Just put a new plug in then had to take it out to rotate the engine to measure valve clearance, which has got me wondering about the crush washers on spark plugs. Do you have to get a new crush washer to re-insert the same plug? What's the torque procedure for a plug in an ATV engine, snug plus a quarter turn?

 

No you don't have to get a new crush washer. Here's a general plug torque guide from Ngk on different size plugs,but best if you go by the owners manual.
https://www.ngksparkplugs.com/about-...g-installation

 

Right on, thanks for the info and the link.