Re: Speed & insane vibrations
Another facor that contributes to extreme vibration is an improperly mounted engine. It MUST be securely mounted to the frame, no rubber in the engine mounts and the mount fasteners torqued tight. The mount saddles must also conform to the frame with little to no gaps.
Other areas to look at is the exhaust. Is it secured in such a way that it isn't hanging out there in the breeze and vibrating? It should be secured to the frame as well as to the engine.
Knobby tires don't help either. They can add their own rough ride.
There are pages of discussion about vibrations here to read if you just type in 'vibration' in the search feature.
Balancing, even a perfectly balanced cranshaft, will not eliminate the inherent pulsations that come from a single cylinder engine, especially a 2 stroke. It isn't vibration but what you feel is the result of the combustion, the shock of it, being transfered into the engine and ultimately the frame and then into you. You can't take that away unless you shut down the engine.
A good example of this is high quality, precision made 2 stroke, single cylinder model airplane engines. Even with a high dollar engine and balanced propellers you still need to cushion the delicate radio components against the 'vibration' from the engine.
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