Mythos
Registered
Gen 2
PAIR Solenoid and Reed cover Removal/Block off Plates Installation
This mod reduces decel popping that becomes noticeable with aftermarket exhaust systems and is often considered objectionable. The mod nets about a 3/4 pound weight loss and it cleans up the engine bay as well.
It is necessary to cover the reed valves after the reed covers are removed. Block off plates are usually purchased or fabricated to do this. If Block off plates are purchased, I would recommend that flat bottomed plates such as those available from Schnitz be used. Some plates have a raised part which is designed to drop into the reed valve holes. This probably seats nicely in the hole but it requires that the reed valves be removed which looks as though it would be a little tricky. The reed valves are left in place with the flat bottomed block off plates.
There is a PAIR hose block that will be required. The Block off plates I purchased did not come with such a plug. I used a 5/16 in chair leg bottom purchased at Lowe’s (see Step 9) which fit very snug on the hose nipple. I would prefer that there be some sort of clamp (such as the spring clamp on the PAIR hose) to secure the cap just to be sure it could not be blown off by air box pressure. There are also rubber caps called screw protector caps in the hardware drawers at Lowe’s. A 3/4 inch screw protector cap looks like it would work excellently and it may be secured with the OEM wire spring clamp, a small hose clamp or sinched with a piece of wire.
Prop, hang or completely remove the fuel tank (see, https://www.hayabusa.org/forum/maintenance-do-yourself/168658-gen-2-how-remove-fuel-tank.html)
Remove the air cleanerbox (See https://www.hayabusa.org/forum/maintenance-do-yourself/168673-gen-2-air-cleaner-box-removal.html)
Tools:
5mm hex tool ratchet attachment
resistor terminator plug (got mine from Schnitz)
Use a 10 mm socket
torque wrench
Zip ties
5/16 inch id chair leg bottom
1. Remove PAIR reed valve covers using a 5mm hex tool ratchet attachment.
2. Disconnect the PAIR coupler.
3. Attach a resistor terminator plug to the coupler. A code will be triggered if this plug is not used.
4. Use a 10 mm wrench to remove the PAIR solenoid bracket screws from the frame directly above the exhaust headpipes.
The PAIR solenoid bracket bolts are located on the underside of the bracket. The photo I used to illustrate step 4 shows the bolt being accessed from below the triple tree where the radiator would be. This is a convenient way to access the bolts if the radiator has been removed however, it is not necessary to remove the radiator. You will be able to reach a 10mm box end wrench or ratcheting wrench down to them from the front of the engine compartment (see location in the photo with step 2, above).
5. Remove the PAIR solenoid, hoses and PAIR reed valve covers in one piece.
6. Leave the reed valves and gasket in place if the block off plates you have fit flush over the holes. If the plates drop into the reed valve holes, the reed valves will need to be removed. Install the block off plates. Use non permanent locking agent. Torque spec for bolts is 8 foot lbs (i usually torque about 15-20% lighter than spec in aluminum parts such as the engine block.
7. Zip tie the PAIR coupler wire to the grey wrapped top engine wire that connects to the spark plugs.
I also have the horn wire zip tied into the bundle because I removed my horn and plan to use the wire as a power source for something in the future.
Reinstall the air cleaner box (see https://www.hayabusa.org/forum/maintenance-do-yourself/168673-gen-2-air-cleaner-box-removal.html).
Plug the PAIR hose fitting on the air box.
A 5/8 inch id chair leg bottom purchased at Lowes works very well as a plug.
Total weight of Blockoff plates and plug is barely over 3 ounces. The scale does not register under .05 oz but switched to metric, the plug is 1 gram which is less than .02 ounce.
Parts Removede 15 oz
Parts added: 3.05 oz
net weight loss, 11.95 oz
PAIR Solenoid and Reed cover Removal/Block off Plates Installation
This mod reduces decel popping that becomes noticeable with aftermarket exhaust systems and is often considered objectionable. The mod nets about a 3/4 pound weight loss and it cleans up the engine bay as well.
It is necessary to cover the reed valves after the reed covers are removed. Block off plates are usually purchased or fabricated to do this. If Block off plates are purchased, I would recommend that flat bottomed plates such as those available from Schnitz be used. Some plates have a raised part which is designed to drop into the reed valve holes. This probably seats nicely in the hole but it requires that the reed valves be removed which looks as though it would be a little tricky. The reed valves are left in place with the flat bottomed block off plates.
There is a PAIR hose block that will be required. The Block off plates I purchased did not come with such a plug. I used a 5/16 in chair leg bottom purchased at Lowe’s (see Step 9) which fit very snug on the hose nipple. I would prefer that there be some sort of clamp (such as the spring clamp on the PAIR hose) to secure the cap just to be sure it could not be blown off by air box pressure. There are also rubber caps called screw protector caps in the hardware drawers at Lowe’s. A 3/4 inch screw protector cap looks like it would work excellently and it may be secured with the OEM wire spring clamp, a small hose clamp or sinched with a piece of wire.
Prop, hang or completely remove the fuel tank (see, https://www.hayabusa.org/forum/maintenance-do-yourself/168658-gen-2-how-remove-fuel-tank.html)
Remove the air cleanerbox (See https://www.hayabusa.org/forum/maintenance-do-yourself/168673-gen-2-air-cleaner-box-removal.html)
Tools:
5mm hex tool ratchet attachment
resistor terminator plug (got mine from Schnitz)
Use a 10 mm socket
torque wrench
Zip ties
5/16 inch id chair leg bottom
1. Remove PAIR reed valve covers using a 5mm hex tool ratchet attachment.
2. Disconnect the PAIR coupler.
3. Attach a resistor terminator plug to the coupler. A code will be triggered if this plug is not used.
4. Use a 10 mm wrench to remove the PAIR solenoid bracket screws from the frame directly above the exhaust headpipes.
The PAIR solenoid bracket bolts are located on the underside of the bracket. The photo I used to illustrate step 4 shows the bolt being accessed from below the triple tree where the radiator would be. This is a convenient way to access the bolts if the radiator has been removed however, it is not necessary to remove the radiator. You will be able to reach a 10mm box end wrench or ratcheting wrench down to them from the front of the engine compartment (see location in the photo with step 2, above).
5. Remove the PAIR solenoid, hoses and PAIR reed valve covers in one piece.
6. Leave the reed valves and gasket in place if the block off plates you have fit flush over the holes. If the plates drop into the reed valve holes, the reed valves will need to be removed. Install the block off plates. Use non permanent locking agent. Torque spec for bolts is 8 foot lbs (i usually torque about 15-20% lighter than spec in aluminum parts such as the engine block.
7. Zip tie the PAIR coupler wire to the grey wrapped top engine wire that connects to the spark plugs.
I also have the horn wire zip tied into the bundle because I removed my horn and plan to use the wire as a power source for something in the future.
Reinstall the air cleaner box (see https://www.hayabusa.org/forum/maintenance-do-yourself/168673-gen-2-air-cleaner-box-removal.html).
Plug the PAIR hose fitting on the air box.
A 5/8 inch id chair leg bottom purchased at Lowes works very well as a plug.
Total weight of Blockoff plates and plug is barely over 3 ounces. The scale does not register under .05 oz but switched to metric, the plug is 1 gram which is less than .02 ounce.
Parts Removede 15 oz
Parts added: 3.05 oz
net weight loss, 11.95 oz
