top end question - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Carbs and Fuel System
From the gas tank to the carbs
All fuel system discussion

 
LinkBack Thread Tools Display Modes
post #1 of 7 (permalink) Old 06-15-2012, 01:48 PM Thread Starter
Senior Member
 
Stones750's Avatar
 
Join Date: Jun 2011
Location: Littleton, CO
Posts: 223
iTrader: (0)
 
top end question

I was getting a bit wiley the other day and noticed my bike does not want to go past 7k rpm. It's almost like a rev limiter-this happens in any gear. Basically with wide open throttle it doesn't miss or hesistate untill 7,000 rpm then it starts to rap out, I'm pretty positive these bikes do not have a rev limiter and I'm at 140 on the main jets with drag pipes and ears shaved @ 5,280 ft. elevation. This problem was the same with 138 mains as well. Now it pulls better with the 140's but still cant get past 7k. Any ideas guys?

86 Vn750
Coastered
De-Goated
Ears shaved
"Custom Pipes"
"Custom Seat"
Apes
Stator Mod
Malteese led Turn Signals (Rear)
Paid 750.00$ for her in 2005 w/ 9k
Currently @ 23k and counting
Stones750 is offline  
Sponsored Links
Advertisement
 
post #2 of 7 (permalink) Old 06-15-2012, 01:53 PM
Senior Member
 
Join Date: Jan 2012
Posts: 619
iTrader: (0)
 
Where is your breather pipe do you have it cut to 45degree angle and stuck in the right ear, if it is caught by the wind rush it can cause a vacuum and bog the bike down.
Swagman is offline  
post #3 of 7 (permalink) Old 06-15-2012, 02:00 PM Thread Starter
Senior Member
 
Stones750's Avatar
 
Join Date: Jun 2011
Location: Littleton, CO
Posts: 223
iTrader: (0)
 
The carb breather hose is inside the frame tubing-theres a hole just under the tank that keeps the hose outta the wind -Ears shaved-

86 Vn750
Coastered
De-Goated
Ears shaved
"Custom Pipes"
"Custom Seat"
Apes
Stator Mod
Malteese led Turn Signals (Rear)
Paid 750.00$ for her in 2005 w/ 9k
Currently @ 23k and counting
Stones750 is offline  
 
post #4 of 7 (permalink) Old 06-15-2012, 03:12 PM
Old Truck Junkie
 
niterider's Avatar
 
Join Date: Jul 2007
Location: Roby Texas
Posts: 4,130
iTrader: (15)
 
What kind of air filter are you running?

02 honda sabre 1100
niterider is offline  
post #5 of 7 (permalink) Old 06-15-2012, 03:52 PM
Members who have donated towards server costs
 
JM2001's Avatar
 
Join Date: Mar 2011
Location: Rochester, New York
Posts: 1,803
iTrader: (1)
 
Quote:
Originally Posted by Stones750 View Post
I was getting a bit wiley the other day and noticed my bike does not want to go past 7k rpm. It's almost like a rev limiter-this happens in any gear. Basically with wide open throttle it doesn't miss or hesistate untill 7,000 rpm then it starts to rap out, I'm pretty positive these bikes do not have a rev limiter and I'm at 140 on the main jets with drag pipes and ears shaved @ 5,280 ft. elevation. This problem was the same with 138 mains as well. Now it pulls better with the 140's but still cant get past 7k. Any ideas guys?
Sure, at that elevation your jets should be at least 2 sizes DOWN. Too much fuel and thinner air.

JM2001

" Loud Pipes Risk Rights "

2001 Vulcan 750
marbled
TOC upgrade on ACCT
Air/fuel mixture set to 2 1/2 out
rectifier relocated
splines lubed
iridiums
decals removed
upgraded mirrors
Pic up coil mod done
degoated
All LED lighting
Upgraded Mosfet rectifier
JM2001 is offline  
post #6 of 7 (permalink) Old 06-15-2012, 06:34 PM Thread Starter
Senior Member
 
Stones750's Avatar
 
Join Date: Jun 2011
Location: Littleton, CO
Posts: 223
iTrader: (0)
 
Quote:
Originally Posted by JM2001 View Post
Sure, at that elevation your jets should be at least 2 sizes DOWN. Too much fuel and thinner air.
True, the elevation here does require two steps down with a stock setup. However most near sea level or between are running 140's with stock exhaust and the ear shave. I have straight pipes which lean the mixture. The problem was the same with 138 mains as well. It pulls stronger near the higher rpms with the 140's but even with 135's (which are confirmed to lean by a dyno) the problem still exists. It's not like a rich condition where you let off the gas and the bike resumes cruising. It is like hitting a rev limiter, it gets to 7k and bounces a little while making the same sound a bike with a rev limiter would. It will not rev past 7k even if I'm not at WOT (3/4 or less in a lower gear). The bike will accept WOT in second gear from 2300 rpm up to 7k. Maybe I'll just keep the old girl under 7k lol.

86 Vn750
Coastered
De-Goated
Ears shaved
"Custom Pipes"
"Custom Seat"
Apes
Stator Mod
Malteese led Turn Signals (Rear)
Paid 750.00$ for her in 2005 w/ 9k
Currently @ 23k and counting
Stones750 is offline  
post #7 of 7 (permalink) Old 06-16-2012, 02:08 AM
Old Truck Junkie
 
niterider's Avatar
 
Join Date: Jul 2007
Location: Roby Texas
Posts: 4,130
iTrader: (15)
 
Try your vaccuum hose to the intake and petcock. also the best air filters to use are the k&n pods.

02 honda sabre 1100
niterider is offline  
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

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 On
Pingbacks are On
Refbacks are On

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