8/22/2013 7:55 AM
I have the unknown plastic Motor mite power brake check valve on my Triumph,
XS650 and SR500. The Triumph is on the longest but all are still functioning
after years of use. The SR is a big single, 540cc, and oil tight. This bike
actually holds vacuum after I shut it down so I'm not sure a simple breather
tube or installing an air bleed would be better.
Tom Grahm tomterrific7@sbcglobal.net
8/22/2013 9:05 AM
I have used the automotive powerbrake check valves on my British bikes for over 40 years. The first was one of my Vincent Black Shadows. I tested it with a vaccum/pressure meter in the line between the engine and the check valve. When starting the motor the meter was on the pressure side. After @10 seconds the vaccum settled at @ -2psi and stayed there.
John Mead john.mead@prodigy.net
I'd venture to say most who are running some type of reed valve breather have already tried the Motormite, with unsatisfactory results. I know I did. If the Motormite is so effective why did Jim Comstock go through all the time and expense to develop his reed valve?
1up3down said:I'd venture to say most who are running some type of reed valve breather have already tried the Motormite, with unsatisfactory results. I know I did. If the Motormite is so effective why did Jim Comstock go through all the time and expense to develop his reed valve?
Count me as at least one very satisfied Motormite valve in my breather line customer
in fact, I have had the same one in place now for going on three years for the $9 cost, still no leaks
cheap and effective, what's not to like?
JimC said:I'd venture to say most who are running some type of reed valve breather have already tried the Motormite, with unsatisfactory results. I know I did. If the Motormite is so effective why did Jim Comstock go through all the time and expense to develop his reed valve?
Are you running a primary belt drive?
hobot said:Hehe, at times this is a confusing list Jimmy. Re-read builder Mead comment of lowering case pressure 2 pis and holding. Now think about this a moment... ...
OK Stevie,
Put an absolute pressure sensor in the tach drive hole -no connecting hose to mess with the readings and connect it to a scope so you can see what is happening in the crankcase. Then put your breather valve on the timing chest and see what you get. Make sure and look in the 3 to 5,000 rpm range where a Norton motor spends most of it's life and vary the load. Any one way valve will create some depression at idle. The pressure pulses in the cases might surprise you. Jimmy