Re: rear engine bolts
Welcome to the forum. I would keep away from mounting the engine in rubber. Sounds like you're already having vibration issues and the rubber mounting idea will only make it worse. You need to check to see that you have good, (total) contact area in the motor mounts. If the motor doesn't fit the frame tubes snuggly then you are asking for trouble in the way of broken studs or bolts and vibration. The motor must fit the frame and should fit without movement in any direction. Try replacing the motor mounting bolts with grade '8' Allen head capscrews available at Ace hardware. The front will be 6mm X 20mm, the rear bolts 6mm X 55mm. Those lengths are good for a standard bicycle frame. If you have larger seat and down tubes then you'll need to adjust the lengths. Don't overtighten the bolts. Torque them down until the lockwashers are flattened then give them a small amout more. Use new lockwashers. Keep us informed and post the results in the forum under the appropriate heading. 'Trouble Shooting"
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