Krank Vent Plus, anyone use one?

[musicman]

So I bought a product I thought was kinda nifty from Hayden Enterprises, called a "Krank Vent Plus" for my 550. Thought the logic behind the product was good, price was steep but I'll always spend money on something quality first if I can afford it. So that's what i did. Ran a new breather line to my now empty air filter box under the seat, put the valve there (installed correct direction), and ran the outlet into a bottle to act as a catch can.

Rode the bike for about 60-65 miles with the valve installed and it failed pretty quick, you can't blow air through anymore in either direction, plugged case vent meant all kinds of oil leaks.

Just curious if anyone else has tried one, and if you have, how is it holding up? You'd think for how expensive these things are that they'd be pretty stout...

[Dogma]

I think just about everyone who uses pod filters just attaches a small filter to the vent line and uses a catch can.

I've never heard of anyone trying to maintain "proper crankcase vacuum" on a GS, and I don't see what advantage there might be, other than pumping a tinier amount of air back and forth under the pistons.

How is this thing meant to maintain a vacuum without attaching to a vacuum source?

[musicman]

Has to do with the air displaced by the pistons when they come down, theory is let the air out and don't let any back in. Really big deal on something like a Hardly Dangerous, single pin crank means there's a lot of air that needs to exit the case from the 2 pistons coming down, let alone ring blow-by. In the cage world I'm a turbo nut and am really stubborn about good case ventilation, and not a filter on the valve cover. Other than a little electric air pump I thought I'd give this a shot.

And it was working for a little while at least, I know it's just a baby engine but I swore it ran better, smoother, and just a tad more responsive, even peppier. If it would've held up I'd leave it. Automotive PCV valves do the same thing actually (not many know). They don't really have a vacuum source, since most the openings are pre-throttle plate. But they do have a valve, and actually work off a similar principal. So it's not something cutting edge or rocket science. Having a vacuum on your case helps the rings seal for one, there's a hole mess of advantages to having a few inches pulled, horsepower gains, engine longevity, just to name a few.

[mrbill5491]

Interesting...wonder where my crank case vents if it even does and should I vent it?? Okay GS wizards let me hear some thoughts about this.

[JEEPRUSTY]

I thought the circuit atop the valve train regulated the crankcase pressure.
Meh!

[Roger P.]

I've often thought that crankcase ventilation on the GS1100 was marginal to poor at best.

[musicman]

Well the company is great to work with, really friendly. They say that the only thing that will make the valve fail like it did is gasoline. Seems to me that if you make something like this you'd use a rubber that was resistant to it, oh well. Anywho, they're going to rebuild it free of charge, sending it in tomorrow. Probably won't put it back on yet, want to run the hose through a separator first then to the valve. If it goes again then I'll have it fixed and sell it to some Harley guy, lol

[Steve]

Has to do with the air displaced by the pistons when they come down, theory is let the air out and don't let any back in.

The biggest problem with that theory is that, in our engines, when one piston comes down (it's actually two pistons), there is another one (two)that is going up to balance the volume of air inside the crankcase. Yep, the volume of air inside a GS engine remains rather constant.

.

[musicman]

And you're correct, but they're coming down for different purposes, so there's still some air to be displaced, be it blow-by or such. Minimal affects I guess on a 4 banger, but seemed worth a shot. Might be more fun to rig an electric vacuum pump up, probably would be more beneficial.

And I decided to search, lo and behold, I'm not the only guy here that did try one.

http://www.thegsresources.com/_forum/showthread.php?t=191296&highlight=krank+vent

Seems his failed too. Interesting...

[musicman]

What I should do is actually hook a gauge up like I did in my camaro and monitor the vacuum, if any. Would be interesting to see if it actually does anything at all, I'll do that as soon as the repaired unit comes back and post results.

[TheCafeKid]

Forgive me if this sounds ignorant but I'm not familiar with Harley design enough to know, but aren't most dry sump designs anyway? Meaning there's no oil kept in the cases?

[rapidray]

ALL of the Pro Stock cars & bikes use electric vacuum pumps to create a vacuum in the crankcases. This increases ring seal & makes more power. This also lets you use lower tension rings for even MORE power & still have good ring seal. It WORKS!!! On a GS motor it is good for 4-5 horsepower & WILL pull oil out of the motor if placed wrong or you have too much oil in the motor. Just so you know, P/S bikes only use 2 quarts of oil in them. Ray.

[mrbill5491]

Okay so where would one mount a case vent on a GS motor?

[Billy Ricks]

Most vent out the top of the valve cover. The vents talked about in this thread have failed for two members who have tried them. I doubt I'd spend the money for one. The vacuum pumps Ray is referring to are a different sort of animal. It's been talked about before when someone was trying to come up with a compact unit that would work.

[gearheadE30]

I bet you could find valve from an automotive vacuum brake booster to do the job...it's the same principle, and they last forever. The one on my BMW has lasted 250000 miles and can resist the 10 psi of boost and has no delay when left foot braking at the track, i.e. it responds quickly.