Pair Valve Blockoff Mod

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Help locating PAIR valve '04 VFR800

I want to do the pair blockoff mod on my '04 VFR. I'm unsure what the PAIR valve is. There are two hoses coming out of my airbox. One comes out of the right side of the airbox and goes to the rear valve cover. I'm guessing this is a crankcase breather. The other hose comes out of the left side of the airbox and goes to an assembly mounted to the airbox. There are two hoses coming out of this assembly that runs along the left and right side of the airbox and go ???. Which hose(s) do I block off?

Thanks for any help,
Joe

 

Jason,

Thanks for the link. I had read through it before but it didn't go into much detail. I re-read the WIKI post and it made more sense. I used a rubber stopper to plug the fitting in the left side of the airbox and reconnected the hose. I noticed that the idle dropped a bit and that it seems to drop RPMs quicker when the throttle is shut off. I don't hear any popping I usually have (Two Brothers carbon slip-on). I'll report back a bit later after I get the oil changed and take it for a spin.

Thanks again,
Joe

 

I took the bike for a short ride and there is definitely a noticeable difference in low RPM fueling. It is much smoother out of slow corners and easier to casually pull away from stops. I still get a bit of popping on decel but I suspect that will remain until I get a Power Commander.

Thanks for the help,
Joe

 

Pair valve question

Will blocking off the PAIR valve cause any damage to the Catalytic converter?

 

In theory, if I understand the PAIR valve correctly, it could accelerate the wear to the convertor because you will have a richer mixture traveling through the exhust more often. I don't think we've heared of any rampant cat failures due to doing the PAIR mod though. Just did it to mine with the PC3, I am un worried about trashing the cat, it won't cause any FI lights to come on nor should it cause any problems unless it actually becomes clogged.

 

Thanks, I'm just trying to get rid of the annoying surging on my 2008 around 3500rpm in the lower gears 1st, 2nd or 3rd. After reading through the post here on VRFWorld it looked as if the PAIR valve block off would help with that particular issue.

 

+1 to Tink's comment. I also hated the off-idle surge. PCIII and a custom map cured it all, as well as the power drop from 5500-6500 rpm. Maybe not huge HP gains, but a much better running machine nonetheless. You've already got the expensive exhaust, might as well go the last mile and maximize your rides performance with a PCIII and a dyno. You could still do the whole mod before you got a map, but the only real benefit is about an 8lb drop in weight.

 

again tink, no HP gains but the low rpm throttle response is better.

FI runs off of the 02 sensors so the AIR from the pair valves will affect the FI
maybe time to step up to a 6th gen to try before and after for this mod.

 

Thanks everyone...this is a great site. Judging from your replies I'm moving ahead with the PAIR valve removal, a PC and dyno tune. Thanks again.

BTW Tink, I found this bike on Craigslist in Aurora, CO. The seller was moving to D.C. and had to part with it. 447 miles on the ODO, BMC filter, Heli Bars, Leo Vince (alum), Zero Gravity double Bubble for $6500. Felt like a steal. I doubled the original mileage just riding her back to St. Louis.

 

yes they did, It is set up to lean the bike for emissions and it does affect the fuel mapping a tad.
PC is the way to go if you have the cash for it plus the dyno tune..
IMO there are other cheaper ways to get the same gains..

Also show me a Honda engineer riding a 6th gen and I will show you a honda engineer with pair block off plates on it.

 

:doh: :doh: :doh: :doh: :doh:

 

^^^^^^^^^^^^^^^^^^^

:dance:

Hi Five

Coming soon- a new thread asking about PAIR Valve mods, coming to a forum near you.

:hangme:

Its like the Rocky Movies.