Yesterday I took the bike out to run a few errands. Bike ran fine and when home I checked the oil.
I normally keep the oil around halfway between the Min & Max lines.
This time I was rather shocked to find the level had dropped significantly.
After refilling to around my normal level, I made a bee line for the airbox.
Sure enough, the moment I took the cover off the box I could see that the yellow filter had turned brown. It was totally saturated through.
I ended up draining just over 200ml of oil from the airbox.
Today I took the bike out for a 15km mildly spirited ride. Again, the bike ran and sounded normal and once home I re-checked the airbox.
Drained 50ml out just from this one, short trip.
The oil breather/airbox system on the V7-II looks to be different to the earlier models.
(This might be a standard setup for all I know, so sorry for my ignorance)
I had to lift the tank to see what the setup was, this is what I found.
The tubes from the heads run up to the section of frame under the tank, entering the frame section about 2/3rds down.
Below where they enter the frame (towards the rear) there is a tube that is attached to the frame and runs back down to the sump, with what I’m assuming is a one-way valve installed just before the sump.
Up from where the ‘head tubes’ enter the frame (towards the front) another tube leaves the frame and enters the airbox.
There are no other tubes to/from the airbox.
All other tube attachment points on the airbox (that were used for the earlier models) are plugged.
Any oil that ends up in the airbox stays there.
So as far as I see it, for so much oil to end up in the airbox either the return line valve is not working or I have a problem with excessive pressure?
The clips for the valve look to be crimped on. Can they be re-used if I disconnect the valve to check it?
Is there something I’m missing that I can check?
Cheers
