Ideas For Mounting Crankcase Breather

The brake check valve creates a vaccumm inside the engine, maybe not as strong as plumbing it into the exhaust, but a vaccumm.
On the two nipple breathers, some had one side plugged with a solid plug on one side and a plug with a small hole in the other. So plugging one side and hooking a brake check valve will work fine. Maybe get a one nipple breather and use that instead, it will bolt right on.
Leo
 
Reid said:
I have seen it in several forms over the years Mr. Gasket makes a kit for your drag car, uses the exhaust passing over a small tube going in to the header. Suzuki gsxr 600,750,1000 and hayabusa have passages drilled down into the top of the exhaust ports that pulls pressure from the crankcase via a hose
Click to expand...

Okay, I had heard of using vacuum pumps but I can see how a venture effect in the exhaust might do the same. I'm guessing that with a bit of experimentation it could be made to work anywhere between the head and almost to the end of the pipe.

As a matter of fact, a venture effect could be produced by placing a piece of open pipe facing into the wind and funneling air into it then installing your tube into the pipe as if it were an exhaust pipe. The drawback would be that the effect would be tied to the actual speed the bike is traveling and not engine speed so the effect would be less most of the time.
 
Has anyone just blocked this off? I believe they do something similar on sportbikes... Pair valve mod / block off plates or something like that...
 
Dumb question time: when you guys have installed the brake check valve, I know you said "The valve faces the motor" but does that mean air can flow INTO the motor or OUT OF the motor only? I'm assuming Into but I'm not 100% sure. Thanks.

D
 
davem222 said:
Dumb question time: when you guys have installed the brake check valve, I know you said "The valve faces the motor" but does that mean air can flow INTO the motor or OUT OF the motor only? I'm assuming Into but I'm not 100% sure. Thanks.

D
Click to expand...

You are correct, Sir! In doing that you create a slight vacuum which helps to seal the engine and improve performance in amounts so small we cannot measure them. But the best part is it helps to keep from drawing dust and trash into the engine.
 
When I replaced a cam seal recently I put one of mike's reed valve jobbies on as a little oil leak insurance. I used maybe 3 inches of the breather tube to run it staight back, bolted the included bracket to the battery box then routed another couple of inches of tube from the exhaust side of the valve to lay over a pod. I put a little filter on that end for looks.

The concept is to create lower than atmospheric pressure in the crankcase by venting the pressure pulse created by the down stroke of the pistons and using a one-way valve to prevent sucking air back in with the upstroke. Once the crankcase gasses are sufficiently pumped out ( a couple of cycles) the pistons don't spend any energy compressing them and there is no pressure gradient encouraging your oil to seek freedom.

Norton folks swear by them.

It is unlikely that the power difference is noticable.
 
Yes, this is an old Brit bike trick we've adapted for use on our 650s. With the check valve, air only flows OUT of the motor. The valve closes and doesn't allow air to flow in. For that reason, no filter is required on the valve exit side.
 
5twins said:
Yes, this is an old Brit bike trick we've adapted for use on our 650s. With the check valve, air only flows OUT of the motor. The valve closes and doesn't allow air to flow in. For that reason, no filter is required on the valve exit side.
Click to expand...

yep, the filter just catches the bit of oil mist expelled on start up and then sits there looking pretty
 

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