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Carburetor gasket.

Still a little cough when slightly opening the throttle. It's like I can't cruise slowlynin that range. I can work around it if I have to. Is that just a normal occurance?
I think the real solution is to go up one jet size. The Jets in it now are 42 and 160.
I've checked for intake leaks, also the intake seals are new.
 
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If your bike is 1988 883 sportster I would have expected the jets to be 45 for slow and perhaps 170 for the main as the smaller jet sizes started about 92 by that time the cv carb on the sportster had an accelerator pump
I think the 88 was the first year to the cv carb and they did not have an accelerator pump but had a steeper taper on the slide needle to try and make up for the lack of accelerator pump
all those are assumption that the bike is an 88 and still has the stock cv carb

Brian
 
It is a 1988, but the motor is a 2001, when I got it, it had an S&S carb on it which never ran well. I bought a compete carb setup from a 2001 to replace the S&S.
I just rode about 35 miles, and it seemed to run great, except for when I was driving slowly through a parking lot, when it coughed a few times. I'm at about 3.5 turns out on the mixture screw. I'm almost tempted to leave it as it is and accept the occasional cough.
 
Carb is lean from the factory I would go with a 45 slow jet and a 165 or 170 for the main and you will be near what they had in 91 later years were leaner to meet epa requirements

Brian
 
I get an occasional cough from my 92 softail but not often if it is a regular occurrence then perhaps it would indicate a lean condition at low revs
next size up in slow jet may clear the condition however raising the slide needle with some washers under the seat may also add fuel at lower revs as would a larger main jet
All the jets supply fuel all the time the main jet is restricted from supplying too much fuel by the slide needle the needle is tapered so as the slide goes up there is less restriction on the main jet from the needle and so it supplies more fuel
Tuning the carb is a fine balance between the airflow and the fuel
I would start with a larger slow jet and see what happens

Brian
 
Definitely a low speed circuit issue. Fin has provided good information. The main thing to do when fine tuning a carb is to do one thing at a time, understand the results from that single change before trying something else. How does the motor react if the turn the A/F screw in all the way? All the way out? How the motor reacts to those conditions will tell you a lot about the pilot jet. Have you taken the carb apart to make sure all passages are open? Have you checked float level?

I have never had an issue with the carb on my all bore 107" motor running a CV44. The other day, I went to take her out for a ride; started quick as usual after sitting for a couple of weeks but farted, popped and would not idle; running nasty.:confused: Pulled the carb which was very clean inside, pulled the jets, blew everything out, checked float level, put the carb back on and she runs like a top with nary a stumble, cough, miss or pop. I still don't know what I blew out but think there was something in the pilot jet. When I first looked through it toward the light, I didn't see any light at the end of the tunnel but never saw anything come out.

Point is that I think it important that you know you are working with a carb that is not hindered by anything internal; a baseline. If you know that the baseline is good then you know that the setup needs to be tweaked.;)
 
I got the next size up main jet too. Should I hold off on that one until I get the low speed sorted?
My plan is to install the new pilot jet, turn the mixture screw back to about 1 3/4 turns and start from there.
 
Only make 1 change at a time then if it gets worse you will know where to backtrack to and if it is better you havent gone too far and made it worse

Brian
 
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