Check the cap screws on the engine. It sounds like you have a loose one or two.

It's a good idea to also check and tighten the screws after the first and second tank of fuel, as they come loose with the heat initially.


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I balanced my Skybolt as per the recommended C.G.

I've found this to be nose heavy. The C.G. can stand to be moved back a bit from the recommended.

I'm running the same setup as you... but I installed the battery just behind the firewall... wrong move.