The CB1100 Community Forum

OK, I can't take it any more. What is a pair valve?

(12-16-2013, 10:44 AM)Rboe_imp Wrote: [ -> ]OK, I can't take it any more. What is a pair valve?

see thread NEW BLACK PIPE , post #16.

Got it. Thanks.

So, is there any downside to plugging the PAIR valve? It obviously serves a function and by blocking it you disable that function. Sounds like this serves a similar purpose to the air injection on my old FI Triumph Bonneville. Folks would block off the air injection on those bikes as well when installing aftermarket exhaust. Left mine alone but did have a custom map from Arrow installed with the slip on mufflers my bike had. Bike ran flawlessly. I have a new Arrow slip on muffler on order for my CB1100. Interested to find out if the bike pops on decal.

(12-18-2013, 10:40 AM)SUPERCRUZ_imp Wrote: [ -> ]So, is there any downside to plugging the PAIR valve? It obviously serves a function and by blocking it you disable that function. Sounds like this serves a similar purpose to the air injection on my old FI Triumph Bonneville. Folks would block off the air injection on those bikes as well when installing aftermarket exhaust. Left mine alone but did have a custom map from Arrow installed with the slip on mufflers my bike had. Bike ran flawlessly. I have a new Arrow slip on muffler on order for my CB1100. Interested to find out if the bike pops on decal.

I believe popping is not pronounced when adding a slip-on but is obvious when removing the oem headers w/ have the cat convertor.

I believe popping is not pronounced when adding a slip-on but is obvious when removing the oem headers w/ have the cat convertor.
Pair valve plugging only stops extra air from getting sucked into spent exhaust to ignite unspent fuel. It's a simple post-ignition exhaust igniter.

I have read these bikes are setup pretty lean from the factory due to emissions. Wonder if blocking off the air injection enriches the air fuel charge to reduce the popping.

I created a thread in the How To section describing this mod with information from Honda about how the PAIR Valve operates and what function it serves.

[url=http://cb1100forum.com/forum/showthread.php?tid=1824]PAIR Valve How To

I just don't like the idea of shooting dirty, already-mostly-combusted, superheated air into my nice clean engine. Thanks for the write-up, on how to do this and why! I ended up blocking the PAIR at the forward-most hose under the tank, as it was a PITA to get my slightly-too-big but-smallest-I-could-get 5/16" rubber plug into the airbox. Then, once I had it in I worried it could pop out and get loose in the airbox. On Triumphs, the plug that comes with the air injection removal kits often farts out of the outer airbox. I remedied that for my dad's Thruxton with a better quality plug and some rubber cement, but on the CB I just couldn't get to the right spot inside the airbox with confidence.

What about taking something round that it slightly larger in diameter; like a coin and gluing/cementing it over the hole?

No dirty air is injected into your engine. Go read how the PAIR VALVE works.