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Missing at constant speed?

For a quick and easy check of float height put some clear plastic pipe on the float bowl drain secure the pipe to the side of the carb open the drain screw fuel level will show in the pipe
Have the bike upright when you try this
float bowl should be about 3/4 full

Brian
 
For a quick and easy check of float height put some clear plastic pipe on the float bowl drain secure the pipe to the side of the carb open the drain screw fuel level will show in the pipe
Have the bike upright when you try this
float bowl should be about 3/4 full

Brian

Drain screw is visible looking between the cylinders at about deck height
 
How do you attach tube too drain? Just cram it in there?
 
Remove air cleaner and back plate look under float bowl from right side of bike you should see a black overflow/drain pipe held on with a wire clip pull it off the fitting and replace with similar diameter clear plastic
A wee bit of heat from a heat gun will soften the pipe and allow it to easily slip over the thicker end of the fitting

Brian
 
So, all the parts carbs I have including the one on the bike. None of them have a overflow tube or drain screw. Must have been an early model feature that the EPA had done away with. I'll just take it off and do the 18 deg. angle measurement check.
 
So, all the parts carbs I have including the one on the bike. None of them have a overflow tube or drain screw. Must have been an early model feature that the EPA had done away with. I'll just take it off and do the 18 deg. angle measurement check.

That't the right way; do it once and do it right. Carb tuning is best done one step at a time; make more than one adjustment at a time and you don't know which adjustment had which effect.:58: If you are not familiar with tuning the CV carb, check out the Night Rider site or any of the various CV carb tuning sites. Once you get the jetting close, you can do a couple of plug cuts to get a better feel, or, if a dyno is available, just a couple of easy pulls to read AFR is worth the $30-$50 it might cost. The main complaint I hear about the CV carb is the lag time between the twist of the wrist and response which is typical of a vacuum operated slide; the reason many change to a Mikuni with a cable operated slide. The CV response can be improved with a lighter slide spring and opening up the vacuum port in the slide.

If you look at flow comparisons between a Keihin CV carb and a comparable Mikuni, you will see that the difference in flow is negligible across the RPM range. The CV is good carb when set up properly.:D
 
So, all the parts carbs I have including the one on the bike. None of them have a overflow tube or drain screw. Must have been an early model feature that the EPA had done away with. I'll just take it off and do the 18 deg. angle measurement check.

I think you are right, the drain screw and the overflow tubes were on my 92,97 and I do believe my 2000 fxd
 
Pulled carb and set a level on the bench and shimmed it level. Put my 18 deg. wedge of wood down. Set the carb and measured with a micrometer. It was out of spec. greater than .50. So I adjusted to the high end of the spec. Re-installed and its the same. Still some popping at constant speed. Tried pulling the enrichener out while rolling to see if more fuel would help and it made it worse.

The Dyno/AFR run is a good one. Only bike Dyno I know of is at the HD Dealer. Not going there! I'll figure it out if its the last thing that happens.....

Thanks for all the info. so far.
 
Pulled carb and set a level on the bench and shimmed it level. Put my 18 deg. wedge of wood down. Set the carb and measured with a micrometer. It was out of spec. greater than .50. So I adjusted to the high end of the spec. Re-installed and its the same. Still some popping at constant speed. Tried pulling the enrichener out while rolling to see if more fuel would help and it made it worse.

The Dyno/AFR run is a good one. Only bike Dyno I know of is at the HD Dealer. Not going there! I'll figure it out if its the last thing that happens.....

Thanks for all the info. so far.

Made it worse? As in still popping? That should have fattened it up if it were lean? You sure you do not have an air leak?
 
Bodeen,

Sorry Your having Troubles with it working like I thought it would.:small3d023:

Is that carb Seated into the rubber gasket enough at the manifold?

signed....BUBBIE
 
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