Still Won't Run at Idle

**KEITH KRAUSE** · 07-06-2003, 06:10 PM

For the high idle, I'd check the o-rings in the manifolds first. As for running rich, don't change jets if the bike is all stock and the carbs are also. Besides what you say you've checked, is the air filter clean? Is the ignition timing correct and do you have a good blue spark at the plugs? Are the float valves leaking any fuel out the bowl overflow lines? Are you sure all the jets are tight? Are all o-rings in the carbs in good shape? I'm not familiar with the carbs on your bike. Are they 'CV' with a diaphragm? If so, how is the diaphragm? Only if you have a similar pilot circuit as my '79 1000: The pilot screws are underneath and the air screws are on the side. Turning the pilots out is richer. Turning the air screws out is leaner. With carbs like mine, the pilots are generally about 1- 2 turns out and can be at different positions from the factory. The side air screws are generally out about 1 1/2 - 2 1/2 turns. A 1/2 turn on the air screws will make a little difference, A 1/2 turn on the pilots can make a big difference. If all the above checks out, you might try adjusting these screws.

**granny_rocket** · 07-06-2003, 08:16 PM

is the air filter clean?

Yes

Is the ignition timing correct and do you have a good blue spark at the plugs?

Timing on the '85 models cannot be adjusted because the ignitor takes care of all that, or is there a way to do it im not aware of?

Are the float valves leaking any fuel out the bowl overflow lines?

Im Not sure what you mean by this, but the leaking fuel im talking about is coming out of a breather tube off the front of the air box.

Are you sure all the jets are tight?

As tight as I could get them without stripping them.

Are all o-rings in the carbs in good shape?

Should be! I just replaced them, unless one happens to be bad....

Are they 'CV' with a diaphragm? If so, how is the diaphragm?

They are CV carbs and the diaphragms look to be in good shape

Here's a picture of my carb:

"adjustment number 1" is which - the air screw or pilot screw? I now that the 85 models had no way to control idle mixture - so then what is the actual name for this?

Thanks SO much for the input!!!
-al

**Anonymous** · 07-06-2003, 10:08 PM

I have an 83 with the same type carbs. the screws you have circled are set between 3 1/2 and 4 turns from being bottomed out on mine. I tried to adjust these about 1/2 turn in and it ran awful at lower rpm. From what I can tell this is the only low speed adjustment other than the idle stop screw that you adjust with your fingers.

**granny_rocket** · 07-07-2003, 06:22 AM

I was just thinking....what is the float height in accordance to the factory manual?
My Haynes says 20.5mm +- 1mm and I read someone else's post saying the float wants to be 22mm. Im sure its not that big a a difference...but you never know!

**KEITH KRAUSE** · 07-07-2003, 09:29 AM

If you have fuel leaking out of the air box or air box dump line, then you have float valves that are not sealing and possibly a bad petcock. This can make the bike run rich and also the fuel can enter the crankcase.You say it ran worse after you worked on the carbs. If you by chance mixed up the float valves they can leak. The valve and seat wear into each other and become a matched set. Sometimes even disturbing them will cause a leak.One or more just might be wearing out. I'm leaving right now for vacation but I'm sure you can find lots of info here about leaky float valves and petcocks. Good luck!

Still Won't Run at Idle

Still Won't Run at Idle

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