Hi guys, I recently had my 500 motor rebuilt. Installed the motor myself and have jetting issues. Removed the head to replace gasket with copper and there's a lot of carbon/heat on top of my piston after an hour or so of riding. The water pump seal and shaft were both shot and lost a lot of coolant. I think it may of been overheating or detonating but I'm not positive. It's a 87mm piston and I'm running with an air box with keihin carb pwk s66a2 ods. The jet sizes are 175/45. I'll upload pic on my computer when I get home of the top of piston. Any ideas, suggestions are much appreciated. Thanks.