For anyone wondering I went to see Chuck yesterday and he seems to agree with Rodneya that the cylinder looks like it has had some sand or something run through it. The ports are not chamfered as much as Chuck usually does, so that probably didn't help anything. The bore and piston on that cylinder is totally destroyed...we measured around .006" clearance. The clearance of the other two are pretty close...so the clearance was probably set up correct by the machine shop. We did note that the finish hone was done with a very aggressive grit though. I'm sure the cylinders were clean when it went together but I never split the cases so there's a chance there was some grit still down there that got into the cylinder on startup. That's my best guess for now.
The last bore was already 1.5mm OS so i've ordered a set of 2.0 os pistons which is the biggest i've seen for a GT750. The plan is to bore that left cylinder and hope it cleans up at 2.0 os. Otherwise I may have to find another set of cylinders. I have also split the case and am going to do the crank and water pump while its open.
The last bore was already 1.5mm OS so i've ordered a set of 2.0 os pistons which is the biggest i've seen for a GT750. The plan is to bore that left cylinder and hope it cleans up at 2.0 os. Otherwise I may have to find another set of cylinders. I have also split the case and am going to do the crank and water pump while its open.