backfire through crab

[txdunerider]

backfire through carb

Alright guys need some help here.........

At idle it pops through the carb.....

Checked the intake boot no cracks everything is good
rebuilt the carb completely ..again .. still pops
checked valves everything is good and within tolerance adjusted them anyways to get them back closer to specs. :argh::argh::argh:

any suggestions on what to check?

 

[WarriorRider80]

I had the same problem when i first bought mine. Did the same things you did then i tried turning my A/F screw out 1/4 turn at a time, ended up turning it out 1 full turn by the time i was done and it seemed to help. now it only does it maybe once every hour or so if im riding all day.

 

[txdunerider]

Mine does it from the moment you start it and if your not wide open it starts doing it. I checked every jet inside the carb cleaned everything cleaner and better than it was when it was new lol

 

[Gen1Pat]

Backfire through carb is lean, backfire through exhaust is rich. Turn the fuel screw out.

 

[txdunerider]

I will check it again I think I am 2 1/4 out right now, maybe go up on the primary again?

 

[Gen1Pat]

2.5 is stock setting for 2nd gen I believe. You may have to go up on the pilot. What size is in there now, and do you have any exhaust/intake work?

 

[txdunerider]

full older DG system (RCM), custom intake no air box (its a dune only toy) I will double check jet size again hopefully tonight , I worked on it on friday and just have not had a chance to get into it again since then.

 

[txdunerider]

I do believe it is a 45 if I remember correctly , but it has ran perfect for the last 2 years with this set up and it just started after it sat for a few and I redid the carb.

 

[WarriorRider80]

my fuel screw is 3 1/4 turns out, seems to help. I guess i could go up in main but it runs good and the popping stopped

 

[WarriorNewbie]

If u r 2.25 turns out and it still pops: turn it out more. Pat really seems to know his way around a motor

 

[Gen1Pat]

my fuel screw is 3 1/4 turns out, seems to help. I guess i could go up in main but it runs good and the popping stopped

If you are that far out on the pilot screw, you should be increasing your pilot jet one size.

 

[Gen1Pat]

I will check it again I think I am 2 1/4 out right now, maybe go up on the primary again?

I do believe it is a 45 if I remember correctly , but it has ran perfect for the last 2 years with this set up and it just started after it sat for a few and I redid the carb.

45 sounds a little small to me with that system and no air box. Hell I'm running a 52.5 with a slip on and Weston's intake. Could be that the pilot jet passageway is still clogged some.

 

[Gus]

If your crab is backfiring you might want to take him to a vet.

 

[WarriorRider80]

thanks Pat, i'll look into it, i figured i was getting pretty far out but like i said its running strong so....but yeah i'll def take a look at it

 

[lbjamm]

"backfire through crab"

Mine is backfiring through the lobster...

 

[buzzy613]

lmao!!! like pat said try a 52.5 if that doesnt solve it run a 55 at 2 turns and slowly turn it in (leaner) till the rich bog sices to exist

 

[Gen1Pat]

Well I wouldn't just jump right up to the 52.5. I'd go for a 47.5 first, but on a hunch I'm thinking a 50 will do it.

 

[PHANTOMLORD]

So i understand,, wich jet are you guys talking about??

 

[lbjamm]

The pilot jet. You know, in the cockpit. lol. Seriously, it is the pilot jet.

 

[WarriorNewbie]

If your crab is backfiring you might want to take him to a vet.[/QUOTE]

:haha: hilarious. He's a goner. Just boil him and melt some butter!