Pair/Reed Valve block off...

[Draco1340]

It can be disconnected and reconnected in 10 seconds. You also need to disconnect it if you are accuratly tunning on a dyno or data logger. Completely legal and the norm for all IHRA classes. Its the only HP mod you're going to find that is for free.

 

[PetriK]

Get rid of the entire beast with a little help from Smithabusa
https://www.hayabusa.org/forum/gen-...r-valve-solenoid-removal-gen-ii-hayabusa.html


Or contact Jay over at APE for a very nice block off plate...
https://www.hayabusa.org/forum/ape-race-parts/112898-08-09-pair-valve-blockoff-plates.html

This has an idea !

I have been against connecting the crankcase to the pair hosing (and also free up some space inside airbox) - but as we can now program the pair to open at a certain RPM we could use PAIR for free venting when there is positive pressure from exhaust to crankcase and then close the PAIR valve when the vacuum from exhaust gradually builds up.

Anyone measured when the exhaust starts to generate vacuum from PAIR to support this approach ?

 

[Draco1340]

Petrik,
Because of the 1-way reed valve in the cover, the PAIR never sees positive exhaust pressure pulses, but it does see the negative pressure pulses. You can generate about 2 PSI vacuum even at idle. The only down side is that you loose almost that amount on your oil pressure. If you have bad oil pressure at idle, DONT connect the PAIR to crankcase.

 

[PetriK]

I recall us gaining more than 3hp with proper crancase vacuum pump, so this is interesting...

So we have two points here regarding crankcase ventilation
1) At low RPM allow free venting from crankcase to airbox
2) At high RPM connect crankcase ventilation to pair for maximum vacuum

I vaguely recall that the crankcase ventilation also has reed valves there, not sure though.

What I have in mind is something like the below, with pair possibly programmed for sligthly other RPM range. At idle and low rpm the pair valve is open allowing air to come from airbox. That way the crankcase pressure is not effected by the vacuum from exhaust. At higher RPM:s the pair closes and allows vacuum to be built by the pair system to free up some horsepower by applying vacuum to the crankcase.

 

[4acp]

a T Valve and 2 solenoids would do the trick for that system, activated and deactivated on a certain rpm value.

 

[PetriK]

I think its ok with already existing valve. Just need to open the valve if when the vacuum from exhaust is too big for the crancase.

This works only for non catalytic bikes, something like drawn above may ruin the catalyter pretty soon.

This is so much of a myth, the vacuum from pair to generating crancase vacuum for more power. Anyone really tried this ?

 

[OB_Boss]

The claim to more Hp was made by doing this back on the Gen I .................. personally have never checked the theory.

 

[PetriK]

Have not realized any gains from blocking the pair, but crankcase vacuum certainly gives a couple of ponies more on the racing bike.

 

[Draco1340]

I have measured repeatable 1 - 1.5 HP on dyno on ZX12. Take baseline measurement. Connect PAIR. Take measurement. Disconnect PAIR. Take measurement. Remember, it hurts your oil pressure because the pump isn't pumping into atmosphere; its pumping into vacuum.

 

[PetriK]

Yes, will be potentially loosing up to 14psi/1bar oil pressure. Recall that there would be an oil pressure valve which opens at around 60-70psi.

Just wondering that at what rpm that pressure will be normally reached ?

 

[flbusarider]

Hey Bike Dude, did you ever get any answer to the effect???? I was curious the same.
??????

 

[fallenarch]

I never got why the stock exhaust doesn't pop and removing the PAIR systems stops popping on bikes with slipons. Seems slipons would be well down the exaust stream from the effect of the PAIR O2 injection.

Sorry I got to this conversion so late and I'm way behind the curve. I also got my 09 dynoed and it only did 171 WHP. Could having the PAIR connected with Yoshi R77 slipons be partly to blame?

 

[TDI2Fan]

I just had my bike tuned (ECU Flash) with my Akra full system. We were unable to stop the popping while tuning. We were unable to get the PAIR off to make a difference on my bike. Tonight, I placed a rubber stopper "http://www.widgetco.com/00-rubber-stoppers-plugs" into the air box side of things. I can comment that my bike did have a fair amount of vacuum at idle on the PAIR line.

To verify the stopper was going to work, I plugged the line with my thumb and ALL popping stopped. Completed my mod to the air box and ALL popping is still gone.

I was not fond of the other suggestions on this thread about solutions for this.

 

[Wayneovich]

WOW just did this mod today and I definately feel a difference the throttle is crisper and it feels like it pulls harder at cruising speed best 99c I have spent yet

 

[busafastone]

I have the r77 yosh on my 09 and the pair valve block, the tech at yosh told me on the phone that this could cause to much crank case pressure!

 

[bradbusa]

I have the r77 yosh on my 09 and the pair valve block, the tech at yosh told me on the phone that this could cause to much crank case pressure!

why would blocking the pair valves create crank case pressure? the pair system delivers fresh air to the exhaust stream near the exhaust valves. as far as i know, has nothing to do with crankcase pressure or vacuum the way it was shipped from the factory.

 

[SWJ88]

marble worked like a charm, no more popping. I just took off my big cans and Im running it straight out of the cat until I get some coin for my spool. It dont sound bad at all though, everyone asks what system I have

 

[rroyter]

Did anyone see if the idle got rougher after doing the marble mod? I did it just now and while the afterfire has gone, it does seem to be jiggling ~100 RPM or so on idle.

 

[oneclassic70]

I installed aftermarket cans on my 06.. experienced the backfires and an erratic idle issue. As Well did an ECU flash to do the following:
1. Rev Limiter set to10,800rpm Soft Cut
2. Fuel Mapped to slip on exhaust.
3. ignition mapped for std timing corrections..91 oct
4. TRE Gear Based Timing Retard Elimination
5. Top speed limiter removed.
6. PAIR disabled.

Results: Bike runs like a banshee on roids.. BUT.. idle issue.. low idle at 800rps or less.. dies.. found adjustment screw and tried to adjust.. but doesnt find a happy medium.. its either jumpin up to 2500 rpms or dowm low again.. I did not do anything else to it. Any reccommends? Should I do the PAIR block off? Bike still has a little sputtering aka backfire but not to the extreme as before....

 

[Ryan]

bump....