All 650's PAIR Valve Removal

[Ryan Preece]

I do confirm that my bike was behaving just like yours, after installing the block off plates, it was much much smoother.

You can block the hole on the airbox and that very same pipe to close everything.

Thanks Mr F! Does installing the blanking plates give a slightly better result? If they’re not 100% necessary then I’ll go on ahead and block up the two bits mentioned above instead. I guess with the reeds left in place, it doesn’t make any difference as there’s nowhere for anything to go, in or out of the exhaust system into the Pair system.

 

[MrFritz86]

Thanks Mr F! Does installing the blanking plates give a slightly better result? If they’re not 100% necessary then I’ll go on ahead and block up the two bits mentioned above instead. I guess with the reeds left in place, it doesn’t make any difference as there’s nowhere for anything to go, in or out of the exhaust system into the Pair system.

You're welcome

If the port and pipe are blocked properly, there will be no flow of air so the reeds won't move.

You should be fine.

 

[koofdome]

I want to recap before I tackle this project later this weekend.

2018 USA model CB650F

So I remove the entire PAIR valve system once I remove the airbox, keep the reed valves in since the newer version SmartMoto plates have recessed slots? Then, don't bother with a resistor because US models don't seem to throw the code? ANYTHING ELSE?

 

[Ryan Preece]

I think I’ll need to buy and install the plates possibly. I’ve just blocked up that hole and the hose, taken her out for a run, but no detectable improvement at the moment. The 2nd and 1st gear bib bib bibbiling is still there. Strange as I guess those reeds are there to ensure one-way airflow, so if you remove that airflow, then you’ve basically made the pair valve device non functional, even though the solenoid will open it up with a closed throttle. Back to the drawing board.

 

[MrFritz86]

I think I’ll need to buy and install the plates possibly. I’ve just blocked up that hole and the hose, taken her out for a run, but no detectable improvement at the moment. The 2nd and 1st gear bib bib bibbiling is still there. Strange as I guess those reeds are there to ensure one-way airflow, so if you remove that airflow, then you’ve basically made the pair valve device non functional, even though the solenoid will open it up with a closed throttle. Back to the drawing board.

just to be sure

is the green one you blocked right?

 

[Ryan Preece]

just to be sure

is the green one you blocked right?
View attachment 8193

Yep, the green one at the rear of the box, I’d read all the threads on here first for instructions. I had a cap which fitted over perfectly, then shoved the hose back on over the top of that. Red one is the crankcase breather IIRC. Surprised not to see at least some improvement.

 

[MrFritz86]

Yep, the green one at the rear of the box, I’d read all the threads on here first for instructions. I had a cap which fitted over perfectly, then shoved the hose back on over the top of that. Red one is the crankcase breather IIRC. Surprised not to see at least some improvement.

Ok, just checking
really odd, mine was different within the first few rides.

Maybe rolling in gear too much when coming to a stop? and too little clutch when starting? <= this is something that I had to get used to to improve riding experience

 

[Ryan Preece]

Ok, just checking
really odd, mine was different within the first few rides.

Maybe rolling in gear too much when coming to a stop? and too little clutch when starting? <= this is something that I had to get used to to improve riding experience

I tend to feather the clutch at all slow junction work and town riding, whether in first or second gear, to get a nice clean pull away with no jerkiness. I’ll have another look at my technique again tomorrow, it’s a good suggestion to reconsider this. Done nearly 500 miles on it now, but I cannot remember whether the two demonstrator bikes I tried were exactly the same as this, with the same issue. I possibly hadn’t noticed it at the dealer’s shop, as it was a new bike to me at the time.

 

[MrFritz86]

I tend to feather the clutch at all slow junction work and town riding, whether in first or second gear, to get a nice clean pull away with no jerkiness. I’ll have another look at my technique again tomorrow, it’s a good suggestion to reconsider this. Done nearly 500 miles on it now, but I cannot remember whether the two demonstrator bikes I tried were exactly the same as this, with the same issue. I possibly hadn’t noticed it at the dealer’s shop, as it was a new bike to me at the time.

See if it's gonna make any differences, if that's the case.
The clutch is a bit funky since it engage/disengage when the lever is far out, and with very little movement.

Maybe the demos were different, I bet that all the bikes are a bit different from each others.

 

[byob]

I read through this topic but I am still slightly confused.
Say if I wanted to test the difference with and without the PAIR valve, in case of my bike, will I get the same effect by just blocking the air hose on the airbox?

 

[myarza]

I think the consensus is that Pair Valve removal on a completely stock bike will yield no noticeable difference and is probably not worth the effort though minimal. I decided to do the mod only because I have a full exhaust, kn filter and PCV. Popping on decel was much improved (90% eliminated) thats pretty much the main difference I experienced. For sure no noticeable difference in performance, maybe a little smoother throttle response but thats debatable in my case.

 

[miweber929]

I read through this topic but I am still slightly confused.
Say if I wanted to test the difference with and without the PAIR valve, in case of my bike, will I get the same effect by just blocking the air hose on the airbox?

Yes, absolutely.

I think the consensus is that Pair Valve removal on a completely stock bike will yield no noticeable difference and is probably not worth the effort though minimal.

So normally I’d agree, there’s no noticeable difference, however several members have done the mod and indicated smoother response at small throttle openings and smoother idle. I’d hesitate removing it long term on a stock bike since it actually provides a function with the cat but if you plan to eventually put a pipe on it, I see no harm.

 

[baugustine]

So normally I’d agree, there’s no noticeable difference, however several members have done the mod and indicated smoother response at small throttle openings and smoother idle. I’d hesitate removing it long term on a stock bike since it actually provides a function with the cat but if you plan to eventually put a pipe on it, I see no harm.

I did the PAIR removal before the exhaust upgrade. Much smoother lower RPM response with it blanked off. Very noticeable, at least on the F motor.

 

[adammatheww]

This is probably a really dumb question but I’m asking anyway😂 If I just block off the pair intake hose coming from the air filter with a marble, then get a PCV fitted and dynod, then at a future date do the full pair valve removal with plates, will it mess with the map, I.e will I have to get it dynod again? I assume no because I’m effectively already blanking off the pair valve with the marble but just want to see if anyone thinks otherwise?

 

[Brammers]

You assume correctly.

 

[miweber929]

This is probably a really dumb question but I’m asking anyway😂 If I just block off the pair intake hose coming from the air filter with a marble, then get a PCV fitted and dynod, then at a future date do the full pair valve removal with plates, will it mess with the map, I.e will I have to get it dynod again? I assume no because I’m effectively already blanking off the pair valve with the marble but just want to see if anyone thinks otherwise?

@Brammers is correct.

 

[adammatheww]

You assume correctly.

Thank you as always @Brammers and @miweber929 👍😁

 

[inf4cti0n]

I did the PAIR valve removal...works great with my Akrapovic.

 

[Danil]

I did the removal of the valve at 1000km (with a resistor). After that, I have been driven around 4000km, and recently got a check-engine. Tomorrow I will be visiting Honda. Any ideas, can it be related somehow with the pair valve? (Check engine is constantly on, no blinking or anything).

 

[baugustine]

@Danil there are dozens of things that can turn on the MIL. Retrieval of the DTC(s) are the starting point.