Re: Chain Tensioner Slippage Prevention
I hate to rain on your parade but your solution has been tried, over and over and the results seem to always be the same. Eventually, maybe down the road a ways, but eventually the rubber/gasket material/tape/whatever will loosen and allow the tensioner bracket to move. The only sure was to keep it in place is to either weld it or secure it with a screw/bolt through the chain stay. There is simply too much force applied to the bracket to rely on clamping action alone to hold it. The best option, if a tensioner is absolutely necessary on your frame, is to fabricate a bracket that either welds or is bolted/clamped to the chain stay and seat stay.
As for rubber mounting your engine...enough has been written here on that subject. In a word: Don't do it. You are not eliminating vibration but instead you're transfering it to the engine mounting fasteners and at some point they can and will fail. Mount the engine as solid to the bike frame as possible. Not gaps, no looseness, but SOLID. Forget resilient mounts. They don't work.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"