PAIR system removal

Joeywhat

Joeywhat

Joined
Apr 5, 2018
Messages
95
Location
United States
Bike
2006 ST1300 - Black
Did I miss an article on removing the pair system? I thought I saw one but haven't been able to locate it.

Are there any walk through on getting this done? Also, can I just block off the hoses or do I need to remove everything? Mostly doing this to lessen the engine decel pops.
 
The PAIR system consists of the solenoid (which defaults to open) which allows air to be drawn from the airbox, and the reed valve chambers on the cylinder head covers. Disabling the system can be as simple as jamming a marble into the end of each hose where it fits onto the cylinder head cover and refittin that hose, or complete removal, in which case you can unplug the solenoid (won't throw any fault codes), plugging the outlet on the airbox, removing the reedvalve covers and replacing with machined blank covers (these need to retain the rubber seal and be gas tight) and tossing all of the hoses etc in the bin. I never did it on my ST but have done so on my VFR800Fi (no performance difference but got rid of excess hoses) VFR800F VTEC (which I think runs better without the PAIR, more even VTEC transition) and my VFR1200 (no performance change detectable). The PAIR's sole function is to introduce air into the exhaust manifold to assist in burning off hydrocarbons, so no performance gain (and probably higher emmissions).
 
TerryS said:
The PAIR system consists of the solenoid (which defaults to open) which allows air to be drawn from the airbox, and the reed valve chambers on the cylinder head covers. Disabling the system can be as simple as jamming a marble into the end of each hose where it fits onto the cylinder head cover and refittin that hose, or complete removal, in which case you can unplug the solenoid (won't throw any fault codes), plugging the outlet on the airbox, removing the reedvalve covers and replacing with machined blank covers (these need to retain the rubber seal and be gas tight) and tossing all of the hoses etc in the bin. I never did it on my ST but have done so on my VFR800Fi (no performance difference but got rid of excess hoses) VFR800F VTEC (which I think runs better without the PAIR, more even VTEC transition) and my VFR1200 (no performance change detectable). The PAIR's sole function is to introduce air into the exhaust manifold to assist in burning off hydrocarbons, so no performance gain (and probably higher emmissions).
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Perfect, that helps a bunch. I shouldn't have an issue getting the bike apart, but knowing the operation of the system better is a huge help.

Now I need to decide if I want to remove it entirely or just block it off and leave it in place...
 
Joeywhat said:
Perfect, that helps a bunch. I shouldn't have an issue getting the bike apart, but knowing the operation of the system better is a huge help.

Now I need to decide if I want to remove it entirely or just block it off and leave it in place...
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The marble trick is quick, cheap and reversible. Then you can decide whether to go any further.
 
If you remove the pair system the engine runs much worse in idle. If it struggles. You need to increase the idle screw.
I did this and it runs not better.
And you wil destroy the catalic converters. The holes will block after a while. Then it runs much worse and the heat from the engine will increase.
Do this only with aftermarket mufflers.
 
PanRider1300 said:
If you remove the pair system the engine runs much worse in idle. If it struggles. You need to increase the idle screw.
I did this and it runs not better.
And you wil destroy the catalic converters. The holes will block after a while. Then it runs much worse and the heat from the engine will increase.
Do this only with aftermarket mufflers.
Click to expand...
I do indeed have aftermarket mufflers, that's why there's pops.
 
PanRider1300 said:
If you remove the pair system the engine runs much worse in idle. If it struggles. You need to increase the idle screw.
I did this and it runs not better.
And you wil destroy the catalic converters. The holes will block after a while. Then it runs much worse and the heat from the engine will increase.
Do this only with aftermarket mufflers.
Click to expand...
Also, if those are the symptoms you had when modifying the system it sounds like you ended up with a vacuum leak.
 
No vacuüm leak. It is normal that the engine idle different with the pair valves closed.
If you synchronise the intake, you need to block the pair hose. Then you notice the same thing. It idle much worse.
 
