The bad: ATV was parked about a year and a half ago. The plastic clutch cover shroud had warped slightly and had been lightly rubbing for the belt pulley for years and finally rubbed a hole through. Last weekend I removed the cover with the intention of replacing after servicing. A good battery got it fired back up with very little effort, and it seemed to run fine. Shut it off after 10 or 15 seconds to roll it out of the shop (had the seat and side shrouds off, so did not want to ride). Outside the shop it fired right back up in neutral, and I watched it run for 30 – 40 seconds, playing with the throttle. There was no engine noise and the throttle response seemed great. Then there was a metal on metal “clunk” and the engine died. Now the engine will not turn over. There is a small amount of play when working the pull rope, the crank is not seized, but it is very little play. My best guess is the timing chain broke, but I'm far from an ATV mechanic.
The goodish: All the plastic is in great shape for its age. Tires are several years old but have almost no wear on them (90%+ tread). Brand new clutch cover shroud included. It had been in my family (uncle, then dad, then me) for 20+ years. I have all the maintenance records for that timeframe. Before it was parked due to the shroud issue, it seemed to still be running as strong as it was 20 years ago. I left the shrouds off for the pics so potential buyers could see everything (assuming a buyer would need to remove them to fix it anyhow). All shrouds and mounting hardware are still present and included.