I just added a bigbore kit and new crank (RB) and am having overheating problems. I found oil in the water after a desert race. Replace the WP seals and bearing and the Radiator cap. Found oil in the water. Inpected head and base gasket. No apparent problems. Going back to water pump. Ordered a new impellar and shaft. Someone sujested jetting. Not real good in this or any other area to be honest. Missed a race today because I can't figure it out. Not real happy! Any ideas or experiances in this area?