Piston Galling

[Charlies Harley]

I had my 88cu in bored to 95 with SE pistions, cams etc in the off season as you did, but the break-in procedure was not the same. I took it out on the highway and excelerated up to 60km per hr and back down on compression 10 or 12 times then drive it normally, no lugging or over reving it. I changed the oil and filter at about 700km and have almost 6000km on it with no problems. Sounds to me that your rings didnt seat, and need to take the glaze off the cylinders and new rings.

 

[Hoople]

For me, the "Y" in the road and which direction I would go in,, is the leak-down test. I know you said he performed it, but I would have to see what the results were with my own eyes. With a new build like this, I would expect NO greater than 5% (and that's alot) when tested at 80PSI after just a 100 mile break in. No short cuts. An honest straight up test and it has to be a low number.

 

[HDDon]

There is a distinct difference in glazing and galling. If the rings did not seat correctly and glazed the cylinder walls rehoning can remove the glaze and give the wall the crosshatch patteren needed to reseat the rings. If the walls of the cylinder was galled this may not be be something that can be taken care of by rehoning, as the walls may be gouged and need reboring. Did you change from chain drive cams to gear drive? When the engine was torn down were the cam tensioners completly worn out. If they were did your engine rebuilder make sure all the debris was removed from the oil passeges? You did not mention any type of electronic fueler, if something was not installed to change the A/F ratio you may be running very lean.

 

[Sicangu Akichita]

The bike had a power commander installed in 2005. I had noticed that the rear cylinder ran 100 to 200 degrees hotter than the front. I used a infra red themometer to check it. He did say he made an adjustment to the power commander because it was running lean. By 10%.