Light grey smoke

I'm still a little new around here but wondered if anyone could give me the low down on what could be causing light grey smoke from an air-cooled Honda GB250 single? It only seems to smoke after it's been running for 10-15 mins and then it smokes continuously, not big clouds of smoke, just a little but it's noticeable.


Would appreciate any advice!

sounds like its burning a tad bit of oil to me. There's not much that can make an air cooled engine smoke. what do your plugs look like?

Plug looks okay but I'm not really sure what I'm looking for. I've been told it might be piston rings or valves, I live in the city and don't have a garage so fixing stuff myself is a little tricky...