Just getting back into dirt bikes after a decade long hiatus (wreck, marriage, kids, etc). The last thing I wanted was some project bike that would consume every weekend because I'd spend more time working on it than riding it. Sadly, that seems to be exactly what I bought. I recently picked up a '98 YZ400F for $1200. Was one hell of a bike... for about 2 hours. While on a family outing yesterday, we stopped for lunch and I suddenly couldn't get it started. It felt like I'd lost all compression. I could roll the motor over by hand. We broke out the tools and the trail fix ideas started being thrown everywhere, but none of them panned out. The decompression cable/lever was not stuck, nor was it improperly adjusted. The decompression pin actuated smoothly. At this point I'm thinking a cracked valve or head, lost head gasket, or even rings in the bottom end. I get it home last night and pull the valve cover off and figured I'd measure valve clearances before going any further. That's when I noticed the right exhaust lifter was about 1/8 inch below where it should have been. Pulled the exhaust cam to verify, and sure enough that lifter is stuck with the valve just barely in the open position. Looking closer I could see a small burr on the decompression pin where it would make contact with the lifter. I figured it had flared or mushroomed out the top of that lifter and it had mildly galled the bore it rides in, and had now become stuck. I don't think this is a terribly difficult problem to solve. I have already removed the burr from the decompression pin and polished the flat and curved edges to prevent future occurrences, but now my attention turns to removing the stuck lifter and assessing the damage done to the bore. I cannot for the life of me get that thing out. I was able to get it to pop up to full height position by heating the head from the outside (expanding the aluminum and allowing the valve spring to push it up), but with nothing to grab onto the only way I can think of to get it out is a stick magnet. The only one I had at the time wasn't nearly strong enough to get the job done. I have some very strong rare earth magnets at work (Neodymium I believe) but after noting that it was stuck bad enough that the valve spring couldn't move it, I'm not very convinced that one of these super strong magnets will get me any further. Anyone have any other thoughts? How can I get this thing out? Maybe cleaning the top of the lifter and using duct tape as an adhesive handle in conjunction with the stronger magnet (two types of coupling mechanisms basically)? I'm worried about doinking the head and earning myself a whole top end project (the wife will LOVE that, I'm sure).