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post #1 of 10 (permalink) Old 08-17-2008, 12:16 PM Thread Starter
 
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cold idle

Hello eveyone. I am new here and was hoping that I could get some information about my bike. It is a 99 with 31,000 mile on it. i have noticed that when I first crank it in the morning, it is skipping. When I put the choke on, it straightens out and runs smooth. I was tinkering with it today and found a tube coming from the right rear of the carb running to what looks like a vent system under the seat. If i crimp the line, the bike idles smooth, but when i uncrimp it, then the bikes idles a little rough. I was hoping that ya'll could help me try and diagnose this, or is this the ways that these bikes idle. I appreciate any information that you could give me.

Thanks.
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post #2 of 10 (permalink) Old 08-17-2008, 01:50 PM
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I think everyone here would just about say that these bikes have to be choked when cold until they warm up. You have to keep adjusting the choke, because the idle will keep increasing until warm. The line you see is for the carbs, if closed off it will most likely run crappy at higher rpm. Make sure the line is cut at a 45 degree cut so it is not blocking off suctiion when pushed back in to the right ear.

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post #3 of 10 (permalink) Old 08-17-2008, 03:12 PM
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That small vacuum line on the right side goes to the air valve which is under the seat, (and in front of the battery), unless the bike has been coastered and the valve has been removed.

(I just looked at your post again and it sounds like you still have the air valve under there.)

The bikes idle will change from closed choke to open choke, that's normal.

But after the engine is warmed, and you're not using the choke, is that when you notice the "skip" in the idle?
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post #4 of 10 (permalink) Old 08-17-2008, 04:17 PM Thread Starter
 
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Thanks for the info. The skip is more noticable when cold, but you can also tell it when it warms up also, not as bad though. When it is warm, it has a "lope"to the idle, but when i crimp this line, it smooths out.

Thanks.
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post #5 of 10 (permalink) Old 08-17-2008, 06:06 PM
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I believe he is talking about the line that vents the carbs, not the one that goes to the valve under the seat. What exactly does the carb vent, vent. Are they vents for the fuel in the carbs or vent to the diaphrams that operate the carb needles?? If they vent the carb needles, would that mean that one of the diaphrams may have a rupture???

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post #6 of 10 (permalink) Old 08-17-2008, 06:31 PM Thread Starter
 
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This line runs to a "valve" that has 2 hoses connected to it. These hoses runs to each cylinder.
i for got to mention that when i removed this line, there was vacuum on the line from the carb. I was looking at some pics that Crobins365 posted and the fitting that the line runs to is called a "rear carb vacuum port". Hope this helps.

Thanks.
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post #7 of 10 (permalink) Old 08-17-2008, 06:40 PM
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When you pinch off the hose the missing stops. Then the diaphram in the valve is ruptured. Temp fix, plug off line till the valve is replaced or do the marble trick and leave the line plugged off.

02 honda sabre 1100
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post #8 of 10 (permalink) Old 08-17-2008, 07:17 PM Thread Starter
 
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thanks niterider. I will marble it tomorrow. Will I have to adjust anything after i marble it?

Thanks.
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post #9 of 10 (permalink) Old 08-17-2008, 08:13 PM
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I adj mine but I don't even remember why. If it runs good I would not worry about it.
Someone else here may know more about the needle adj after marbleing.

02 honda sabre 1100
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post #10 of 10 (permalink) Old 08-17-2008, 09:21 PM Thread Starter
 
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Thanks for all the help.
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