Technical Discussion Topics related to Technical Issues

Help with diagnosis?

Old Jul 5, 2017 | 08:41 AM
  #1  
michaelbc's Avatar
Thread Starter
Member
Squid
 
Joined: May 2017
Posts: 63
From: Surrey BC Canada
michaelbc is on a distinguished road
Help with diagnosis?

Greetings, I bought my '01 recently, and thought I'd cured the flat spot at 3k rpm by installing the correct dyno jets and resetting the needles as per the instructions. The PO had them wrong. While I was in there I balanced the carbs and removed the PAIR system. New plugs as well. Now the bike starts and idles fine, and accelerates smoothly with no flat spot, even goes well on the highway, but no burst of acceleration when I try to pass. It will accelerate, but feels like it's bogging down. I suspect I may have pinched one or both diaphragms when reinstalling, would that create my situation? I'd hate to get it back together and discover it was something else! Thanks for any insight.
Old Jul 6, 2017 | 06:54 AM
  #2  
xeris's Avatar
Senior Member
SuperBike
 
Joined: Sep 2010
Posts: 1,994
From: Bisbee, AZ
xeris is on a distinguished road
I don't think the symptoms match, but check the position fuel hose on the fuel valve.
Old Jul 6, 2017 | 09:10 AM
  #3  
smokinjoe73's Avatar
Senior Member
MotoGP
 
Joined: Jul 2007
Posts: 5,066
From: NYC
smokinjoe73 is on a distinguished road
Did you do the work yourself or did a shop do it?

Either way check that the vacuum hose is connected to the correct nipple. If not then you are not going to have good fuel flow and the bike would act like you described.
Old Jul 9, 2017 | 06:20 AM
  #4  
7moore7's Avatar
Senior Member
MotoGP
 
Joined: Jul 2010
Posts: 3,871
From: Phoenix, AZ
7moore7 is on a distinguished road
Look for PVLIR like Joe said- might be getting enough fuel to ride, but not enough delivery under heavy load.
Old Jul 9, 2017 | 09:47 AM
  #5  
michaelbc's Avatar
Thread Starter
Member
Squid
 
Joined: May 2017
Posts: 63
From: Surrey BC Canada
michaelbc is on a distinguished road
Originally Posted by 7moore7
Look for PVLIR like Joe said- might be getting enough fuel to ride, but not enough delivery under heavy load.
the bike will sustain 7k or more rpms, is that consistent? I'm getting back into it this week, need to replace the cam chain tensioners as well. Will report. Thanks
Old Jul 16, 2017 | 10:27 PM
  #6  
michaelbc's Avatar
Thread Starter
Member
Squid
 
Joined: May 2017
Posts: 63
From: Surrey BC Canada
michaelbc is on a distinguished road
So, the diaphragms look OK, no kinks etc, I have the correct (dynojet) springs installed. When I took the airbox off, the rear choke cable wasn't properly seated in it's holder. The rear plug was fairly carboned, while the front was the proper brown colour. I'm hoping that's all it was. I'll finish the CCTs and try it out.
Old Jul 16, 2017 | 10:33 PM
  #7  
captainchaos's Avatar
evil man of nothing
MotoGP
 
Joined: Jan 2006
Posts: 4,517
From: Boynton Beach, FL
captainchaos is on a distinguished road
Originally Posted by michaelbc
When I took the airbox off, the rear choke cable wasn't properly seated in it's holder.
Also make sure the plastic nut that holds the choke to the carb isn't broken, as they're known to do...
Old Jul 21, 2017 | 11:34 PM
  #8  
michaelbc's Avatar
Thread Starter
Member
Squid
 
Joined: May 2017
Posts: 63
From: Surrey BC Canada
michaelbc is on a distinguished road
Well apparently the current owner (me) was a bit ham fisted when putting the carbs back together; I have no idea how that choke cable got dislodged. Long story short - the new CCTs are installed and the bike is running beautifully. Thanks for all the responses. These really are great bikes!
Old Jul 22, 2017 | 02:31 AM
  #9  
smokinjoe73's Avatar
Senior Member
MotoGP
 
Joined: Jul 2007
Posts: 5,066
From: NYC
smokinjoe73 is on a distinguished road
Man those things will self destruct if you even think an impure thought before during or after the operation.

We have all broken them, thus the switch to the brass fittings from Polaris. Even if you let a shop do the work, they will break them (but never admit it.)

Glad to hear it worked out. Consider replacing those elbows.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
raceruss2003
Technical Discussion
4
Jul 6, 2012 12:03 PM
psyclown
General Discussion
25
Jan 11, 2010 01:10 PM
mattvdsande
General Discussion
8
Mar 16, 2009 11:12 AM
fishface
Knowledge Base
0
Apr 21, 2008 11:58 AM
Galaxieman
Technical Discussion
1
Jul 13, 2007 05:46 AM


Thread Tools
Search this Thread

All times are GMT -7. The time now is 09:55 PM.