The shop it likely to be technically correct. But, remember they rightly aim to get the bike working as best it can and that part of their judgement must be in how soon you're likely to be back (either complaining or spending more money) if they do something that will give a slight or temporary improvement.
Depending upon the condition of your drive train, there may be other options of you're prepared to do the work yourself.
The shop it likely to be technically correct. But, remember they rightly aim to get the bike working as best it can and that part of their judgement must be in how soon you're likely to be back (either complaining or spending more money) if they do something that will give a slight or temporary improvement.
Depending upon the condition of your drive train, there may be other options of you're prepared to do the work yourself.