I have an 82 XL500R with 17K miles. I had just completed a 200 mile, steady 65mph ride to the ocean, when something in the engine broke. I tore it down last night to find a disintegrated exhaust valve seat. Are these replaceable?

I kinda wanted to "bump" this thread back up to the top....... I have an XR500 engine that needs a top end rebuild, and was kinda wondering if there are any valve seats available for these old motors?????

I think that a competent machine shop just makes them. The problem is finding a good one. I had a bad experience with my local shop. It didn't get fixed right. I had XR's Only fix it and it's been good for years. I recommend them for engine machine work, just don't buy any aftermarket stuff from them. I'm pretty sure that they can fix the valve seats on the older non-RFVC XR500 engines. Give them a call at 760-244-2626 and ask.

http://www.enginedynamics.com/
Excellent work. If they can't fix it, throw it in the trash.