Filthy PAIR valves

jfheath said:
Back to the original post - (I am just trying to understand …)

Ok - I am not bothered about the blackening inside the PAIR valves. It seems to be normal and I have cleaned them up, and they will remain operational.

I turned my attention to the PAIR solenoid controlled valve. This is underneath the rear of the fuel tank and my shop manual states that

  • '...air should not flow from A to B, only when the 12v battery is connected to the PAIR solenoid valve terminals'. (@John OoSTerhuis' copy above , and also my 2003 copy of the 1300 manual)
  • This statement seems to contradict what is implied in the common service manual (@TerryS above) which suggests that the air control valve reacts to cut off the supply of fresh air during deceleration.
  • It also contradicts what is in the VFR800 manual (@TerryS above) - The air control valve is open when the coil is not energised.

So I checked today - A to B is from the hose that is attached to the bottom of the air box, to the hose that leads to both PAIR reed valve casings on top of the camshaft cover.
With no power attached, this valve on my bike is open but at present, I cannot test by adding 12v to the solenoid. There are no terminals on the top of it to probe, and the connector is not yet revealing the secret of how to separate the two halves, and it is quite difficult to get to.

The reed valves have nothing to do with the control of fresh air - the route from the airbox to the exhaust port is always open - providing the PAIR Solenoid valve doesn't close it. The reed valves just prevent exhaust gasses being injected into the fresh air system.

It seems that the operation is much more 'intelligent' as the ECM uses the coolant temperature, the air intake temperature, the throttle position, the manifold pressure, and the engine cycle to make its decision to shut off the fresh air to the exhaust port.

All of which is just information. I just need to establish whether or not my Solenoid is working. I assume that it is in which case my ST1300 manual is wrong about only being open when 12v is applied. Which would agree with what John O said in his post #11.
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ya that manual is poorly worded through out .... I think I kept mine when I removed it and could test its function ...... The valve can be tested with 12v but you need to rig up a circuit indicator and ride the bike to see if the computor is sending a signal to the valve ( AKA data logging :D )
You are reading correctly thought that on this engine the computor decides the state of the air valve ...... It may change state on decel or not :p BUT without a complete fueling map or some data logging info we are just guessing :(
 
jfheath said:
Thanks for your post, I'm not bothered about delving that deep. The sensors are Ok otherwise a fault would have been thrown. I have to assume the ECM is doing what it should. I just want to be sure that the solenoid is operating the valve when 12v is put across it, Because at present it fails the test in the manual.

All of which is to look into a niggle that I have had about the exhaust sound, which I first noticed at 25k. It might be nothing at all and always there - perhaps due to the very different engine characteristics of the post 08 models Compared to my previous 06. I am just taking the opportunity of winter to check over a few things.
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OK so i have no idea where I put my ST air valve ? maybe gave it away ? but I did test a ZX12R valve, V-star valve, CBR600 valve and a honda V-twin ( might be an ACE ) all of them are open with no 12v and close with 12v

For testing you could temp block the hoses and test ride then note a change in your issue ? and then remove the hoses from the valve ( or by pass the valve ) and test again for a change .You should also blow air into the hoses to make sure the "air" passages are not blocked in the head.
 
I agree the Honda manual is not well worded but it does sort of say that the valve should not flow air only when energised with 12v. The valve diagram is identical to that in the VFR800 manual which is quite definite about 12v to close the valve. Which would support the point that disconnecting the solenoid will leave the PAIR permanently open.
 
jfheath said:
'...air should not flow from A to B, only when the 12v battery is connected to the PAIR solenoid valve terminals'. (@John OoSTerhuis's extract of the 1300 manual above , and also seen in my 2003 copy of the 1300 manual)
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Agreed that it is poorly written but I fully understand it to mean that the application of 12V to the solenoid prevents air flow from A to B. Lack of any power to the solenoid does allow air flow.

Given such being the case, this would be in line with these parts of the two following statements that you also posted.
jfheath said:
  • ...... the air control valve reacts to cut off the supply of fresh air during deceleration.
  • ...... The air control valve is open when the coil is not energised.
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MidLife said:
Got here trying to brush up on the PAIR. Good help, Thank you!

Info from @Whooshka , @TerryS , @RaYzerman and @thekaz made good sense.

If it didn't for you @John OoSTerhuis , maybe a look here might help? It leads to an answer to your question at 6:40.
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When I installed the Bazzaz AFR mapper in Bluestar,,, part of the project was that the pair came out,,, and O2 blockers went in. The O2 plug caps had resistors in them,, I think,,, that emulated the O2 sensors, to fool the ecm. Blocking off the pair valves,,, and removing the pair solenoid and plumbing smoothed out the idle and lower rpm acceleration curve. And that made it generally easier to create a better performing a/f map. Now I am wondering what I can do with that extra space, that the pair controls formerly occupied ?? Cheers,,, CAt'
 
Catmandu2 said:
When I installed the Bazzaz AFR mapper in Bluestar,,, part of the project was that the pair came out,,, and O2 blockers went in. The O2 plug caps had resistors in them,, I think,,, that emulated the O2 sensors, to fool the ecm. Blocking off the pair valves,,, and removing the pair solenoid and plumbing smoothed out the idle and lower rpm acceleration curve. And that made it generally easier to create a better performing a/f map. Now I am wondering what I can do with that extra space, that the pair controls formerly occupied ?? Cheers,,, CAt'
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Too bad Bazzaz forced you to remove the PAIR. Nobody will believe the power of your ST is if there is no pop-popping!
 
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MidLife said:
Too bad Bazzaz forced you to remove the Pair. Nobody will believe the power of your ST is if there is no pop-popping!
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Removing the pair, was just a recommended option, to allow for the best a/f tuning. The pair reed valves are still there, on each cylinder head cover,, they are just capped, and so non-functional. They were pretty grimy (actually,,, they still are), after 240k km's. The provided O2 caps,, prevent FI code errors,,, since the O2 sensors are removed, (or at least unplugged). I had a bit of popping (after-burn) when I first started with the supplied maps. But as I developed my own maps (must have done 10-12 in total), better maps cleared up that symptom. I must confess that I recently bought a set of carbon Two Bro's mufflers for use on Thunder-STruck. I couldn't resist the temptation to compare it to the Del's on Blue-STar. I do expect more lean-burn,,, but time will tell in the spring !! I have a plan to control that eventuality,, cheers,, CAt'
 
MidLife said:
Both gutted?
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why would anyone gut a performance muffler ?? Both sets have baffles installed. And while I appreciate a proper performance sound,,, I don't like loud pipes. Performance is the ultimate goal,, otherwise one should stick with the heavier and more restrictive stock pipes. best,,, CAt'
 
Catmandu2 said:
why would anyone gut a performance muffler ?? Both sets have baffles installed. And while I appreciate a proper performance sound,,, I don't like loud pipes. Performance is the ultimate goal,, otherwise one should stick with the heavier and more restrictive stock pipes. best,,, CAt'
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Was wondering about the cats....didn't know aftermarkets came without them...seems obvious now!
 
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