Originally Posted by nigelcorn
I think most people will agree that at high speeds a lot of thumpers will burn some oil.
The issue is that many of the 2008's burn an excessive amount of oil, like a quart in 500 miles. Very few years before do that, and most of the post 2008's don't do that.
I guess my question to you would be why do YOU think the 2008's were so much worse than the years before and after?
I've read the '08 model year had a slightly changed ring design... don't remember the details (maybe someone could chime in with that), but seem to recall the ring type, thickness, hardness all were a factor. Am personally looking forward to 685 kit upgrade with the Thermo-Bob installed - slightly more power, less vibration and decreased oil consumption - all good. Haven't heard too many guys with aftermarket piston kits complaining about excessive oil consumption. I still maintain operating at higher rpms for extended periods places greater stress on pistons and rings - in my mind, it only stands to reason that the rings flex more and generally have a tougher time sealing. I've read this in car & bike mags, and heard this stated here too - it's on the internet - must be true!