Variable Air Intake Control Vacuum Tube - Wrist Twisters
 
Thread Tools Display Modes
post #1 of 10 Old 09-05-2008, 09:01 PM Thread Starter
 
Join Date: Aug 2008
Posts: 5
Rep Power: 0
 
Variable Air Intake Control Vacuum Tube

Hello everyone.

Just bought a 919 from a fellow member on board.

It's an 04 with just over 10k on the clock. The bike has been lurching and shifting in an unusual manner and for some reason or another I decided that the intake mechanism is the culprit.

I removed the side cover and then removed the the air cleaner cover. To my surprise there was no vacuum tube connected to the back of the air cleaner. There was only a circular hole on the back side of the cover with nothing attached.

Furthermore, wedged up at the base of the tank was the variable air intake control vacuum tube. It was plugged with a screw.

Having never owned a 9er I'm not exactly sure how it's supposed to look. Furthmore, I have no idea what might happen if I remove the screw and fail to reconnect it to the air cleaner mechanism.

Thoughts?

mylexicon is offline  
Sponsored Links
Advertisement
 
post #2 of 10 Old 09-05-2008, 09:12 PM
Tribunus Laticlavius
 
voodooridr's Avatar
 
Join Date: Jan 2006
Location: Salinas, CA
Posts: 4,601
Rep Power: 1
 
Thats called the "flapper mod" I think you'd be hard pressed to find even a mildly modded 9er that still has the flapper valve connected. I haven't noticed any difference on my '04 with the valve connected or disconnected, I've left mine disconnected just because I can.

Dan

voodooridr is offline  
post #3 of 10 Old 09-05-2008, 09:49 PM Thread Starter
 
Join Date: Aug 2008
Posts: 5
Rep Power: 0
 
Quote:
Originally Posted by voodooridr View Post
Thats called the "flapper mod" I think you'd be hard pressed to find even a mildly modded 9er that still has the flapper valve connected. I haven't noticed any difference on my '04 with the valve connected or disconnected, I've left mine disconnected just because I can.

Dan
Hmmmm.....thanks for the info.

What is the point of the flapper mod? Should I leave the screw in the vacuum tube?

mylexicon is offline  
post #4 of 10 Old 09-05-2008, 09:55 PM
287
Tirone
 
287's Avatar
 
Join Date: Jun 2008
Location: Orlando, Florida
Posts: 10
Rep Power: 1
 
With the vacuum tube in place the flapper door is closed below about 5k RPM. The idea behind the flapper mod is to make the intake less restrictive by keeping the door open at all times.

287 is offline  
post #5 of 10 Old 09-05-2008, 10:13 PM
Discen
 
Join Date: Jul 2007
Location: Charleston, WV
Posts: 208
Rep Power: 1
 
yes definately keep that vacuum line plugged.

barmatt80 is offline  
post #6 of 10 Old 09-05-2008, 10:13 PM Thread Starter
 
Join Date: Aug 2008
Posts: 5
Rep Power: 0
 
Quote:
Originally Posted by 287 View Post
With the vacuum tube in place the flapper door is closed below about 5k RPM. The idea behind the flapper mod is to make the intake less restrictive by keeping the door open at all times.
So I guess it's safe to ride on a long trip tomorrow?

Seriously, thanks.

mylexicon is offline  
post #7 of 10 Old 09-05-2008, 11:29 PM
919>food>beer
 
Jeef's Avatar
 
Join Date: Dec 2006
Location: o-town, FL
Posts: 1,151
Rep Power: 1
 
yeah its a honda... just make sure you check out the FAQ thread on this board, there area few issues with loose bolts that need loctite, if the previous owner was from here it probably is taken care of but it would be prudent to double chcek, especially the shifter bolt (lost mine before I check this site). there are a few other common problems like the starter wire breaking in the switch housing but no major engine or tranny problems.

Jeef is offline  
post #8 of 10 Old 09-07-2008, 10:05 AM
Burn-em Upus Asphaltus
 
rickard919's Avatar
 
Join Date: Apr 2008
Location: Calgary, Canada
Posts: 3,802
Rep Power: 1
 

Awards Showcase
Donation 
Total Awards: 1

Quote:
Originally Posted by Jeef View Post
yeah its a honda... just make sure you check out the FAQ thread on this board, there area few issues with loose bolts that need loctite, if the previous owner was from here it probably is taken care of but it would be prudent to double chcek, especially the shifter bolt (lost mine before I check this site). there are a few other common problems like the starter wire breaking in the switch housing but no major engine or tranny problems.
+1 I lost the shifter bolt on mine as well. 2000 miles from home and the rider behind me saw my linkage hanging. Walking back a quater mile I was lucky enough to find the bolt.

rickard919 is offline  
post #9 of 10 Old 09-07-2008, 05:17 PM
Church of the Holy Smoke
 
MotoCycho's Avatar
 
Join Date: Jan 2006
Location: SLC, UT
Posts: 1,085
Rep Power: 1
 
Quote:
Originally Posted by Jeef View Post
yeah its a honda... just make sure you check out the FAQ thread on this board, there area few issues with loose bolts that need loctite, if the previous owner was from here it probably is taken care of but it would be prudent to double chcek, especially the shifter bolt (lost mine before I check this site). there are a few other common problems like the starter wire breaking in the switch housing but no major engine or tranny problems.
Quote:
Originally Posted by rickard919 View Post
+1 I lost the shifter bolt on mine as well. 2000 miles from home and the rider behind me saw my linkage hanging. Walking back a quater mile I was lucky enough to find the bolt.
Mine was cross threaded on and the bolt broke when I tried to remove it. It would have never come off in a 1000 years. I had to use a dremel to cut the clamp bracket off the shifter shaft and order a new one. I forget why I had to take it off at the time but it was necessary for whatever I was doing. Anyway.. Just thought I'd share my entirely opposite experience.

- Rev. CYCHO -

tires.... it's what's for dinner!
MotoCycho is offline  
post #10 of 10 Old 09-08-2008, 04:35 AM
Franklin McGillacutty
 
riquefied919's Avatar
 
Join Date: Mar 2008
Location: Aurora IL
Posts: 1,181
Rep Power: 1
 
I preformed an radical flaperectemy on 9er removed it all door vacuum valve and pluged the line.

riquefied919 is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Wrist Twisters forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome