Been having trouble getting my Super E tuned on my 75 FXE. While riding, it's running super rich, backfiring out the pipes when off throttle. The exhaust is actually turning parts behind it black.

Problem is, if I lean out the carb even a touch more, the bike dies, as if it's too lean at idle.

I just did a basic rebuild on this guy. Seals, BBs, etc. Cleaned everything throughout. My thoughts was that maybe some trash got into it, which I have confirmed the bowl was full of crud already. Maybe I should put a real fuel filter on it...lol. (doing it right now).

So while checking over the carb again, I noticed that I can see light all the way around the throttle plate. I thought these were supposed to seal completely when the throttle was closed? Thinking this may be my "lean at idle" issue.

If it is supposed to completely seal, is it likely my throttle plate is warped or worn? Or is it the carb body?

Editing to add that I've checked for intake leaks. And I did make sure to back the idle adjustment all the way out when I checked.

Thanks!

 

My guess is your float is set too hi and drowning it and the ratio of idle mix and dial speed is off because of that pull the bowl and turn it upside wan and send a picture to the question

 

I thought the same thing but it's actually a smidge low

 

Verify that the new needle and seat are actually shutting off the fuel flow when the float is raised.

 

Definitely worth double checking, thanks!

I was able to find some trash in the intermediate, which could also account for the issue I'm having, but it was just a tiny dot partially plugging one of the holes in the side.

The float level is between 3/16" and 1/4" so it's a tad low but I'll likely leave it alone as to not complicate things further. It's hard to tell in the pic but my rule was just shy of contacting the float (not enough hands).

Definitely a lot of trash in the bowl for only running 30 miles since the rebuild. I got a K&N inline glass filter that I'll mount right at the petcock. I'm afraid if I run it near the jugs it'll vapor lock.

I pulled the throttle plate and reseated it, definitely sealing better than it was before. I can still see a bit of light through the edges but no giant gaps like I had before. Should've posted a pic of how crooked it was on the shaft. It's gonna always be slightly cracked open anyway by the throttle screw so seeing light past it isn't a big deal I suppose, just as long as it's centered in the bore.

 

With Any Inline filter...All Bets are Off... the petcock screen is All one Needs...anything else is like *****...Gonna cause Problems!!!

 

Had the same issue with the Holley on my C3 Stingray, made such a difference once seated correctly!

 

What size jets are you running? Mine are:
Main Jet: 70
Intermediate: 28
Runs perfect!