Carb sneezing at 80-85 mph

Energy One

emcclary

Active Member
I just got my bike back from the dealer on its 2500 mi service. I told him that if I held the throttle at 80-85 mph the carb sneezes every now and then. If I crack it at that speed she will fly but holding at a steady throttle every couple of minutes she sneezes. Dealer of course couldnt replicate the problem but sure enough I ride her home and there it is. The dealer changed my jets when they put my hooker rebel widetails on when she was new but it wasnt until after the 500 mile service that I started running the higher rpms and speeds. I have tried making adjustments while riding but I cant get it to stop. I am thinking maybe I need a slightly larger intermediate jet. I dont know the jet sizes the dealer put in so I cant give you that info. Where do you guys think I should begin? I am thinking of switching to the triple x this winter.
 

LDO

The Cleaner
Troop Supporter
I would start with taking your carb apart and identifying what you have (jet size). Can't tell you if you are too fat or lean in either circuit without that info. Besides, it would be good for you to know this stuff for future mods.:D :D
 

slowrower

2007 Mastiff
Same Problem .. solved

LDO, I had the same problem, holding the throttle for any period of time would cause it to sneeze - not all the time but often. The dealer tech screwed in the fuel mixture (under the white cap) and backed it out two turns. It now 95% gone and running much better - he also said to open it counter-clockwise about 1/4 of a turn and try this. You want to get it so it just barley avoids sneezing otherwise it will be too rich and start fouling the plugs. The S&S site has the carb adjustment document you can download for free - its right on. Just don't touch the accelerator adjuster (forward of mixture). Good luck!
 

emcclary

Active Member
My plugs look good since i put the spike straight up but turning the gas/air mixture screw either way makes the sneeze worse. If I lean it it gets a lot worse if I richen it a eighth turn or so it still does it.
 

Gas Man

Cool isn't cheap
Calendar Participant
Sneeze is lean.
Exactly... if you can't adjust it with the accel pump then you need to go bigger on the int jet.

You can use the "remove your carb" thread to help get to it... look at post #1,2,7,8 to aid you in getting to your jets. No need to remove the carb... just have to drop the bowl.

To adjust the carb... with the bike warm...
(in=clockwise/out=counter)

if your idle is low... turn it up a bit...

now spin in the accel pump screw till it seats. Now spin it out 1.5 turns

now spin in your fuel/air mix screw till the motor sounds like it wants to die

now spin it back out counting 1/4 turns. Do it slowly to give the motor/carb time to adjust. Do this till the motor sound like it wants to die on this end. Now you have counted those turns and you have say 2.5 turns. Spin it back in 1.25 turns. Or middle to almost dead on each end.

Now adjust your idle to 1,000 rpms on the tach.

Now with a few quick stabs at the throttle see if the rpms come up fast like you would think or if it kinda hesitates then takes off. If it does hesitate then spin the accel pump out another 1/4 turn and repeat till you get what sounds good.

If that don't fix the sneeze... you can spin out the accel pump a bit more... but anything over 2.5 turns means you need a larger intermiediate jet.

 

LDO

The Cleaner
Troop Supporter
Copy all!

My point was to take a look at the jets so at least you know your base-line #s.

Also, there is a .pdf file that tells you exactly how to make all the adjustments on your E&G carbs. Has pictures and stuff too. I printed it out and put it in my service manual. I think I have it saved on my harddrive at home...unless Ray shows up with it!:D

When I get home from work, I'll get it posted as a sticky or sumthin. Gas, you know what I'm talking about right????

I set my acc pump screw about 2 years ago and haven't touched it since. Only problem I ever had was a 'wondering' idle but I stretched out my spring a bit and that cured it!
 

KRAUT

Member
Gas, not to argue with you but the acell pump should not come into play at a consistant speed/load. Sounds to me he needs to go up in jet size to fix the lean condition. When re-jetting it's appropriate to disable the acell pump.
 

Sinthroid

Member
sneezin

My carb did the same thing when it came back from XXX.
I called and they sent me a couple different "Air Bleed" jets. It's like a main jet just different dia size. Mine had a 44 and I went up to a 48 and took care of the problem. I was told that sometimes the transition point between the intermediate and the main could get a little too rich. Easy to get to.
Good luck!
 

Gas Man

Cool isn't cheap
Calendar Participant
Gas, not to argue with you but the acell pump should not come into play at a consistant speed/load. Sounds to me he needs to go up in jet size to fix the lean condition. When re-jetting it's appropriate to disable the acell pump.
I would normally agree but I have heard of some people fixing their problems with a adjustment. Of coarse its hard to diagnose a "sneeze" in a moving bike over the internet.... ya know. So the best I figure... give the person some good info and let them run with it.

Here's also a S&S Adjustment LINK that should further the help.

That PDF is what I have in my manuals... great piece!
 

emcclary

Active Member
Sorry for dropping out of the discussion I was in PA since Thursday and havent had a chance to get to the web. I am going to check the carb in the next week to see what jets are installed so I can post them. I'll try turning up the accel pump but it pulls like nuts even up past 110 whenever I crack her which leads me to think intermediate but once I open the carb I will have better info.
 

Black Dawg

Active Member
This has all the symptoms of a lean intermediate circuit (not a main jet issue). If all they did was change the main, they left you lean during cruise. The stock intermediate jet is a .0295. If that is what you have switch to a .031. With that cold, dense air in NJ a .033 might be in order.
 
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