I have a 2001 883 sporty that acts strangely at times. It runs pretty well at times, and others, it hesitates and coughes. I know this is a fuel/air problem, and from the way it hesitaties, it looks to be rich. But after it warms up, and i push the enricher all the way in, its fine until i get on the interstate, and then it starts hesitating and coughing again. I pull the enricher out slightly and it stops. I looked at the plugs which were replaced in the winter, and they are blackened. So again, the plugs say rich. but enricher fixes the problem, and that says lean... Which is it?

I have looked for the air/ fuel adjustment on the carb, but i cannot find it, and the factory manual does not have it shown. Where would I look for it?

 

Change the spark plugs and put a good 100 miles on em and then check them.

If you're pulling the enrichner out and that's fixing the problem that sounds lean.

 

change your plugs, and then change your habits.

When you start up the bike, this is how to do it.

with the bike off and cold, pull out the choke as needed to start the bike, then tighten the throttle lock screw under the right control. then start the bike normal, raise the idle a bit, and slowly push in the enrichener. ONLY use it for startup, the actual warming of the engine should be done with the choke pushed in, or not activated. this is how to foul up plugs almost dangerously fast.

first change your plugs, then use THIS start up procedure for at least 100 miles. then check your plugs.

fact is, if you keep it out while its warming, or worse, even ride on it with the choke out, even half way, you blacken your plugs and by the time the choke goes back in, and you ride the rest of the day normally, it still may not be enough to clean the plugs and your just seeing the results of your startups instead of the actual problem.

once you do this you should get a better reading of the plug.

Personally, I would look at your float level in the carb, and make sure there is no debris in the float hinge cuasing it to stick up or low changing the mixture. also put an inline fuel filter on the bike, and run high quality gas and some seafoam for a couple tanks.

it seems like debris is getting caught in the jets or making the float stick. and thats why its intermittent, becuase the vibration shakes it out.

 

Ok, I have actually been through the carb during the winter. I cleaned it, jets are in good condition. They are the slightly larger ones for the bike(I forget the numbers offhand), and I even ran fuel system cleaner through the entiere fuel system. enricher isn't stuck, and float level seems to be at the correct position.

If i can locate the adjustment for the fuel/air mix, I could fix this, im pretty sure. But I can't find it. Ive seen the location on other HD carburators, but there doesn't appear to be one here. Its surprising to me that there wouldn't be one.

 

your running larger jets with stock exhuast and AC?

Are you getting ANY backfire at all? or popping/crackling on Decel?

took me a while to find the mixture screw on my carb as well.

check out this site
http://www.harley-performance.com/harley-davidson-carburetor.html


Your first post was a little unclear, is the problem intermittent? or does it run badly all the time when the engine is warm? I assumed the problem was intermittent in my reply, but please clarify it

 

[/b]I had similar issues with my girlfriends '06 883L. Here is a write - up of the issues and attempts at fixing that I posted on another board recently.[/b]
[/b]
2006 Sportster 883L (carb)[/b]
[/b]
The bike was purchased new in June 2006. From day 1, it had an intermittent problem. Occasionally, when it was ridden in warm weather and motor was warmed up, it would cough/fart thru the carb when trying to start up from a stop light. To keep the bike from dieing at lights, you had to keep twisting the throttle. Accelerating hard, there was a flat-spot where the bike would just limp along for quite a while before taking off.

We took the bike back to the dealer and he explained that HD sets these bikes far too lean in order to meet EPA standards. He rejetted the carb – replacing the low speed jet with a #48 jet. (Stock is a #42.) He did not drill out the plug for the mixture screw, so I know he did not adjust that.

The bike ran okay for a short time, but then the same intermittent issues started again. I installed the SE intake/breather in the spring of 2007. The bike ran fine all 2007, so I assumed installing the SE intake had solved the problem.

Fast forward to 2008, and the same intermittent cough/fart thru the carb starts again, and all the other symptoms. I took the carb apart and found no crud and no obvious problems. I put in a #45 low speed jet, drilled out the mixture plug, and set the mixture screw 2 ¾ turns out. This made no improvement and all the issues were still there.

I tore carb apart again. Replaced the needle and spring with the needle and spring from a Dynojet kit. (I did not drill out the hole in the slide.) I put the needle c-clip in the 4th slot from the top and put in 3 washers. I also replaced the breather washer that had come with the SE intake kit with a couple washers that were a little thinner. (The washers in the SE intake kit were slightly thicker than 1/8” - .137”. I replaced them with washer that were slightly thinner than 1/8”) I thought this would allow the carb to fit a little tighter in the gasket between carb and manifold, perhaps giving a better seal.

At the same time, I replaced the cam position sensor because I had heard of similar issues to mine being caused by a bad cam position sensor.

After all these changes, the bike appears to be running absolutely flawlessly. Now the question is, did the mods to the carb solve the problem or was it a bad cam position sensor??? I am going to run the bike a few more days to make sure the intermittent problem is really gone. Then I will put the original cam position sensor back in and run it for a while. If the intermittent problems return, then I will have to assume the sensor was bad. If they do not, then obviously the mods to the carb were what the bike needed.

 

Here's a link to help you find the adjustment screw. http://www.nightrider.com/biketech/hd_cv_mods.htm
It also has some good information on the Keilin CV carb. As you look at the carb from the right side of the bike, the screw will be on the left side of the carb body identified with a slight protrusion. It is more toward the front half of the carb body. If the carb has never been adjusted, then the stamped metal cover has to be removed. This is done by drilling a small hole to start a screw, which then will allow it to be removed. There are only two screwdriver adjustment points on the CV carb. One is for the idle speed, the other is for the air/fuel. Remember, you are working upside down to find this point unless you take off the carb from the bike. It would be much easier to do it off of the bike but, it can be done with it on and, pulledoff of the intake manifold.

 

sounds like a smallair leak in the intake, and possible some crud in the tank plugging the filter.

 

I have Vance and hienes shorty duals for exhaust, and as far as i can tell, a stock air cleaner. Yes, there is backfiring and popping when i let off and ride the motor compression. And yes the problem is mostly intermittnet. I have also discovered that maybe the reason the enricher makes this problem stop is because it raises the RPMs. the carb farts only happen at low RPMs. Also, there does seem to be alot of fuel coming out of the carb, and onto the filer element. I always thought this to be a normal thing, but now i am not so sure.

The only time that i have had a real issue wiht the bike was when the ignition wires wore out, and started shocking my leg, and eventually stopped working altogether for one cylander. I replaced these about a week ago, and start-up was more confident sounding, but the problem has not gone away.

By the way, thanks to those of you who have finally shown me where that darn idle adjustment is. I should be able to take a better look at the carb and bike in a week or two, for now, i am just stateing the symptoms, and making observations from the surface.

Thanks

 

After driving the bike more this weekend, observing exactly when and where the bike is coughing, I am pretty sure that it is VERY rich. Also, taking josephgarcia's advice on the enircher useage and spark changing, the bike has not changed at all; it still has a dead portion in the throttle, and a cough.

The cough confused me at first because it seemed like not enough fuel, and therefore not firing. With more observation, the cough only happens after i speed up, and back off with the throttle. This tells me it has too much gas/ not enough air: overly rich.

Does this seem reasonable?