Hi folks!

Please share how you've solved the matter of crank case venting on your V4 race bikes! I've seen examples of twin venting where also the front cam cover is vented. Do you use a catch can of some sort, and where does the oil return to the engine? Where does the excess air get out?

I want pics, ideas, and facts on what works and what doesn't.

Cheers and thanks! Lasse

umm they are vacue to airbox design with oil retirn to cam drain as standard.
although i thought better was constant vacume.....

Here's a bad pic of mine.



It's some pvc polypipe with poly ends, a barbed hose fitting has been attached so oil can enter. The exit pipe is up high enough so that no oil will actually come out in normal circumstances.

I've seen some that return the oil to the engine (through the dipstick thread), I don't mind losing a little oil maybe you would in endurance racing.

cam is that a copy of the HRC tank or is the real deal ?

Mine just vents into the casting on the frame, never had any oil come out, ever.

Thanks for your input! Anyone seen this system? Seems both front and rear cam covers are hooked up. RLR mod?

/Lasse

royster81 wrote:cam is that a copy of the HRC tank or is the real deal ?

No mate it's just a bit of plumbing pipe with some ends screwed on!

Like Aly's mine has never collected any oil.

no one using crankcase presure stabillisation ? , not sure of the pro's n cons but could helpwith conpression stabilisation maybe....will have to do someresearch on this

Something like this?





Theres another pipe to the bottle for the CCV

That looks more like some kind of airbox/fuel tank pressure equalizer system, as used on 2-stoke GP bikes using pressurized airbox and carb. The system is used to avoid fuel starvation when the carb float bowl gets pressurized from the ram-air.

Crank venting is there as a means to avoid blowing out the engine gaskets, and to reduce engine pumping losses.

/L