I just installed a used head assembly for my '96 600 F3. Long story short, I did this because there was a ticking/knocking noise coming from somewhere in the motor after (I think) starving it of oil. I found the head for $150 so I figured what the hell....for that price it may be easier and kind of a fun off-season project, to change out 3/4 of the engine instead of paying my local dealer a bamillion dollars to tell me I need a new engine. Well, I have the new head in to my amazement, the ticking is gone. However, after starting it I heard a brand new noise. Kinda like exhaust was escaping from somewhere. I could not figure out how until I noticed on the head that it has 4 ports (two on each side) under the main exhaust ports. I looked in the manual and they are for the Pulse Secondary Air Injection Control (PAIR) System. I believe it has something to do with California emmisions. I live in Maryland [8D]. My old head did not have these on there. Is it possible for me to just plug up these ports or seal them off somehow?

Thanks,

m.

 

I don`t know about whether pluging the holes would be ok, but i just thought i`d shed some light on what the system does. The pair system is designed to draw in fresh air into the exhaust at certain predetermined times during running to mix with the gases and turn the hydro carbons into carbon dioxide a less harmful emision.

If from what i`ve read thats all they do blocking these holes in your case shouldn`t effect the running of the engine.

Hope this helps,? ?

 

You will be fine just blocking the holes off. It's not just CA bikes that have the PAIR setup, my 929 and 1000rr both have the system. Does your old head not have the ports in the top of the cover at all? You could just swap the new cover for your old one.

 

Nah, my old head does not have the ports, however the ports are located on the front of the head below the main exhaust, not on the cover. I've attached a pic. Is it still safe to assume that I can block these off as well?

Thanks for all your help!!

 

I see, thats a diffrent setup than the 929/954/1000rr. You would be fine to block those off, I have used radiator bypass caps in the past, but they tend to split in a year or so. You could also fill the nipples with JB quickweld.

 

Yamaha R models are like this. They use JB weld to plug.

Cheers

 

I`ve noticed this system on my bike, it makes all sorts of popping noises on the over run and as you blip the throttle on the down shifts because of it. Is there any benefit to removing it? i mean its only about 1kg isn`t it, and doesn`t do much else.

 

It is 100% good to remove the PAIR system -- especially if you're running an aftermarket pipe or can. There are places that sell the block off plates or you can make your own.

 

Poifect!! This is exaclty what I wanted to hear. Gonna start fabricating some plates tomorrow to plug those things up!

Thanks,

m.