Motorcycle Repair: yamaha radian smoky, valve stem oil seals, yamaha radian

Question
i have a yx600 yamaha radian. it has been in a shed for a few years now. i originally stopped driving it because it was a little smokey, so i put a chemical in to clear out the smoke, but that made the problem drastically worse. it then burned loads of oil and oiled up the plugs seriously. now i have time to look at it and i was just wondering do you think it needs piston rings, or maybe just valve stem oil seals. i know a little about mechanics, but am far from being an expert, any help would be appreciated. thanks

Answer
If the smoke is particularly bad on startup it is probably the valve stem seals.

You can do a compression check on a warm engine to determine the condition of the rings. You should do a valve clearance adjustment first.

The only solution to bad valve seals is to replace them. Most of the time this requires removing the head but some shops may be able to do this without removing it.

Check the condition of your sparkplugs to find out which cylinder(s) are affected.