Originally Posted by SportsGuy
Are you basically saying that stock, from the factory, the XR650 will burn it's piston unless modded?
I'm sure one off situations *can* happen, but I'm guessing there are thousands of happy XR650 owners running stock bikes without issues...
I'm sure with the XR650 it was'nt much of a problem, but with the XR650L stock tune definately is a problem that could result in such a situation and is very likely the cause of that particular failure at that mileage.
I know at least my bike at near sea level ran super hot to the point it developed a knock in traffic, my guess is pre-detination caused by a really hot piston and ultra lean mix, not to mention the tendency to burp and die coming off idle, basically in stock tune it was un-rideable by my standards.
Since jetting it and removing the smog parts all of those problems have gone away and it will definately live much longer, the spark plugs get dirtier but at least I know my engine will not try to supplement the lack of fuel being delivered by burning its own piston.