pinking
 

ive got a 86 ten with (i belive)a genuine 9,000km on the clock.when you accelerate gently theres a rattling noise (sounds like a ball bearing in a plastic cup)coming from under the tank. im thinking this is pinking but have never heard it before to confirm. anyway, ive tried better fuel(im presuming unleaded is fine)but that makes no difference. its an italian import so would anything such as carb jets be different enough to cause this. my clymer manual doesnt give details of jets/spark plug type for the ten, so does anyone have this to enable me to check. thanks for any help.

Sounds to me like the cam chain might be the problem. I don't know if the XT has an automatic chain tensionner...maybe it needs adjustment.

If the mileage is really that low, it is very unlikely that the chain itself is worn out, so I'd look into the the tensionner first.

Maybe the rubbers between the carbs and the cyl. head are leaking. This causes poor mixture and pinking.

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Fred, XTZ660, Holland.