Technical Discussion Topics related to Technical Issues

Carb Trouble?

Old 08-02-2010, 09:46 PM
  #1  
Junior Member
Squid
Thread Starter
 
mchawkmaster's Avatar
 
Join Date: Jul 2010
Posts: 26
mchawkmaster is on a distinguished road
Carb Trouble?

So I have a 98 S Hawk with a little over 11,000 miles on it. When taking off from a stop it will shudder and shimmy up until 2-3000 rpms then it runs awesome or atleast awesome to what I can compare it to. When sitting at idle and I go to rev it up to show off my new toy it will kind of stumble and then rev up nice. It is also slow to come down to idle engine speed.

Also when down shifting after a "hard" pull in say second or third gear it will back throttle normally until it hits 3000 RPM and will start popping. To my knowledge the PAIR system is not removed but will be soon.

Running a tank with Seafoam right now but the problem hasn't gotten better. Does this sound like the carbs need to be synched or something better/worse?
mchawkmaster is offline  
Old 08-02-2010, 11:04 PM
  #2  
Banned
MotoGP
 
Join Date: Aug 2007
Location: Lake View Terrace, CA
Posts: 5,942
8541Hawk will become famous soon enough
Sounds like the pilot jets are fouled.
8541Hawk is offline  
Old 08-02-2010, 11:28 PM
  #3  
Senior Member
SuperSport
 
ranchomice's Avatar
 
Join Date: Nov 2009
Location: Rancho Cordova, California
Posts: 677
ranchomice is on a distinguished road
Listen to that guy ^^^^
ranchomice is offline  
Old 08-03-2010, 05:56 AM
  #4  
Senior Member
Superstock
 
Join Date: Jul 2008
Posts: 320
evines is on a distinguished road
I agree about the pilot jets, but an easier thing to check first is exhaust leak. When I bought my bike, it was missing the gasket between the rear cylinder downpipe and mid-pipe. It was leaking pretty bad, and caused a hesitation around 3-4K and LOUD backfire around 3-4K when decelerating. I was sure some of my symptoms were carb related, and tried sea foam to no avail, but everything was fixed when I installed the gasket.
evines is offline  
Old 08-03-2010, 06:52 AM
  #5  
Junior Member
Squid
Thread Starter
 
mchawkmaster's Avatar
 
Join Date: Jul 2010
Posts: 26
mchawkmaster is on a distinguished road
Does fouled pilot jets just mean that they are gummed up or does it mean I need new ones? I am running my second tank of seafoam through the bike now (filled up 30 minutes ago) and it seams that should unclog them. Right?

@ evines
My bike is running a Two Bros high mount system. I'm actually going to pull the cans and mid-pipes off tonight and repack the mufflers to see if that may help. Looking from the headers and following them through the x-pipe and up the mid-pipe to the cans I haven't seen any form of gasketing but will know more tonight. What type of gasket is it?
mchawkmaster is offline  
Old 08-03-2010, 07:08 AM
  #6  
Senior Member
Superstock
 
Join Date: Jul 2008
Posts: 320
evines is on a distinguished road
It's an aluminum gasket that fits in between the male and female fittings (you can't see it looking at the pipe). It's extremely fragile and kind of a PITA to install without tearing it up. If you can't feel exhaust leaking out, then you are probably ok. The gasket is #6 below. And yes, I think fouled means clogged with crap. I would guess if it's too clogged, sea foam might not work. But you should be able to clean them out and not buy new ones.

evines is offline  
Old 08-03-2010, 07:21 AM
  #7  
Senior Member
Superstock
 
wyldryce's Avatar
 
Join Date: Apr 2007
Posts: 293
wyldryce is on a distinguished road
I certainly wouldn't expect the seafoam to do an adequate job of unclogging those pilots; they just aren't that big. You'll have a hard time fouling the mains, but the pilots are pretty easy to restrict enough to cause the "lean hang" you're describing. You're best off pulling the carbs and doing a thorough job with carb cleaner, cleaning all passages and pulling the jets and letting them soak in carb cleaner for a few hours. Some have had luck draining the gas (or just running it dry) and adding carb cleaner to the inlet lines and then shaking the bike a few times every hour or two for 24 hours, then emptying. If it t'was me, I'd be pulling the carbs.
And yes, evines, muffler gasket could cause the popping, but to me it sounds like 8541Hawk called it...sounds lean.
-R
wyldryce is offline  
Old 08-03-2010, 09:37 AM
  #8  
Fastest Color
SuperBike
 
FL02SupaHawk996's Avatar
 
Join Date: Jul 2007
Location: Lithia, FL
Posts: 2,091
FL02SupaHawk996 is on a distinguished road
here's what the slow jets look like
Attached Thumbnails Carb Trouble?-slow-jets.jpg  
FL02SupaHawk996 is offline  
Old 08-03-2010, 11:46 AM
  #9  
Junior Member
Squid
Thread Starter
 
mchawkmaster's Avatar
 
Join Date: Jul 2010
Posts: 26
mchawkmaster is on a distinguished road
Welp... looks like I'm going to be diving into the carb tear up party soon. Never done it before so i'm kind of excited about it. Is there any tricks or things that a noob like me should look out for when taking this on?

Thanks for the pic of the slow jets FLO2. Are these what some call the mixture screws or are those different animals all together? Where abouts are they located on the carbs?
mchawkmaster is offline  
Old 08-03-2010, 11:54 AM
  #10  
Fastest Color
SuperBike
 
FL02SupaHawk996's Avatar
 
Join Date: Jul 2007
Location: Lithia, FL
Posts: 2,091
FL02SupaHawk996 is on a distinguished road
Originally Posted by mchawkmaster View Post
Welp... looks like I'm going to be diving into the carb tear up party soon. Never done it before so i'm kind of excited about it. Is there any tricks or things that a noob like me should look out for when taking this on?

Thanks for the pic of the slow jets FLO2. Are these what some call the mixture screws or are those different animals all together? Where abouts are they located on the carbs?
different animule

here download this manual and have at it: https://www.superhawkforum.com/forum...ad.php?t=11365
FL02SupaHawk996 is offline  
Old 08-03-2010, 09:16 PM
  #11  
Junior Member
Squid
Thread Starter
 
mchawkmaster's Avatar
 
Join Date: Jul 2010
Posts: 26
mchawkmaster is on a distinguished road
Thanks for all the input guys and FL02, thanks for the link to the manual.

Would it be worth trying the Yamaha carb cleaner "trick" before I go and pull the carbs off the bike?
mchawkmaster is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Zedicus
Modifications - Performance
5
03-12-2007 11:09 AM
mks8882
Technical Discussion
9
10-19-2005 07:24 AM
apbrian112
Technical Discussion
7
09-28-2005 12:30 PM
wheeliefun996
General Discussion
9
03-11-2005 05:20 AM
uberhawk
Everything Else
0
09-16-2004 08:37 PM


Thread Tools
Search this Thread
Quick Reply: Carb Trouble?


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.

All times are GMT -7. The time now is 09:50 AM.


© 2019 MH Sub I, LLC dba Internet Brands