I recently had oil and all fluids changed on my RK 2002 for the first time since my purchase in 2010. After getting back from the garage I noticed a very faint whistle sound coming from what I believe is the front section of the engine (down by the filter?). Took it back to the garage and had it "fixed." Drove it back home and by the time I got it home I noticed the whistle again. Anyone else have experience with such a whistle? It's audible when the bike is running and not when I turn if off as stated in another thread.

 

I don't know about you, but I whistle when I'm happy. Maybe she likes the new oil!
Just kiddin, sorry I couldn't help myself...

 

Could be intake seal leak
Or exhaust gasketleak.
Not hard to tighten that.
Exhaust is easier so check first. About 9 lbs torque or less than spark plug. Firm, not hard, with a 1/2 hand wrench