I agree with sounding like the 2008 epidemic. Venting and foam helps but that's not the root cause. Heat is getting generated in excess. Something is twisting. Had same issue with 2098. Run different motor mounts and had to shim secondary (the tower brace was the best solution). Could only tell once it was on a stand and opened it up you could see the belt twist. It doesn't sound as bad as what I seen in those but it's more than just venting. And the power thing is bogus. Run 280 hp on Yamaha belts and clutches and no hot temps. Put it on a stand and look I bet it will show something.