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PAIR and EVAP delete advice please.


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Forgive me if this post is completely out of place. I am a new member and a new owner of a Magna 750 Deluxe that I've never ridden. I'm new to motorcycles in fact this is my very first, and the weather is beautiful so I'm anxious to get it rolling. I'm not too far off, but in removing the carbs in order to clean them, I discovered a ton of seemingly additional unnecessary complexity in both the EVAP system and the PAIR system. I removed several of the PAIR valves before I had second thoughts and figured maybe Id better slow down. Now, it's going to be hard to convince me that this system is necessary, however, if someone does so I will put it back. That being said, I doubt that's going to happen, so what do I need to do ultimately in order to make sure that I have done these removals correctly that is, left vents where vents should be, plugged what should be plugged, and basically configured the carbs and fuel system in the most prudent way possible. I'm anxious to get on the road of course, but I'm not anxious to break down so... I'm so happy to be here and I really appreciate any help I could get. Please do move this question to its appropriate location if I've embarrassed myself by putting it in the complete wrong place.

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Welcome! Did you do a search on here or the Googles? There's a lot of info about the PAIR system and removing it. I've removed it from a few bikes in the last year and it really made some space!

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No idea about your model of bike I'm afraid but I deleted the PAIR system on my current 01 VFR, my old 08 VFR and the 98 VFR prior to that and all ran much smoother at low revs without it.

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NOT necessary.


I've eliminated the EVAP and PAIR on multiple bikes.  Reduce clutter and weight.  Increase access and reliability.


The PAIR valves on my ST1100 were DONE.  The diaphragms were just goo.  Ran SO much better.



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4 hours ago, Presson said:

I'm thinking that playdeadbend0r was hoping for a step-by-step or a link to similar as opposed to words of success🙂




Remove EVERYTHING related EVAP or PAIR.  Every canister, valve body, hose, T fitting or vacuum valve.  There are vent hoses from the carbs in the rear that went to "something", the smaller one can now just vent to atmosphere, pointing down.  There might be a larger vent on your bike that might have gone to, or near, the air box.  Retain that, or point it down if it went to emissions. You can connect the bowl vents to each other, FR to FR, RR to RR, using all of your left over Vacuum rated hose.  There is usually one vacuum spigot on the carbs that needs to be properly capped.  Any vacuum lines that went to nipples on the head near the carb insulators, the nipples need to be capped or replace with a screw / sealing washer.


Here you can see the smaller vent line tucking under the large one pointing down, and the large hose going to a little breather box that just vents to atmosphere.




Anything that went to the air box, those fittings on the air box need to be plugged / capped (except the crankcase breather, seen in the above pic), usually any now unused ports are beneath the air filter.  If the engine heads had hard lines going to them from PAIR, they need to be cut off and sealed.  I even double rolled and crimped a friend's so he could take care of it later.  Never did.  No issues.  The fronts are easy, some bikes the rears require some fairly involved dis-assembly.




If you don't want to get totally into the rear, you can just use some of your tubing that was removed to connect the ends of the hard lines to each other after the PAIR valve has been deleted.




You can use the hard line fittings to make "block off plates"





Crack your second beer and enjoy the view...





You also end up with some clamps, tees, collars and doo-dads.





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