Truth about the Pair valve system !

[c10]

Its really meant to be dive equipment . You also do not save 2 plus pounds . Try 15.8 ounces , but I did not weigh the Scott Stites
block off plates . Guessing about 3 ounces so real saving 12.8 ounces saved . I also used a 4.7 K ohm resistor for no FI light . I have many 4.7K resistors from work . After reading about the ECU has the off option for pair system monitor I figured its like some of my systems at work just looking for resistance .

Here are some pictures / video

 

[c10]

Video . Dang the throttle bodies sound nice

 

[Don Hardcastle]

Video is set to private...

 

[c10]

Video is set to private...

Thank you .

https://youtu.be/dgBhc26pW94

 

[Bobby B]

Turkey Sub

 

[GIXERHP]

Mine is turned off in ECU reflash, and blocked off!

And the truth is the Pair valve is not needed except for
emissions!

 

[cyclefarm]

Thinking about doing this on mine. 12oz ain't much, but getting rid of all that plumbing would be a plus, bet it cleans up the engine compartment a lot.

"Dang the throttle bodies sound nice", this made me wonder if you think the mod lets you hear the throttles better? I'm all for that.

What wattage resistor did you use?

 

[c10]

1/4 watt . Gixerhp I plan on turning it off via ECU when it gets flashed , but for now to use block off plates that were a gift from a friend I just did the resistor .
Cyclefarm the pair equipment is not as cluttered as some I have seen on bikes .

 

[deon_hackstall]

I just did the pair 'sucker'mod. Used it to pull crankcase air out and into the exhaust.

 

[POWERHOUSE]

2-3 hp for no money is a good gain . . . just remember to pull the hose off the crank vent when you drop the oil . . .

 

[E Zurcher]

Pair sucker mod? Searched for it and couldn't find anything. Please explain. Is it for turbos only?

 

[POWERHOUSE]

Pair sucker mod? Searched for it and couldn't find anything. Please explain. Is it for turbos only?

Instead of pulling filtered air from the airbox, you connect that hose to the crankcase breather. This creates a negative pressure (vacuum) in the cases, enabling the pistons to move up and down more freely. This is an old drag racing trick, it is worth a few horse and is easy to do. And no, not usually done on turbos . . .

 

[BBMykey]

Wishing I had known about this prior to installing the block offs.

 

[no kanji]

Pair sucker mod? Searched for it and couldn't find anything. Please explain. Is it for turbos only?

If you search "pair valve for crankcase evacuation" there is a fair bit of info. Controversial topic tho some tuners say NFW others swear by it
Might want to raise the idle speed up to 11/1200 RPM with this mod.

 

[c10]

First this is a no no . If you pay close attention to head design there are 4 holes in the head that bleed exhaust gasses straight up to the PAIR system . What stops constant air ( hot ) from reaching the air box is the PAIR reed valves/PAIR motor . High speed gasses flow to path of least resistance and the 4 holes in the head are STRAIGHT above 1 exhaust valve for each cylinder . So instead of making the 90 degree turn/bend to flow out some is now flowing into your crank case .
If you dont believe me simply remove you block offs , and start your engine . You will hear popping , and feel exhaust going upwards .
Also you may look at a bare head to see the holes I have described .

FYI PAIR is recerculation of unburnt exhaust gasses pumped back to the airbox for a second burn to reduce emissions

 

[c10]

It hooked up to you STOCK air box has more pull/vacuum .

 

[POWERHOUSE]

Might want to raise the idle speed up to 11/1200 RPM with this mod.

Some believe this mod messes with the oil pressure and that you will see your oil light "flickering" at idle. That is why no kanji is recommending raising the idle slightly. I did this mod on my own personal '02 over eight years ago - the bike idles at 1100, I've never seen the oil light come on at idle, never a problem. I've put over 15,000 miles on this bike since the mod . . . and it still pulls 198 rwhp with stock pistons and mild drop-in cams . . .

 

[POWERHOUSE]

First this is a no no . If you pay close attention to head design there are 4 holes in the head that bleed exhaust gasses straight up to the PAIR system . What stops constant air ( hot ) from reaching the air box is the PAIR reed valves/PAIR motor . High speed gasses flow to path of least resistance and the 4 holes in the head are STRAIGHT above 1 exhaust valve for each cylinder . So instead of making the 90 degree turn/bend to flow out some is now flowing into your crank case .
If you dont believe me simply remove you block offs , and start your engine . You will hear popping , and feel exhaust going upwards .
Also you may look at a bare head to see the holes I have described .

FYI PAIR is recerculation of unburnt exhaust gasses pumped back to the airbox for a second burn to reduce emissions

Sorry C10, you are not correct. PAIR is NOT a the re-circulation of unburnt exhaust! The PAIR system takes clean, filtered air OUT of the airbox and through the reed valves into the exhaust. The reed valves prevent the exhaust from getting into the PAIR system - air will only flow ONE way - into the exhaust. If you take the PAIR tube off the airbox and start the bike, you will notice that there is suction at that tube. The whole idea of a "clean air" or PAIR system is to inject air into the exhaust, diluting the gases and making the bike pass emissions when it really should not. Many bikes have them, they all SUCK (literally), and because of the "diluting" effect, we have to block the PAIR system when we are on the dyno to get the correct AFR readings . . .

 

[c10]

After inspection of the reed valves I can see the large steel tab to prevent flow upwards ( towards airbox ) So I stand corrected by Frank . Thank you Frank .
I would like to know though why if you start the bike ( no reeds / block offs ) do you get a suction when it clearly blows up / outwards ?
Over on the ZRXOA ( exact same system on ZRX 1100's 1200's ) we install 4 alum plugs in the head so no block offs are required .
Some members have even had the 4 holes in the exhaust ports welded up while the head was off for porting / big bore work .

 

[deon_hackstall]

All i know is that it works. No more dirty air being pumped into my air box (you ever look at that piece of foam in the back of your airbox). I have several dragstrip trips and over 1000 miles on my bike since it was modded with no noticable issues. I did disable my O2 sensor because this mod makes the sensor read a false rich.