There is vibration from 50 km/u to topspeed. Piston is 576 grams and the small end of the con.rod 154 grams.
(Measured with the con.rod in the flywheels).
Total weight 730 grams. Balance factor 60% (Ian's advice) is 438 minus conrod weight (154) is 284 grams.
This weight of 284 gr. must be attached to the small end of the con rod.
The wheel must remain stationary when placed in any position.