misfire at idle, backfiring while under load, and stalling
#1
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This just started happening. Once it warms up it will not icle right and it misfires and backfires then stalls. It does it at idle and while riding. We cleaned the carb and replace the plug. I do run 105 low lead all the time but have been doing it for 6 monthes now with no trouble.
I have:
Aluminum Air Box
K&N
jet kit
Exhaust - Pro Circuit
I have:
Aluminum Air Box
K&N
jet kit
Exhaust - Pro Circuit
#4
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Did the problems start after the rejetting?
It idles better when cold, than warm? Good chance the idle circuit is too rich.
Is it a stock size pilot jet? How many turns out is the mixture screw?
When it starts to run crappy...if you pull the choke on...does it get better, or get worse? You can do this at partial throttle as well, if thats where it runs crappy.
If it gets better...the jetting is lean. If it gets worse..the jetting is rich.
It idles better when cold, than warm? Good chance the idle circuit is too rich.
Is it a stock size pilot jet? How many turns out is the mixture screw?
When it starts to run crappy...if you pull the choke on...does it get better, or get worse? You can do this at partial throttle as well, if thats where it runs crappy.
If it gets better...the jetting is lean. If it gets worse..the jetting is rich.
#6
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The problem just started....i had it running for about 8 monthes with no problems at all.
it is fine when it is cold i can ride it for about 5 minutes then it starts running bad.
i am not sure of the sizing on the jets but like i said it was running perfect since i got about a year ago now then it just started last week.
it runs bad threw the whole range of the throttle and the choke does not do anything to help the problem. if anything it just stalls when i turn it on i cant keep it running even giving it gas.
I really dont think the jetting is the problem because it was running fine and just started. I pulled the carb completely apart cleaned and put everything back the way it was. I had something similar to this and it was when the intake pipe fell off the carb.
yes it has enough gas
it is fine when it is cold i can ride it for about 5 minutes then it starts running bad.
i am not sure of the sizing on the jets but like i said it was running perfect since i got about a year ago now then it just started last week.
it runs bad threw the whole range of the throttle and the choke does not do anything to help the problem. if anything it just stalls when i turn it on i cant keep it running even giving it gas.
I really dont think the jetting is the problem because it was running fine and just started. I pulled the carb completely apart cleaned and put everything back the way it was. I had something similar to this and it was when the intake pipe fell off the carb.
yes it has enough gas
#7
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It almost has to be a carb or fuel related problem. If it was electrical, it would act up cold too.
Make sure the tank vent and the carb vent are open, and not restricted. When it stalls, does it restart ok? does it then run for a bit before acting up? Check to be sure the intake tube is tight and leak free.
Make sure the tank vent and the carb vent are open, and not restricted. When it stalls, does it restart ok? does it then run for a bit before acting up? Check to be sure the intake tube is tight and leak free.
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#8
#9
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Look at picture 6 in my gallery. The brass tube which sticks up in the float bowl is the vent, its connected to the rubber hose at the bottom of the float bowl. Sometimes that rubber hose gets blocked by dirt or mud, and then the float bowl wont vent.
When it restarts...is there black or dark smoke in the exhaust?
If you run with the lid off the air box, will it run better, when its warm? If you go far a short ride with the lid off, will it still stall?
If that isnt the problem, then I think youre gonna have to pull the carb and look it over good again. Are the jets loose? How many turns out is the mixture screw?
When it restarts...is there black or dark smoke in the exhaust?
If you run with the lid off the air box, will it run better, when its warm? If you go far a short ride with the lid off, will it still stall?
If that isnt the problem, then I think youre gonna have to pull the carb and look it over good again. Are the jets loose? How many turns out is the mixture screw?
#10
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08-01-2015 04:05 AM
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