This is a 95 sl 650 -- I recently rebuilt the carbs and had it starting good and reliably. Took it out to the water and had bogging issues while idling. Turns out I had the wrong year carb I brought it back home and after adjusting the settings. Went to start it just because...well then I discovered the woodruff key was sheared. So i pulled the engine out just enough to get to the flywheel easily. I wanted to go through and clean some stuff up while I was in there. So I get that fixed and cleaned up and put it back in. After I get everything put back together I try and start it. It starts immediately but revs really high! I shut it off quickly. So I've read up on this, and I am pretty sure I have an air leak. I'm also pretty sure I know where it is. When removing the engine, the gasket on the exhausts manifold ripped in half. I tried piecing it back together but that didn't really work. I have not done a leak down test but I have not had this issue until now. And the only thing I removed was the exhaust. So I don't know where else there could be an air leak if I didn't take anything else off. I will probably do a leak down test just to be safe but I wanted to hear some other opinions while I am waiting to be able to work on I on track here or is there other issues that could cause this "death rev"?