You may not have this issue but the crankcase vent tends to do a rather poor job of keeping the oil inside the motor. Yamaha tried MANY variations through the years, none were a true Silver bullet solution.
A reed valve CCV system seems like a very good idea on any 360 parallel twin. Running a slight vacuum in the crank has some advantages;
lower pumping looses it takes power to run what is basically an unused air compressor.
negative pressure should help reduce oil leaking from engine seals, gaskets etc.
Norton guyz have the same issues we do, maybe a even worse with a "dry" sump and remote oil tank. They have some reed valve type set ups offered by the vendors, at rather high price points. They did did some studies and found reed valves will hold a slight crankcase vacuum up to about 4-5000 RPM, after that effectiveness tapers off, prolly about the max speed of the reed valves being able to act as a one way seal. Below 5K RPM prolly covers about 98% of all engine operation for the typical rider.
So the ole skin flint wants to try this and was thinking on lower cost alternatives. Then @Mailman mentioned this one is available.
I gotta say this looks rather sweet, compact, easy, just pay n go. But that's no fun?
So a bit of searching on Fleabay
first look was a reed valve for a small 2 stroke.
was a bit big for this use, an intake reed valve housing tends to be constructed "backward" for our CCV use.
Then I found that many motorcycle use a pollution reduction system with reed valves in housings.
Found a couple set ups so cheap, they are on the way here.
This octopus from a gixxer to my door for $4! Worth it just for hoses and clamps? Obviously bike wreckers can't GIVE away these systems.
this from a GS500 might be a bit more plug n play.
These systems use a vacuum solenoid to open and close the air passage depending on intake vacuum which we shouldn't really need/want for a CCV so will look into removing that. There's another wrinkle on oil in the vented air stream, I haven't seen explored, I will look into that also.
That's where I'm at for now.
A reed valve CCV system seems like a very good idea on any 360 parallel twin. Running a slight vacuum in the crank has some advantages;
lower pumping looses it takes power to run what is basically an unused air compressor.
negative pressure should help reduce oil leaking from engine seals, gaskets etc.
Norton guyz have the same issues we do, maybe a even worse with a "dry" sump and remote oil tank. They have some reed valve type set ups offered by the vendors, at rather high price points. They did did some studies and found reed valves will hold a slight crankcase vacuum up to about 4-5000 RPM, after that effectiveness tapers off, prolly about the max speed of the reed valves being able to act as a one way seal. Below 5K RPM prolly covers about 98% of all engine operation for the typical rider.
So the ole skin flint wants to try this and was thinking on lower cost alternatives. Then @Mailman mentioned this one is available.
I gotta say this looks rather sweet, compact, easy, just pay n go. But that's no fun?
So a bit of searching on Fleabay
first look was a reed valve for a small 2 stroke.
was a bit big for this use, an intake reed valve housing tends to be constructed "backward" for our CCV use.
Then I found that many motorcycle use a pollution reduction system with reed valves in housings.
Found a couple set ups so cheap, they are on the way here.
This octopus from a gixxer to my door for $4! Worth it just for hoses and clamps? Obviously bike wreckers can't GIVE away these systems.
this from a GS500 might be a bit more plug n play.
These systems use a vacuum solenoid to open and close the air passage depending on intake vacuum which we shouldn't really need/want for a CCV so will look into removing that. There's another wrinkle on oil in the vented air stream, I haven't seen explored, I will look into that also.
That's where I'm at for now.
