hoser wrote:
Your going to need another piston kit, looking at the top of your piston around the outside edge with a lighted magnifying glass (thanks Afastcar) on the intake site where I thought at first the top of your piston might have contacted the head when the rod went lose was actually the aluminum of the piston starting to melt away you also can see where the carbon on the piston was starting to blister in that area.
The numbers on the piston are 871m08950
Heck these piston kits are cheaper than the 400 kits
https://www.google.com/search?q=871m089 ... =firefox-a" .".." .".." ."..
Also looking at the faces of the rings with the lighted magnifying glass the rings are trashed in a few spots they look pitted all the way around they have vertical abrasions, between the rings on the exhaust side the surface of the piston is worn smooth all the machine marks are gone.
I would never run this
Engine again with that ATVR head! Someone needs to stick a few of these CR500 heads up Neils ass maybe he could see the problem then.
Im assuming I will need to get a 90mm piston, no way to fit another 89.5 into that bore correct? I have always remembered that all pistons (even though same size) can vary in size and need to be measured up, then bore to THAT piston.
While its on the top of my head because I might forget later. Should the cylinder be bored .006 over as ATVR recommends or since its been Hoserized and were using a Pro Design head can we stay at say .004 or Wisecos recommended clearance.
I found this quote a Offroad.com
"What about the so-called cold seizure? Don’t let the name fool you … too much heat is still the cause. It happens because the bike is fired up and run too hard right off the bat. The cylinder can’t keep up with the rapidly expanding piston. In the case of water-cooled bikes, a cause of cold seizure is uneven heating of the cylinder barrel."
Remember I can quote Neil at ATVR saying to me .006 because of COLD SEIZURES....Does that mean hes boring to .006 for the dummies that don't warm up thier Engine before blazing down the trail, or is it because his head and cyolinder combination is CRAP and the cylinder barrel doesnt heat evenly. Good grief I just want a 500 Engine that I can maintain properly, warm up properly and be able to blaze the dunes without worrying about cold seizures and crap :(
I will leave the piston to cylinder clearances up to you.