Hi!
I've had an XT660R for almost 2 years now. After last oil change, some oil got into my air filter housing. Since I have a 2-in-1 collector pipe running from under my air filter housing, some oil gets from between the air filter housing cover straight on my collector pipe so it means a lot of smoke when standing with engine running. I got a bit deeper into that problem.

Yamaha centre said, that it is normal, that this tube fills up from time to time and I just have to empty it. There even is a small reservoir for excess oil that it wouldnt leak into air filter housing. Well it is weird that it took 15000km for this to happen, i havent touched the tube yet so I still get some oil leak to my air filter. I hope I dont have excess pressure in my engine :P that would be a bigger problem.

Ok now to the point

- Is the tube sucking air FROM the airbox or TO the airbox?
- Can I disconnect the tube from the airbox and reroute it somewhere else, using maybe a cone-filter or a foam filter in the end of it.
- Can I put a one-way valve in the tube so the air would move only in one direction and the oil wouldnt move in another?

What else can I do to make things better? I am sometimes doing something like this, i dont want the modifications to affect my fun: