear the chain jumps 2 cogs. What is the cause of this malfunction, worned out chain, cassete, chain rings ?


thanks

You could try increasing the tension on the RD cable a litlle bit by using the in-line cable adjuster up by the right shifter.

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