...since I have no other references and never had ridden one before, is the knocking sound and vibration at very very low reps normal? I assume so since it's a big one cylinder with auto clutch, just asking.
Sounds like the typical bucking syndrome that the 500 is known for.
Either put in a complete of lighter set of rollers OR do what I did. Remove 4 of the black stock 25gram rollers and sub in 4 light blue 21gram stock Piaggio rollers from a older 500. Be sure to keep a staggered pattered in the proper orientation (21-25-21-25-21-25-21-2) to keep things balanced.
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