thanks for the info. I kind of think it's an oil problem involving the front cylinder oil line to the rocker box. However, I am going to recheck the timing as suggested. It just baffles me why it's only the front piston that breaks downand not both. How about the scuffing on the front and rear of the pistons and not the sides of them. Is this normal or could it be an indication of poor bearings?

 

My only answer to that is because of the flywheel rotation more oil surrounds the rear piston than the front. This is why we notch both pistons for piston to piston clearance on strokers rather than just the rear piston like S&S does to get more oil on the front one.

 

Hows the wrist pin clearance?? If the wrist pin is getting thght it will tear up the pistons on the thrust surfaces(front and rear of them) also make sure the oil hole in the rod end lines up with the busning and is open. Some times carbon will build up and hammer the top of the piston if you are running tight clearances.

 

The wrist pin clearance is within specs (actually maybe alittle more than spec). Here's one for everyone.. The rocker box oil line has a small disk whichs looks like it could be removeable inside the coupling area of the hose. These are after market hoses being used. The "disk" has a small hole in the middle of it to allow the oil to pass into the rocker box. Is there a special purpose for this "disk" or can a person remove it without causing any problems with the oil flow. Does this "disk" constrict the oil flow causing it to flow better or is it in place to act as a defense against large chunks of grit getting into the rocker box?