I recently came across a gent selling a titled 99 dr350SE frame. We got to talking, and I found out that he had engine trouble on the freeway and decided to part the bike out and buy a dr650 instead. So I bought everything he had for $500 as soon as I could get there. Two parts boxes, an engine and a frame, I knew I was in for a treat. Missing the front end, rear wheel, carb and instrument cluster. But I had a 99 front end already and was planning to use a trail tech setup anyways. Apparently this is the only picture I got. It was late, and I put the frame and engine on a cargo holder mounted on my front hitch. So I sold my 98 dr385SE to fund the new build, and so it began: The DRMXRLSEXZ 441? It's a DR frame and engine, RMX front end, XRL tank, Street Edition. X model year. rmZ plastics. Yeah, I know. Still working on it. I've had a few of these bikes in the past. A 90 dirt model, 97 SE, 98 SE, and 99 dirt model. Consequently, I have a collection of spares hanging around and a decent body of experience wrenching on this model. You can see my posts over on the dr350 forum where I spend way too much time. Back to the project: Bike was said to be running, but noisy, when disassembled. Good starting point. First thing I did was drain the oil. Then off came the clutch cover to check for a loose or missing shift drum bolt. All clear, it's nice and tight. I'll probably remove and loctite it anyways. Next I took off the valve cover. Sweet! Journals and cam look good. No oil starving. The more I look, the better things look. This bike may have never left pavement! Thought about just putting it together and assuming user error, but I wanted to do a 441 big bore anyways. So off came the head and voila! Things got hot! Definitely think I found a problem.. Piston was deforming, melting even. A piece of ring snapped off and played ping pong in the cylinder. Was embedded in the squish area still, and matched the shape of the indentations in the piston and cylinder. This is great! I was planning on resleeving and a new big piston anyways, so it's all good news to me! Speaking of new piston, here it is! Update 9/5/17: While I'm at it with pictures of new shiny things.. Update: Just about finished!