Carb Trouble?
08-02-2010, 09:46 PM
#1
Junior Member
Squid
Thread Starter
Join Date: Jul 2010
Posts: 26
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?
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?
08-03-2010, 05:56 AM
#4
Senior Member
Superstock
Join Date: Jul 2008
Posts: 320
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.
08-03-2010, 06:52 AM
#5
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Squid
Thread Starter
Join Date: Jul 2010
Posts: 26
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?
@ 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?
08-03-2010, 07:08 AM
#6
Senior Member
Superstock
Join Date: Jul 2008
Posts: 320
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.
08-03-2010, 07:21 AM
#7
Senior Member
Superstock
Superstock
Join Date: Apr 2007
Posts: 293
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
And yes, evines, muffler gasket could cause the popping, but to me it sounds like 8541Hawk called it...sounds lean.
-R
08-03-2010, 11:46 AM
#9
Junior Member
Squid
Thread Starter
Join Date: Jul 2010
Posts: 26
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?
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?
08-03-2010, 11:54 AM
#10
Fastest Color
SuperBike
Join Date: Jul 2007
Location: Lithia, FL
Posts: 2,091
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?
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?
here download this manual and have at it: https://www.superhawkforum.com/forum...ad.php?t=11365
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