XBR500 dies when hot

[richardeblack]

That plug looks awful, so a new one should improve matters. But it does beg the question how did it get like that? Looks like oil fouling to me, implying valve guide / piston ring issues.

Thanks Ian
Basically I think it may be the original plug! It's certainly the one that was in the engine at 59,000 miles. I was always sure it would break off like others had if I tried to get it out so left it while the bike was still running which turned out to be 60,000 miles later. I'm pretty sure the bore will be well outside spec at nearly 120,000 miles and it does use a small amount of oil.

[richardeblack]

Got it running with a newish plug and it doesn't seem to be misfiring and stopping now.  It also starts really easily.  What a surprise.  I'll take it out for a run later so hopefully will make it to the show on it.