SuperMoto Junkie banner

1 - 20 of 44 Posts

·
Registered
Joined
·
32 Posts
Discussion Starter #1
In a previous thread, I mentioned that the Airbox Flap was put in for Noise Emissions for drive by testing. I've decided to remove it for less clutter and complexity. Some people are removing the airbox door.

Here's how I removed the Airbox Flapper Solenoid and associated hardware;

Here are the tools used and a picture of what will be removed;



Screw Driver Flat Head
Screw Driver Phillips Head
5mm Allen Wrench
1/4" Socket Wrench w/ 8mm and 10mm sockets
1/2" Socket Wrench w 5mm allen attachment (not necessary but makes the radiator side cap screws easier to remove)
You will also need a 1/8" rubber cap from an auto parts store.

1. Remove all of the body panels. I removed seat, side covers, rear fender, both front air directors, unclip the ECU.



2. Loosen the 3 screws that hold the gas tank on. Now you have access to the vacuum line under the tank. You can trace the vacuum line that goes to the throttle body because it attaches to the Black Plastic cylinder (the service manual says it's a Surge Tank). Pull the vacuum line from the throttle body and put a 1/8" rubber cap on the port. THE PORT NEEDS TO BE CAPPED.

When pulling the rubber vacuum lines out, it's easier to detach the lines from the surge tank. I didn't bother trying to move the main wiring harness. It's not necessary if you just pull off the vacuum lines from the various parts.



3. Next unscrew both the Surge Tank (black round thing) and the Intake Solenoid (behind the Surge Tank).

4. Next remove the Solenoid that controls the Airbox Flap. You can do this by rotating the solenoid Counter Clockwise (if not try clockwise, I forget the exact direction). The solenoid will pop out. You will need to put a small screw driver down the airbox opening and pry the clip off. Here's what it looks like without the solenoid and associated hardware.

5. To keep the Airbox flap in the down position, I drilled a small hole in the flap and the plastic directly below it. I used a 5/8" long self tapping screw to secure the flap (see picture).



6. Here's a picture showing everything removed.



The removal was a 45 minute job.

A tip on removing the vacuum lines from the fittings is to use a flat head screw driver and pry between the vacuum line and part. If you try to pull it off, the rubber will cinch tighter around the fitting.

Overall weight saved was not much, maybe 1.5lbs but there's much less complexity and clutter under the seat and to the bike in general.
 

·
Registered
Joined
·
32 Posts
Discussion Starter #5
Ride and Fly - The Airbox flap in the down position is open and not the other way around. You will be able to tell once you remove the seat.

SkiCoach - In emailing Trail Zone magazine about why they removed the Airbox Hardware on their WR250R project bike, the response was that this Airbox Flap was used for Noise Emissions when doing Drive by Testing. I asked if there was any negative effects and they said no.

Doing this mod is the same as removing the airbox door but you get rid of all of the clutter involved with the Airbox Solenoid. There is one electrical connection but it does not report to the ECU so it won't give you a CEL.

In my quick spin around the block, everything performed as should.

Albarelli - Your welcome. Let me know if you have any questions.

My next thing will be removing the lines that went to the Charcoal Can. I've already removed the can but still have the lines. I've learned that the gas line is a vent that is required by CA. It's used to relieve pressure when pumping gas. Looking at the microfiche part numbers, the 49 state WRR/X has a different tank and gas cap. Most likely the 49 state cap vents. There's another line that runs off of the throttle body. I plan on capping this off. I'll let you know what happens.

Side note the 49 state fuel tank is $289. The CA fuel tank is $1075! :eek: Also the fuel capacity in the CA model is lower. :rant:
 

·
Registered
Joined
·
1,918 Posts
i already pulled all the lines for the charcoal can. i think my thread with pics is still here somewhere....

i am going to do this mod when i put my power commander on this weekend.
 

·
Registered
Joined
·
1,202 Posts
Side note the 49 state fuel tank is $289. The CA fuel tank is $1075! :eek: Also the fuel capacity in the CA model is lower. :rant:
Same deal for the DRZ. Different tanks/caps for CA models, and the caps/tanks are not interchangeable, as in, you cant use a CA tank w/ a 49 state cap and vice-versa. I wonder if the WR is the same way. $1075 for a fuel tank! :rolleyes:
 

·
Registered
Joined
·
239 Posts
I'm nervous about doing the K&N and the filter mod. I know the bike is FI but I still get nervous that the bike may get hard to start at some point or run badly at some rpm or maybe run a little to lean...can anyone make me feel better about it??? lol. :lol:
 

·
Registered
Joined
·
217 Posts
I'm nervous about doing the K&N and the filter mod. I know the bike is FI but I still get nervous that the bike may get hard to start at some point or run badly at some rpm or maybe run a little to lean...can anyone make me feel better about it??? lol. :lol:
Do the mod and just monitor your spark plug on a regular basis, best way to tell if it is running lean or not. it will be apparent by a whitish color and/or bright white speckles.

If it's a light brown color then you are good :D
 

·
Registered
Joined
·
239 Posts
Do the mod and just monitor your spark plug on a regular basis, best way to tell if it is running lean or not. it will be apparent by a whitish color and/or bright white speckles.

If it's a light brown color then you are good :D

It's not the easiest task to get to that plug all the time. :) But I appreciate the answer. It's one that I knew in my head but these new 4 strokes put the plug so far in the motor it's crazy
 

·
Registered
Joined
·
1,202 Posts
You can look at your spark plug t'il you're blue in the face and it'll tell you one thing: absolutely nothing. You can't read a plug w/ additive laden modern fuels in a 4-stroke. These ain't 2-strokes (unfortunately).
 

·
Registered
Joined
·
806 Posts
MPFab did some dyno work and stepped through several of the mods. His results (actually measuring AFR along with the dyno) was that the flapper mod plusheader and slip on exhaust got him into the upper 13's air-fuel ratio. Nothing to worry about there.

After that he pulled the door off the airbox, it did run too lean (15+).

Here's one of his posts over at TT (more stuff in that thread too):

http://www.thumpertalk.com/forum/showthread.php?p=6615645#post6615645

So there's some actual measured data. :thumbup: The flapper mod plus some exhaust work does show some benefits and shouldn't be a problem, but if you open up the airbox further than just the flapper, then you may need to do something to add fuel.
 
1 - 20 of 44 Posts
Top