PAIR Valve Discussion & Bypass 

Hey buddy I'm sure you have heard this from many people before, but you sound just like Robert Downey jr. Not just the tone of your voice, but the way you enunciate as well!!!! Great video and always fun to listen to a celebrity wrenching on his bike, hahaha!!! Ride safe brother!!!!

This is so interesting, Rod. Years ago, I was having some headwork done to a big block Chevy. These fellows did heads for GM for different projects. I remember seeing heads bagged and marked "Darrell Waltrip", a NASCAR driver at the time. When I went to pick up my heads, a GM engineer happened to be there and I was able to listen to their conversation for a bit. My big takeaway was this: The engineer explained that when GM and the other American manufacturers needed to "clean up" the emissions from their power plants, they were behind the curve. So, an easy solution was to install an air pump (smog pump) and inject air into the exhaust. This didn't really make the exhaust any cleaner, but increased the total exhaust volume. Thereby "reducing" the percentage of bad gases in the tailpipe. If I remember correctly, that conversation was 40 years ago. I have a '98 VFR, 49 state bike, no cat, no sensors. I can't see any reason to delete the pair valve. Agreed?

Thank you Great video

Thank you for showing the diagram. It's way easier seeing it than trying to imagine it.

Excellent explanation

Dude are you really Robert Downey Jr.? Your voice sounds EXACTLY LIKE HIS! HEY EVERYONE!! IRON MAN IS WORKING ON MOTORCYCLES!! AWESOME INFO ON THE VALVES! I DO APPRECIATE THE TUTORIAL! NOT TRYING TO BE DIS- RESPECTFUL..YOU GUYS DO GREAT VIDEOS!! A++! ITS JUST AN ADDED BONUS THAT IRONMAN IS NARRATING!! THANKS AGAIN FOR THE VIDEO!! KEEP UP THE GREAT WORK!!!

Thank you so much for the video and explaining the pair valve system. I have kawasaki 2016 z800 and recently i installed two brothers slip on exhaust. The exhaust system on z800 is designed in such a way that if i want to change slipon exhaust the exhaust collector box comes with it. Catalytic convertor and o2 sensor and oem headers remains in place. So i chnged the slipon but since then when i deaccelerate , i hear some decel pop sounds from exhaust. i dont know if this is something i need to worry about or if it would hurt the bike in anyway. Ps. I havent touched the pair valve yet.

This effected my ST1300 it dropped the idle from 1000 to around 900 I was afraid it would stall. It did change some popping to a very light puff kinda but not a popping. I thing instead of blocking it maybe reduce the air going through it.

I'm so glad I watched this. I'm about to put on a full exhaust and was wondering if I should block off the pair valve system because I heard keeping it can cause backfiring in the exhaust. I wasn't aware that it would make my bike appear to be running lean. If that is the case, would it make my bike start to run rich based off of false info?

Well with the pair valve on the exhaust and valve they run hotter without they run cooler so there is in part a reason to delete the pair valve

Great video. I have an 09 vfr800 with original exhaust and cat. When doing slow speed riding and using the clutch i get a really annoying vacuum popping sound from the pair valve. I removed the electrical plug from the valve and the popping stopped. The bike was also way smoother to ride. But is that maybe harmful to the cat and bike?

Hi I have a 98 vfr800 5th gen, no 02 sensors, no Cat, I want to disable the pair system on my bike, can't see the point of it being there, I have an aftermarket end can and it 'pops' when I shut off the throttle whilst riding, anyway wouldn't just unplugging the electrical feed to the pair solenoid do the trick and if not why? getting to the paoir valve on the 5th gen is much harder to access being at the front of the airbox, up behind the oil cooler, great vid, subbed.

I like the sound of the popping on deceleration, and as it does not effect performance, i will not be deleting my pair valve

I want to ask a question about how most bikes handle crank case ventilation. I have a 2008 gsx 1300 and can't find much on the subject. Some guys are saying the pair valve is part of the the crankcase ventilation as well on this bike.

Do you need to blank the check valves and reroute the front crankcase breather back to the Airbox?

But how can that cause a problem with the O2 sensor if the O2 sensors in front of the cat

I’d like to see or hear the difference in a side by side video

The pair valve is the exact same thing as an air pump on a car, when the engine is cold it needs more air in the exhaust for a complete burn if running a cat converter...until the cpu reaches closed loop, then it shuts off. I know very stupid, it really isn't needed on a motorcycle, neither is the cat.

If Ihave Power COMMANDER Ihave doe pair mod or is ok my question is because I buy block free plate already

I have a leak in the exhaust lines of 2 solenoid valves on my motorcycle. As a result, all eight exhaust valves are covered with white powder. May I ask for a solution to the problem?

My bike has a pair valve and no cat. So your wrong. Not every fuel injection system adds fuel when it's cold for warm up.