PanRider1300 said:
No vacuüm leak. It is normal that the engine idle different with the pair valves closed.
If you synchronise the intake, you need to block the pair hose. Then you notice the same thing. It idle much worse.
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I removed the pair system and the engine ran EXACTLY as it did before removal. The only difference was less decel popping. When I put the factory pipes back on and reinstalled the PAIR system, the engine still ran exactly as designed.
 
Many YouTube certified mechanics do this….take a good running motorcycle, and replace the exhaust pipes, and probably throw a K&N filter in causing the bike to run leaner and hotter, because they didn’t do fuel management etc, and the bike starts protesting by popping.
So they end up trying to solve a problem that they created.
And as pointed out, no difference in performance etc.
 
Igofar said:
Many YouTube certified mechanics do this….take a good running motorcycle, and replace the exhaust pipes, and probably throw a K&N filter in causing the bike to run leaner and hotter, because they didn’t do fuel management etc, and the bike starts protesting by popping.
So they end up trying to solve a problem that they created.
And as pointed out, no difference in performance etc.
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Well, you can buy me an ST that's prepared as you wish, and I'll ride it and not change a single thing about it.

Until then, this is what I'm doing. Still waiting for any actual contributions to this thread. If it's not to your liking not opening it is free of charge.
 
Igofar said:
Many YouTube certified mechanics do this….take a good running motorcycle, and replace the exhaust pipes, and probably throw a K&N filter in causing the bike to run leaner and hotter, because they didn’t do fuel management etc, and the bike starts protesting by popping.
So they end up trying to solve a problem that they created.
And as pointed out, no difference in performance etc.
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And that's what you get when you don't vet your YT mechanics ;)

You are painting with a rather broad brush... it often depends on the bike. Removing PAIR or similar is something I've often done as having it on can lead to dyno reading inconsistencies. And in many YT-adjacent cases, the enduser will finally suck it up and get their ECU reflashed. This isn't any different than what we did as punk kids on a budget when we put on a race slip-on -- lean became leaner. Now we are old and (supposedly) know better. I suspect the OP has a reason for asking, just like I did when I asked the same thing as a ST newb, and one of the OG guys felt the need to stand on my d*ck, lol.
 
DesmoRonin said:
And that's what you get when you don't vet your YT mechanics ;)

You are painting with a rather broad brush... it often depends on the bike. Removing PAIR or similar is something I've often done as having it on can lead to dyno reading inconsistencies. And in many YT-adjacent cases, the enduser will finally suck it up and get their ECU reflashed. This isn't any different than what we did as punk kids on a budget when we put on a race slip-on -- lean became leaner. Now we are old and (supposedly) know better. I suspect the OP has a reason for asking, just like I did when I asked the same thing as a ST newb, and one of the OG guys felt the need to stand on my d*ck, lol.
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Its easier to just consider the source and get a chuckle from it. Not everyone understands how the PAIR system works.
 
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I did the pair removal because it made carb maintenance and syncing less complicated. I also eliminated the charcoal canister.
 
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jrp said:
I did the pair removal because it made carb maintenance and syncing less complicated. I also eliminated the charcoal canister.
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Thats the same main reason I have done it, it makes working on the bike much easier.
On some it had no effect, on the VFR the idle was smoother, and yes, popping is now gone with the aftermarket exhaust.
The overall effect of removing the PAIR on a bike, depends on what bike it is.
 
Larry Fine said:
If you want to become a hero, find a way to flash ST1300 ECUs.
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I'm neither smart nor patient enough. While not a fan, "back in the old days" we often used DynoJet/Bazzaz piggyback fuel tuners. Is there not one available for the ST1300? I imagine the demand for performance ST1300 fuel tuning is not high enough for someone to crack the ECU, assuming it's possible.

edit: There are times when I should shut my fingers up, and do some research before answering ;)

 
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