Bearings? It only has about 50 flights on it. One thing I did do today was opened a new bottle of wildcat 10% 2+4 and dumped the remaining 5 ozs. of cool power 10% from the old bottle into the new bottle of wildcat. I don't think mixing the 2 is causing the problem though. I know, I know.....old fuel could have had moisture in it....Nope, I just opened the cool power 3 days ago and had the 5 ozs. left that I dumped into the NEW wildcat fuel. I should have just tried a new plug while I out there today!