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Bike runs good when choke is out.

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Old Mar 11, 2011 | 09:45 AM
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Bike runs good when choke is out.

Bought my superhawk about a year ago and it ran ok but I did notice a "carb fart" and acceleration was not like the previous hawk I had ridin. I knew that I would have some work to do when winter came here in Ohio and took apart the carbs, adjusted TPS (+-500 ohms), inspected main jets(180 front & 185 rear), pilots (45) and needles two down from the top on both. As I looked in the carbs and talked to other members on this forum I found that I had a stage one Dynojet kit. Mixture screws were all the way in on the front cyclinder and 1-1/2 on rear. I demmeled them both and set them back to spec (2-3/4). I have DEVIL high mounts on the bike right now with stock air filter. With the choke pulled all the way out the bike will start and idle but when you go to close the choke it dies right away. I tried to keep the throttle open and close the choke at the same time and it is real sluggish and dies when you let go of the throttle. I have heard that some people go back to stock mains, needles (shim .040) and use 48 pilots and get better results but I wanted to through it out there and see if anyone had any advice. I'm thinking it has something to do with the mixture screws but I could be wrong.

Last edited by aaugsbu; Mar 11, 2011 at 11:53 AM.
Old Mar 11, 2011 | 10:41 AM
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Well you need to start with a couple of basics. When you reassembled the carbs, did you check to make sure you have the diaphragms seated correctly?

Another thing to check is the pilot adjustment screws. You said the front was all the way closed, so you might want to pull it to make sure someone didn't seat it too hard and damage it. While you are in there check the small "o" ring that is supposed to be in there. If you look at #6 on this break down:
http://www.hondapartsline.com/fiche_...1998&fveh=4077
You can see how it should be. It is kind of hard to make out but it is pilot screw, spring, washer, "o" ring. Sometimes the "o" ring gets dried out and splits or someone could have accidentally left it out.
Old Mar 11, 2011 | 10:49 AM
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I've got stock mains, 48 pilots, needles shimmed .020 and pilot screws 2 1/2 out, and it runs great all through the rev range with Yosh slip-ons.

Still has the occasional carb fart at sea level (only at idle), but that disappears once I get up to 1000 to 3000 feet, where my favorite canyon ride is located.
Old Mar 11, 2011 | 11:06 AM
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Originally Posted by 8541Hawk
Well you need to start with a couple of basics. When you reassembled the carbs, did you check to make sure you have the diaphragms seated correctly?
Yes, I doubled checked.

Another thing to check is the pilot adjustment screws. You said the front was all the way closed, so you might want to pull it to make sure someone didn't seat it too hard and damage it. While you are in there check the small "o" ring that is supposed to be in there. If you look at #6 on this break down:
http://www.hondapartsline.com/fiche_...1998&fveh=4077
You can see how it should be. It is kind of hard to make out but it is pilot screw, spring, washer, "o" ring. Sometimes the "o" ring gets dried out and splits or someone could have accidentally left it out.
I did inspect the pilot adjustment screws for damage and also made sure that o ring, spring, washer and screw were there. Should I try to adjust the adjustment screw in? They are at 2-3/4 turns out right now.
Old Mar 11, 2011 | 12:19 PM
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I had the rear velocity stack turned the wrong way would that make it act up? Also there is a electrical wire hanging from the gas tank. Is this the fuel gauge sensor wire?
Old Mar 11, 2011 | 12:56 PM
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No, and yes.
Old Mar 11, 2011 | 03:06 PM
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I adjusted the idle screw that controls the butterfly on each carb and got it to idle around +- 1000rpm without the choke on. It does alright until I turn the throttle and then there is a hesitation and then revs up. I turned the pilot mixture screws to 1-3/4 turns out. Any suggestions?
Old Mar 11, 2011 | 03:55 PM
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So it idles now with the pilot screws out 1 3\4 turns?

The problem is that you are running a DynoJet kit and I never personally have gotten one of those to work correctly.

You can try turning the pilot screws in some more and see how it runs.
Old Mar 13, 2011 | 03:09 PM
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8541 Hawk you are right the problem that I have with jetting the carbs is because of the dynojet kit. I have now taken the carbs out and changed settings four times to try to get it to act right. The closest I have gotten is the 6th needle setting down from the top and pilot mixture screws at 2 out. Throttle response now is alot better than what it was before. I can't help but keep wondering if it would act even better with stock needles (shimmed of course), stock mains, and 48 pilots. I'll keep my eyes open maybe someone on the forum has a set of stock carb parts they would like to sell. Thanks again for your help though. I don't know if I would have gotten things done had it not been for this forum.
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