DIY Air Intake System (AIS) Block Off Install

We've all seen those really cool AIS block off plates, and they're not that expensive or difficult to install. Why do we need them? Some will say weight, but they weigh naff all so I call that a wank. I fitted them to the FZ1, and immediately that annoying popping on deceleration was completely gone. It's no surprise that the R1 with the GYTR pipes is popping and carrying on like the guns of Navarone.

Yamaha's AIS - pumps fresh air into the exhaust to cheat CO emissions testing

Time to fix all that popping. But I couldn't be bothered waiting days (more like weeks) for the parts to turn up... and I had some stuff in the shed I figure I can achieve the same result.



This is all you'll need:

Pliers, #2 Phillips, flat blade, stumpy flat, 5mm hex key, 

1/2" carby bungs (x3), stainless steal hose clamps (x3), zippy tie

As always, you'll need a rag (not shown)

The three 1/2" carby bungs

1. Lift the tank; remove the rider seat, remove the two phillips screws retaining the dress panels, slide panels forward to release them. There is no need for force. Remove the 5mm front tank bolt just behind the head stem, remove the two 5mm hex head bolts from the side of the tank. Lift the tank and support however you prefer. Fanatics might like to completely remove the tank. Damn fanatics.

Tank side bolt under dress panel

Lifted tank supported on a rod

2. Disconnect the fuel line to the airbox; pull up the orange sleeve, pinch the blue buttons, gently remove the fuel line, there is no need for force it should disconnect easily. Catch fuel dribbles with a rag.

3. Disconnect the injector loom; follow it down to adjacent to the chassis. Again, no force needed, just a gentle press of the clip and the connector should come apart easily.

4. Remove the phillips screws, remove airbox lid.

5. Disconnect the upper velocity stacks; the plastic control arms attach with a 'C' shaped cross section and you can gently pop these apart. Remove both the upper and lower control arms to allow complete removal of the upper velocity stacks. Disconnect the servo push rod (with the white block) is the same fashion.

Upper velocity stacks removed

6. Remove the six hex head bolts retaining the lower velocity stacks.

7. Remove the lower airbox; as you lift it out, you'll need to trace the servo motor loom and disconnect it. You'll also need to disconnect the two 1/2" air hoses (one at the rear, one on the throttle side), and gently persuade the air intake duct to disconnect.

Removing the airbox lower - Throttle side air hose

Removing the airbox lower - Servo motor loom

8. Remove the airbox intake funnel; disconnect the blue connector attached to the sensor, and slide the opaque connector off it's retainer. Extract the intake funnel from the intake boots; the intake boots from each side intake tube feed inside the intake funnel. They are pretty flexible, so a little wiggling is in order. There is a grey plastic nipple in the middle of the funnel, surrounded by a rubber grommet... apply pressure to the nipple as you extract the funnel.

Blue connector disconnected, opaque connector removed from it's retainer

Intake funnel. 

Note the grey nipple-like thing and grommet in the middle; press here!

9. Remove the AIS motor and associated hoses; pretty easy and shouldn't really need explaining.

AIS about to be removed!

10. Fit the 1/2" carby bungs to the AIS intake ports; secure with stainless steel hose clamps. Don't over tighten, just make them secure.

Carby bungs fitted to AIS ports and secured with hose clamps

11. Zippy tie the opaque AIS loom connector; to the adjacent loom to ensure it doesn't interfere with the radiator fan.

12. Fit the 1/2" carby bung to the throttle side airbox lower AIS port.

13. Assembly is the reversal of the procedure above! You should have fitted just the rear air hose to the airbox lower.

Now when you close off the throttle on deceleration, Vietnam veterans won't have flashbacks!

UPDATE: More photos and description of an AIS block off plate installation on the R1 forum. You might need to be logged in to see the pics, though.