Backfire through carb.

[SlyJJ]

Ok, since I've gotten the points setup properly done and installed it seemed like everything was going to be on the up and up but my bike will not idle without the choke- at least it didn't. Now it wont even idle at all (!). Since one of the carb manifold gaskets was damaged I figured the coughing through the carb was caused by a lean condition. I'm fouling plugs left and right here and this bike cant make up its fucking mind. After FIXING what could have only been a problem and then reinstalling the carb, the situation has worsened, wtf?

The points are timed in, and the coughing through the carb suggests an intake leak somewhere but I fixed any possible culprit with a new set of gaskets and torqued her down. These were brand new jets I installed into the super b, and I squirt carb cleaner through the pilot and main jets prior to install (twice). Could this be timing related? Should I retard the timing a hair? I'm not really sure where to go. It was running and idling earlier today and now its a bag of shit all over again not wanting to stay running without full choke and a semi open throttle.

[Tattooo]

Yes timing is off.... and it's a carb problem also... Is your carb clean??

[SlyJJ]

Yes timing is off.... and it's a carb problem also... Is your carb clean??

I've cleaned my carb thoroughly, and once again this morning just to eliminate that as a possible issue. As I slowly advanced the timing I was able to get it to idle as it would warm up a bit but she still required JUST the slightest bit of choke. I mean, going off of what I know from carbs that would suggest a lean condition but I've got a 33 pilot in there and the plugs are becoming quite dark to the point I'm afraid I'm going to foul yet another set. To top it off, it would seem the problems improve as the engine heats up rather than get worse- also suggesting I should try a size up jet, but 33 is the upper range I've seen advocated on nightrider website for engines this size- am I wrong on this and am I just dumping excess fuel into the bike?

[Shanebeee]

Going through the same thing, Had a small intake leak, so put new seals, (all 3) and had a bent needle so put in the 88 Sporty needle just to rule out any leanness. Now same thing won't run without choke and coughs out the carb and backfires at high rpm. Talked to a few mechanics and they suggest Seals weren't installed correctly. Have to take it apart and reasssemble today. Assuming my timings not off seeing that it ran before i "fixed it" haha. If it aint broke, fix it till it is

[MegaDON666]

How is your advance unit?
Similar issue on my Ironhead, went thru the carb, changed out condenser and points. Checked for intake leaks. Ended up being my advance was wore out.

[SlyJJ]

Quick update, turns out the carb is hanging in at a weird angle which doesn't allow the float bowl to sit properly. This explains why I couldn't get it to run without choke and would get constant lean symptoms despite having a rich pilot- it never got a chance to even try it.