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post #1 of 11 (permalink) Old 07-25-2011, 09:23 AM Thread Starter
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Idle problems

My bikes been running really rough it just doesnt idle right. it starts up no problem but then you have to keep blipping the trottle or leave the choke open. it also sounds like the bike is starving for gas even when holding the throttle open at a steady rpm, misses while riding, and sometimes back fires when reving at higher rpm. However it's not consistent...a few times it ran perfect...the only thing that has been consistent is that when near 1500 rpm or below it starts to starve for gas and dies out. I had put 2 cans of sea foam in 2 full tanks of gas and no difference wha so ever. there has been no mods to the bike...Im not that mechaniclly inclined so need all the advice i can get.
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post #2 of 11 (permalink) Old 07-25-2011, 03:53 PM
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Sounds like your jets are clogged .... the best fix would be to pull the carburetors, disassemble, clean - making sure to clean the tiny holes in the jets, reassemble, and install. If Seafoam isn't working that's generally the next step. It should take you about a day your first time with proper instructions.
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post #3 of 11 (permalink) Old 07-25-2011, 04:11 PM
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Quote:
Originally Posted by bigpakapump View Post
My bikes been running really rough it just doesnt idle right. it starts up no problem but then you have to keep blipping the trottle or leave the choke open. it also sounds like the bike is starving for gas even when holding the throttle open at a steady rpm, misses while riding, and sometimes back fires when reving at higher rpm. However it's not consistent...a few times it ran perfect...the only thing that has been consistent is that when near 1500 rpm or below it starts to starve for gas and dies out. I had put 2 cans of sea foam in 2 full tanks of gas and no difference wha so ever. there has been no mods to the bike...Im not that mechaniclly inclined so need all the advice i can get.
Before you do the carb thing I had the same problem and I found that there is a black knob on the left side of the bike that adjusts how much gas and how it idles. It is worth starting the bike and turning this knob. Before doing this I had to run with choke 1/2 on to keep bike running.


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post #4 of 11 (permalink) Old 07-25-2011, 04:23 PM
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Quote:
Originally Posted by GreenHorn View Post
Before you do the carb thing I had the same problem and I found that there is a black knob on the left side of the bike that adjusts how much gas and how it idles. It is worth starting the bike and turning this knob. Before doing this I had to run with choke 1/2 on to keep bike running.


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The black knob is indeed your idle adjustment but it would only account for the idle problems and not the poor running condition while riding. If his slow jet is fully clogged he would have the same exact symptoms, and I'd suspect his main jet might be partially clogged as well.
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post #5 of 11 (permalink) Old 07-25-2011, 05:04 PM
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What about that vacuum hose that fits into the right ear, Ive seen post on here about that line either being blocked at the end or just out in the open. causing problems like you mention. Maybe someone else on here can explain what that line does, im not to sure.
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post #6 of 11 (permalink) Old 07-25-2011, 05:54 PM
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Quote:
Originally Posted by ifixf18s View Post
What about that vacuum hose that fits into the right ear, Ive seen post on here about that line either being blocked at the end or just out in the open. causing problems like you mention. Maybe someone else on here can explain what that line does, im not to sure.
If the carb vent hose that plugs into the slotted hole on the back of the right ear falls out and hangs in the wind, it can cause similar stumbling and rough running at speed, because air is forced into the hose which increases pressure in the carb float bowl.

Picture of slotted hole on the back of the "ear".
http://www.flickr.com/photos/leekayd...7600772238066/

However an unplugged vent hose can`t account for all the syptoms, I don`t believe.

Use the black idle adjustment knob on the left side to set idle at 1100 rpm when the engine is warm to see if that helps cure the symptoms.

But I tend to agree with vp that the jets probably need to be cleaned.

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post #7 of 11 (permalink) Old 07-25-2011, 08:49 PM
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I had a problem with the idle when the bike warmed up. My idle would hover between 1100 and 2300. Sometimes I could bring it down with a blip of the throttle sometimes not. It turned out to be an air leak on the rubber intake manifold. Something you may want to look at.

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post #8 of 11 (permalink) Old 07-26-2011, 02:11 AM Thread Starter
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I had to replace the idle knob because it was broken from previous owner. The right vent hose is fitted snugly into the right ear. It is possible to be clogged jets according to my father in law. we checked the air filter ( OEM ) and it just crumbled to the touch and found a lot of debris on the inside of the screen. So were almost positive that all that foam is now in the carbs. were going to take apart the carbs probably later today. does anyone know what size jets i should have in there being im a t sea level?
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post #9 of 11 (permalink) Old 07-26-2011, 12:27 PM
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Quote:
Originally Posted by bigpakapump View Post
I had to replace the idle knob because it was broken from previous owner. The right vent hose is fitted snugly into the right ear. It is possible to be clogged jets according to my father in law. we checked the air filter ( OEM ) and it just crumbled to the touch and found a lot of debris on the inside of the screen. So were almost positive that all that foam is now in the carbs. were going to take apart the carbs probably later today. does anyone know what size jets i should have in there being im a t sea level?
I'm at sea level and the original jets work great for me. The carbs are going to be a huge project the first time you do them, but [hopefully] you are a quick learner. Plan for a full 12 hours the first time and around 3-4 hours for every time after that. If this is the first time the carb has been opened I also recommend replacing all the o-rings ... there are 3 major ones per carburetor, if I remember correctly, along with the air cutoff valve diaphragms, which will run you about 30 a piece, if you go to the dealer and look into replacements. In total it should cost you under 100 and a day of your time. Take pictures before you disassemble or you will regret it when you're done. You'll memorize the lines soon enough. ALSO ... you will probably not find the small cotter pins used in the throttle assembly anywhere, and I found that standard sized staples work fine. Good luck.
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post #10 of 11 (permalink) Old 07-27-2011, 04:40 PM
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Mine ran a little rough when I bought it and had to always choke it when starting even when warmed up. I pulled the covrs off the airbox and found the foam was about gone too. I installed fresh foam filters and oiled them and it made a big difference in starting and having to choke it just to sart it.
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