Cc Tensioner

Hi folks, my TBS has developed a rattly noise at low revs, sound quite agricultural at times... Still goes well... What sort of mileage would a tension last? I'm on 38k and I'm sure noise wasn't there at 36k..(if it was it was quieter).. Also I've put in new ebay pilot jets which were slightly bigger, recommended apparently, and not really set carbs other than reassembly settings.. Last question.. Is it OK to just fit new spring and washer, £13 off ebay to my tensioner... Or is it wise to fit whole thing..? Anyone's experience would be welcome.. Thanks

 

Cheers...
Alternator bolt?... What? Loose?

 

Hi all thanks for the advice, I replaced the tensioner spring, it was about 8 or 9mm longer than outgoing spring... Engine is definitely quite but there is still a roughness at idle... If it were a car I'd say it sounded like gearbox chatter.. I've since learned that there is a balance shaft with a needle roller bearing each end. Anyone had experience of this shaft...?