I have a 2002 GS500 with 7600km.  Meticulously maintained and garage stored during winter.   Even after 8 months of storage she will start up and run without hesitation or smoke.  When I was last week she puffed abit of blue smoke for about 5 seconds during my ride.   Would anyone know how this could happen ? 

somethin with the oil check the valve seals.

I'd guess worn valve seals. Poor sealing would mean it could seep oil down, and either 'puff' on startup or occasionally during a ride. Things usually will expand and fill the gap(s) after it warms up, hence the startup puff.

Now if it's more like a mini-smoke screen, it's time for some upper and lower work. Or.... you could just ride it till it gets uneconomical to ride because of the price of oil

Don't panic.
You want to keep it away from the mechanics
as much as possible.
Keep an eye on it and see if it happens again.
7,600 km is not much for a 2002.
If the valves were never set it might be time.
Don't know if the valves not being set might have
something to do with it.

your bike is sending smoke signals to natives

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