Originally Posted by
Pattojnr
well i do have a few opinions about this engine already. and maybe it was read wrong about the hole. im talking abobut the inner part of the crank, elongate the hole in the direction the fuel is coming in from. so this would effectively double the area to catch the fuel on the way through, but in no means to drill the hole bigger, that will weaken the pin.
this is by far the tightest engine i have ever run in. normally preheating and engine to 70-80 c works a treat. im having to get 100 + to prevent the piston from getting stuck on tdc. that is a huge stress on the rod and the pin. all care taken runnign in the engine, and keeping heat into it while it runs , all helps on the rod and pin issue. but i guess ill be seeing the results in a few weeks. adding the extra shim while running in will also help, and running it in with a higher oil content and 16% fuel will also help. i wouldnt be hitting the track with it in the first 2 tanks, its too tight, i have 4 tanks through it now , just my opinions thats all.
I have the VZ-R engine modified by Uriah M, and he has elongated the rear portion of the crank just like you are saying. The Next time I have the engine apart I will take a picture of it and show you. I wraped a towel around the cooling head to keep the engine temp up, but yes it is still very tight with the added shim and approx 1/2 gallon of fuel through it. I use a heat gun to warm up the engine everytime and to reduce stress on the Rod.