One way breather valve differences

Gandpaul

does yours have to be bolted against a plate?

Hortons Norton said:

OK had to show this as I just found this listing on E-bay, http://cgi.ebay.com/ebaymotors/CRANKCAS ... 335bda1706

Click to expand...

From the description it's a PCV valve, if you're going to go that route might as well buy the $3 one from NAPA...

Both bikes are running the XS breather valves for some time now and really work nice, I just thought I would show something coming out of England. :roll:

I prefer the clean mounting directly to the back side of the timing case (refer all arguments as to timing case breathing to the "other" thread)

One could also bolt it up to a small metal plate with a brass hose nipple on it and not have to open the timing chest.

It's a fact that once the engine pumps through a couple of strokes, there is negative crankcase pressure and the diameter of the outlet is insignificant. In short, IT WORKS.

Just wondering how this equates with a wet sumped engine. As I understand it, the worry about starting a bike in the wet sump condition is the risk of blowing the oil seal, but if we have a negative pressure after a couple of revs, then were's the the worry?
Terry

A wet-sumped engine will still give you problems, espeically if you have the thin breather pipe plumbed to the airbox as fitted from the factory!

I don't believe the one-way reed, placed as shown on the back side of the timing chest and plumbed vertically then out back to an open vent, will dump oil from a wet sumped engine. None of mine have, but maybe that's becasue they don't have wet-sump issues...