Spit’n and Pop’n

Folks, I’m new to the forum. I’m looking for some insight. I have a carb’d 05 FXST that just recently started spitting and popping and back fire while downshifting also if I run it about half choked it seems to run better. I have had it for 4 months and it has run fine until I put some Exxon 92 while on a run. When I choke the carb it stops acting up but runs at high idle. Has anyone ever had this happen to them? What could it be. I was thinking about idle mixture or intake leak. Thanks for reading.

Could Be A Leak, But You Didn't Mention Your Set Up, Pipes, Ac, That's All A Factor With A Spit,caugh.

As far as I know the bike setup is all stock. Who ever had it before me cut the baffles out but it wasn’t acting up when I bought it. I have put just over 2k on the bike since I got it.

spit cough

If you have to enrich the mixture with the enricher, you are way lean. Air filter restriction, float setting, bad fuel pump are A few. You could have a clogged primary jet or idle jet. SInce it happened after you added fuel, i suspect something got into a jet. First verufy the pump works. Un hook the fuel supply line at carb, put a vacumn pump on the vacum line in back. Pump it dpown, fuel shoudl run non stop. if not, fix the pump adn filter.

if that is ok, drop the fuel bowl, and remove the idle jet clean , spray cleaner into the idle circuit and ais bleeds behind the air filter, and try

Beaver

2003 Dyna Lowryder

Thanks all, I will be checking all this on the weekend, I will be putting new shotguns and some chrome on Saturday. I’ll post the results. I was figuring that it might be intake seals or the jets plugged. I got to pull the carb anyway and put in the new mixture screw.

mixture screw

I was sneaky enough to install the EZ mixture screw with the carb on. I used a angle grinder with a .125 short bit, drilled the plug, pulled it with a self taper screw adn installed the ez adjuster. Make sure you have the correct sequence of oring, with a drop of lube, flat washer on the bottm. The washer holds the oring in place as a seal in the circuit to the needle valve

beaver

still runs like crap

Ok, folks… I put on my new pipes and trany cover and cam cover on this past Saturday while I had that side off I installed the EZ mixture screw and a new manifold seal. I’m still having a missing and spitting problem. I have turned out the mixture screw all the way to 3 turns and makes no difference. What the bike is exactly doing is at 30mph in 3rd gear it misses and backfires through the carb, acceleration and running 65 – 70 mph isn’t an issue. Just low speed and while down shifting to slow down. If I pull the enrichment out just until the idle changes it runs fine. I sprayed the manifold seals with carb and choke cleaner and there isn’t any change in the idle. I also pulled the bowl and checkes the low speed idle jet and it’s clear. Thoughts? Thanks!

It sounds like your slow jet is plugged . It is very small, so it doesn't take much to plug it up. Hope this helps. Take the slow jet out and check behind it.

Will do! Thanks.

Okay folks, I still have my delema. I replaced the intake seals, manifold seal and checked the idle jet and jet is stock and clear. I ran the bike with out the air cleaner and It still is popping and I noticed when I got on the throttle it was spitting raw fuel out of the carb. Don’t think that’s normal… At a certain RPM in 3rd gear and 4th gear it chugs like its misfiring and cough out of the carb. Any more ideas. I’m getting a D&M spike air cleaner and going to be replacing the plug wires this week.

the idle jet is a stock 45 and I replaced the mixture with a EZ mixture. it's turned out 1.5 turns.

could be the timing, that would cause misfire. that could mean a bad coil or ignition modual.

From what I understand timing is non adjustable.