Does anybody else think that it is a strange place to vent into the lower port on the air box. My airbox has water and dust/dirt in it and this could get into the CC right? I re-routed it through a filter to the back of the seat.

Should be safe there. Why does the CC need to be vented?

 

The vent hose goes to the clean side of the airbox (after the air filter)...
Hopefully you don't have dirt in there, otherwise it could also go into your carburetor and that would be even worse than in the CC vent. What you've done is probably even better though. (I'm assuming you plugged the hole left in the airbox with a cap?)

 

You need to let air in and out ofthe motor under the piston, i have installed the PCV valve in that vent line.... so to let air out but not in.... works good so far

 

KW-

That lower port is so low that I didn't think it was inside of the filter...I should have looked this weekend when I changed the filter. Good point though.

EMS-

I've heard that the PCV valve is a performance enhancing mod but I don't understand how..do you?

 

It creates a vacuum inside the crankcase and thus the piston is not pushing air in and out thus relieving the engine of that extra work. It is purported to provide faster, freer revs.

 

I have dunked my bike twice and filled the cc once, and tainted the oil the other time. With the second dunk, a minimal amount got in, but it was enough to break down the mobile one. Which in turn, caused the oil to vaporize/foam/break down, and I sucked 3/4 of the sight glass in to the modified air box port in 50 miles. When I took off the air filter, the black oil was everywhere and the spark plug was covered in ash. Therefore, I believe the 3/8 drilled air box is a bad idea, especially when your running 8-9k for hours on the highway(230miles on Sunday). The remote breather....+1

Now, I have added the PCV valve on top of the cc port and routed it to the top air box port via a TEE into the smog system. Yes, I still have the smog piping on( for the stock look), but the reed valve has been replaced with a aluminum plate.

 

OK the PCV valve may be worth a shot. While I have the bike apart I may cut it into the CC vent hose beneath the seat. Somewhere I read that it has to be vertical...is that correct or can it lay horizontal beneath the seat pan?

 

Vertical. The valve uses gravity to seal it's self. I bought one with a 90deg elbow on top. I fits with about 1/4" of clearance under the carb.

 

I have my remote breather/filter tucked up under the seat just near the airbox and right side panel, kinda fit right in a small space. You should buy a filter then kinda play around with it and see where you can easily mount it. I also bought about 3ft of small dia 5/8" heater hose for this. Theres not a whole lot of room to do all this plumbing.

 

I like the water protection that a PCV valve offers, but I'm concerned about the vacuum it creates. Do you think the oil seals on the crankshaft etc. will stand up to the higher pressure difference. Also, since the KLX revs way higher than a car, can the PCV valve respond quickly enough to be effective?