motionper wrote:help any ideas, turbo 45 degree v twin 4.375 bore-5 inch stroke 20 lbs boost methanol fuel 11.5 static compression. wipes crank pin out on the BOTTOM of the pin 300-400 feet out-have tried less boost goes a little farther out before seizing. why is the problem on the bottom of the pin????? all i can think of is the setup is beyond the mechanical limit of the roller lower end??
motionper wrote:you just went over my head what causes to much rod pull on overlap?????
Cedarmachine wrote:In the later HDs I see the cranks and bearings set up tighter and tighter from the factory. They won't even slide sis to side because they are so tight.
I would try getting the crank pin DLC coated and set up the clearance to a "plug fit" or literally zero clearance. It's nothing new to preload or run zero clearance on a roller bearing. Look at every carrier bearing on rear differentials.
I think having actual contact of do the sides of the roller itself will perpetuate it to roll rather than "slide" across the pin and race.
Cedarmachine wrote:With roller lifters, they say "pressure fed". I don't see them advertised as "pressurized". It just means that it's force-fed oil from a pressure scource instead of relying on splash....
I like the idea of needle contact on the host bore and the axle all the time regardless if they are caged or not.