As said try a diffrent oil... Motul 5100 or yamalube..
take the for a long ride get the motor hot & keep it hot
for a long time... could be somthing as simple as gummed
up oil rings...

A good hard ride every now and then can go a long way
to keeping the motor clean inside..



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__________________
Harley Davidson..
The easyest way to turn gasoline into noise with out the side efect of horse power...