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Before doing this mod, it must be remembered that there is another mod that uses the PAIR valve as a crankcase evacuator. reported to give upto 4RWBHP. Also, to see if this mod is for you, try blocking the hose that comes from the airbox (a bolt that can be screwed into the airbox spigot is a good start)

 

REMOVING THE PAIR VALVE 

TOOLS NEEDED IN ADDITION TO BIKE TOOLKIT 
6mm x 0.8 tap and associated bits and a knowledge of how these are used correctly 
grease 
compressed air gun 
10 & 12 mm socket on LONG extension bar/s (10mm for radiator mounts, 12 for exhaust middle mount) 
Ethylene Glycol antifreeze (1.5L) 
Distilled water (1.5 L) 
4 of M6x10 socket button head screws 
4 of copper washers to fit M6 screws 
block offs for the air box connection to PAIR and from vacuum connection from #4 Throttle body 
Loctite 
some spare oil to top up with (you will loose some) 
abundance of clean rags 

THE PROBLEM 

the PAIR VALVE ....pairvalve.jpg (134113 bytes)..(thanks Betablocker for the piccy)... takes air forced in through the air box, and injects it into the exhaust port in the head. this is for emissions, allowing more exhaust nasties to be burnt further down the pipe as it passes through the CAT (as we know Oxygen is needed for combustion) 

with the fitting of aftermarket exhausts, the PAIR has been known to induce backfiring, 
in the event of a front wheel "ding" I am reliable informed that the PAIR causes a hole to be put in the crankcase....avoidable if it was not there. 
it robs air from the air box that could be used for RAM AIR 
it looks unsightly!! all those "hydra tentacles".. 


GETTING TO THE PROBLEM 

remove both lower plastic fairings. 
remove connections to oil cooler (the ones ON the oil cooler) and radiator, not forgetting fan wire and thermostat connection on RH Side of radiator. 
remove the 4 mounting bolts, the radiator, oil cooler and front cowl comes out as one piece...have front wheel turned fully left lock, and bring the radiator out the RH side, rotating it forward around the wheel as you pull it out.. 

REMOVING EXHAUST SYSTEM 

remove exhaust system...don't forget the middle bolt.. 
(the bolts in the head holding the header in will be chuffing tight and pretty rusty...good idea to scrape the shit out of the socket before trying to put Allen key in...and then tap the Allen key in. Don't want the head rounding out...... 
remove exhaust , rest on floor directly under bike, kneeling on RH Side tilt the header AWAY from you, and pull bottom towards you, and you can manipulate the LHS oil cooler bent metal pipe connection out from in between header 1&2. 
Remove and sit on one side.. 

REMOVING PAIR VALVE 

undo the PAIR connection to the exhaust ports, when pulling off be aware there is a gasket underneath that will break when you take it off...just make sure you remove all gasket traces from the head..... 
refit nuts onto the studs and tighten down. 

undo the 2 top bolts holding the PAIR to the block (just under one of the main oil gallery castings) then on RH Side of bike there is a bolt holding the PAIR to a bottom bracket. remove this. leave the bottom bracket intact as filter removal is required to get bolt out. 

reinstall these bolts into their correct holes and tighten. 
PAIR should now be hanging on 2 tubes. thick one and thin one. 

remove seat, lift tank and prop 
RH Side of air box, at the back is the connection for the thick tube. pull it off, and pull from the bike. using a suitable block off device, block off the connection on the air box (I put an M10 x 20 bolt in, and tightened it up) 

still on RH Side of bike, see the small tube going to the inner most vacuum connection on #4 Throttle body. blank the vacuum connection, (as I did, cut the tube just after where it goes through the black clip, and put a bolt in the end, clamping the bolt in the clip......temporary till I have the air box off again and I'll install a better block on the connection.) 

TAPPING THE HEAD 

Now the head tapping... 
If you don't know what you are doing, or have never done this before, this is probably not the place to learn!!.....get someone with workshop experience to do it, or guide you through the process. 

As such, all I shall say is 

Tap a 6mm thread into the head where the PAIR connection normally sits, lots of grease to hold the shards....blown out carefully with compressed air onto a greased rag.... 

Then, I used socket button head M6 x 10mm screws with copper washers underneath, loctited, and torqued...PAIR removed 

REFITTING 

Using the same technique as removal.. 
refit exhaust, refit radiator and oil cooler, cleaning joints before reinstalling the O ring connections... 

fill with oil, fill with water/antifreeze mix, 

CHECK WORK! 

check work, wipe all connections clean, start bike, check that Oil pressure light goes out ALMOST INSTANTLY...if not hit the kill switch...something is wrong!!! 


BURPING THE COOLING SYSTEM 

Let her idle, constantly checking your refitted connections for leaks, when the coolant starts to get below the filler cap level, keep topping her up until it starts to over flow. Cap on, let the bike run up to operating temperature....switch off. 
Using rag remove radiator cap, CAREFUL!!!!!.. 

Refill with coolant to filler neck....replace cap. Sit astride bike (get a firm footing) start bike and rock from side to side as far as you are comfortable with (more of a sever lean to one side, then to other rather than a rock)... 

Do this until fan comes on...stop bike, let cool then open radiator cap, refill to filler neck...replace cap. Job done. 

Just keep an eye on the coolant level in overflow and also operating temp. if it gets higher then you have an air pocket and needs more burping.. 

CHECK WORK! 2 

Check all joints for seeping.
Check oil level in bike.

REFIT PLASTIC 

refit plastic, not forgetting the insulating foam pieces....(okay, okay, they are in my rucksack at the moment!!! LOL ) 

AND FINALLY........ 

I would say here wipe grubby fingerprints...but if you used a rag to clean the metal bits of the tap as you were cutting the thread, as you should, then don't. you might get a bit on the cleaning rag. throw all the rags used away!...start afresh....or use them to mop up the oil you spilt on the floor you mucky pup!! 
job done 

Go ride!!

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