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08 Flapper mod

350K views 636 replies 267 participants last post by  Reaperbike 
#1 · (Edited)
OK, when I started this lil project I thought it was gonna be easy- at least it started that way (you'll see).

To start with you need to remove the 3 pop off plastic screws on the inner left and right fairings, right next to the top triple clamp.


These 2,


and this one,


pull slightly on the top plastic and there it is!!


Now here is where it gets interesting, unlike the 04-07 flapper mod, the diaphram pushes down on a door thats hinged on the bottom part of the intake tube, the door is also counter sprung so that it remains closed until the diapharm is activated by vacum pressure. Its set up in such a way that pulling the vacuum hose off, or removing the diaphram completely will leave the door permanatly closed because there is that damn spring pulling the door forward and thus closed.

I tried to take a pic but its inside the tube:

here you can kinda see the spring on the right, and the bottom arm of the diaphram. Again sorry for the pic quality but its inside the ram air tube and I had to hold a flashlight just to see it.
My solution was to pull off the diaphram completely, AND remove the spring which caused the door to remain permantly open. Sounds easy, but that spring is a PAIN IN THE ASS!!!!! It's far enough in the tube that you cant reach it with anything but the longest screwdriver.
By sticking my finger in the same hole the diapharm came out of and playing around (finger fucking) I got the back end of the spring off, then pulled stright forward from the front of the tube to get it completely out.
This is what I was left with, againg poor pic quality cause its so far inside the ramair tube:


After this its as simple as putting the plastic piece and the pop tabs back in and your done.

I did go for a short ride after and this had the same effect as the flapper mod on the 04-07, lil smoother/less heisitant on take off. I'm sure it added no HP but like I said it made the launch a lil smoother. Also I got no codes:th_salute:

I know this is a lil confusing cause of the poor pic quality but intill someone pulles the bike completly apart this will have to do, enjoy!
 
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#3 ·
This is what I removed, please not the large insect I removed as well:
 
#14 ·
No idea, there is also a diaphram and wires on the right side of the bike that you can see through the opening in the fairing.
 
#15 ·
any idea as to how the flapper works on the new bike? i know on the previous models, it'd close when you put it into gear and open at a certain speed or rpm. i had my '08 on the stand today, started it, put it into gear, and let out on the clutch. the flap stayed open the whole time. it's also open when the bike is off. at least it appears to be open
 
#16 ·
at least you lost some more weight.:thumbsup:
 
#17 ·
I put mine on the stand and started it also. Put it in gear and at first it appeared that the flap was open, but it wasnt. Its so far back up in the intake its hard to see.
 
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#18 ·
gotcha. i'm going to have to do this i guess. i was just wondering what the electrical connectors were for and if they had any bearing on the flapper
 
#19 ·
I had to get a flash light in order to see that far back in the intake tube.
Maybe soon someone will pull one completly apart and well get a better picture.
 
#21 ·
removing the complete flapper assembly can be tricky. the vacuum res. is located under the upper stay right across from the horn. remove both mids and disconnect each ram air duct from the mid so you can get the flaps out.

be careful removing your plastics or you will be buying new ones. removing them is not as easy as the 04-07's.
 
#24 ·
Just took out the flappers on my 08 this evening. Smoother/snappier in the lower RPMs. Also has a nice deeper growl to her when down lower.

I took the flaps out as well. You can just stick a long screw driver in there and pry them out of their hinge sockets. You just need to make sure you don't accidentally send them back in there really far. I almost had one of mine sneak back in there beyond my sight or reach. Luckly I had one of those long flexible magnet slash grabbers that reached back in there to get it. On the other side I just laid that same flexible magnet grabber thing on top of the door so when it cut loose it wouldn't go anywhere. I figured it couldn't hurt having the doors all the way out, plus it just seems like there is less to get in the way of good ole rammed air... and living at high altitude, I need all the air I can get
 
#26 ·
Hey all, well I had to move up here from the ol 600rr.net forum. Bought the 1000rr around two weeks ago, havent ridden it much the past few days as I need to get the oil changed. I am already at like 650 miles, was after the first week. That seats nice! Anyways I did the exhaust flap mod and was wondering if anyone else did? I havent noticed any difference in power, though it does sound a lot nicer! There is still another valve down in there but I am pretty sure that one may be beneficial to low end torque. Ill take pics if you all want.
 
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