PAIR System removal - SV650 & 1000 '03 on.
 

PAIR System Explained K3 SV650 and SV1000


Here is a short description of what I believe to be correct but if I get something wrong I'm sure a more knowledgeable member will put me straight.

The PAIR system is for pollution control. It consists of a solenoid valve which can allow air to be directed from the air box into the exhaust path. When the ECU (bike's computer brain) thinks there may be a good chance that some unburned fuel is being released into the exhaust pipe the valve opens and lets some air into there too. The ECU will use input form various sensors (engine rpm, throttle position, O2 sensor if present, etc) to decide when this might be happening. The hope is that the oxygen in this air will react with the unburned gas to form carbon dioxide and water thereby preventing the release of unburned hydrocarbons, hence reducing pollution.

One of the side effects of this system is that when you replace the restrictive stock exhaust and put on a free flowing aftermarket pipe you will hear backfiring as the air pulse from the pair system hits the unburned fuel in the pipe and detonates it. This will primarily occur when you roll off the throttle. Of course since this detonation is not occurring in the cylinder it does nothing for your bike performance except give it cleaner emissions.

If the backfiring sound bothers you, you can defeat the PAIR system and stop it form occurring. There are a couple different approaches here depending on what exactly you would like to accomplish. If you decide to defeat the system you may want to go the full nine yards and remove all the associated hardware like the solenoid valves and tubing, etc. This will allow you to shave off about 4 pounds of weight. Its a little complicated to do this and you will need to get metal plates that can be mounted to the cylinders to plug the holes formed when removing the various bits. Also some monkeying around with wiring is required so no warning lights come on and everything works properly. However this isn`t to hard to do and other members have done it. You can find out how with careful searches

http://www.sv1000.inuk.com/ click on FAQs


Some have done what is referred to as the poor man's PAIR Mod. Simply plugged the hole that the PAIR system gets its air from and that made the backfiring go away. Now you have 4 pounds of useless hardware stuck to your engine. The ECU still tells the valves when to open and close and they still open and close when told to. But nothing passes through the valves because you screwed a 3/8 in bolt into the air intake Others have plugged the hose that is connected to this intake with a ball bearing essentially accomplishing the same thing. It would be nice to get rid of the 4 pounds but if you want to be able to easily return the system to stock for service, or inspections etc.

Interesting, but does the Sv650 00 have one of these - I can't be arsed with taking it apart .... again.

FI only

Incidentally after reading that page I don't think the solonoid is ECU controlled. It'll be wired directly into the engine timing so when exhaust port is open it lets air in (cause adding air when no residue fuel would make no difference).

Thanks. Now wondering how to reduce popping on K2..

The new FI models have 32 bit processers how and why would you wire directly into the engine timing ?

This has been fully recerched and does work when removed. The TL1000R owners have been doing this for years

Why would you want the popping sound to go away, I like it.

Mr. Plod doesn't. I've only the one rene at the moment - god knows how loud it'll be when I get the other fitted. 8)

Why isnt there a post in the HOW TO section on

How to remove the PAIR system or disable it ?

I've got twin Arrow's on mine and the PAIR is not disabled and I only get a pop or bang on the over-run :D :D

I suggest leaving it intact - it causes no harm