Still poppiing on decel

[CR2CRF]

Just did the Dave Mod, Uni Filter, smog removal, snorle gone. Yep. It is a whole new bike. Rips is a good word for it now.

Only thing, it still pops on deceleration. Any ideads? Also on the Dave mod, I ground down the carb tab not the screw tab. With the smog stuff out of the way it's so much easier to get to the fuel screw.

BTW fuel screw out 2 1/4 and I live in SoCal, maybe 1000ft. 55/160 on the pilot/main.

[BRP Chaos]

Mine pops some on decel but not as much. I run 100 to 3000' on average. It did improve after Daves mod and Smog removal. So is it improved or just as bad as before. I don't know if you ever get rid of it all.

[oilspot]

popping on deceleration is usually an intake or exhaust leak from what i've dealt with. More often intake

[Denn10]

first id try 2.5 out and see if that helps, stock exhaust or what??? popping on decel should have nothing to do with exhaust leak, its either and intake leak making in leaner or you may have to bump screw or possibly pilot but try screw. In is lean and out is rich so try 2.5 and see if it helps. Do you have a low idle or is it normal?

[Kenzo]

test ur pilot size per the "sticky" on the jetting page...most likely u need to go u one pilot size if u still have popping/burble on decel at 2 1/4 turns out...

?

P.S. i take that back...u shud be gud at 55/160 but still test it...

[oilspot]

first id try 2.5 out and see if that helps, stock exhaust or what??? popping on decel should have nothing to do with exhaust leak, its either and intake leak making in leaner or you may have to bump screw or possibly pilot but try screw. In is lean and out is rich so try 2.5 and see if it helps. Do you have a low idle or is it normal?

Actually exhaust leaks can cause popping on deceleration. oxygen entering the superheated exhaust can mix with any unburnt fuel and cause popping.

I forget the actual explanation on how this happens/ works. I had a popping on deceleration problem I was trying to fix on a go kart a while back. Turned out it was an exhaust leak.

[alarmin]

Popping on decel is usually a lean condition. I would try to go 1 size bigger on your pilot - IMHO:thumbsup:

[HeadTrauma]

+1 on the pilot. Try a size 58 and readjust the idle screw to suit.

[martinfan30]

Go to a 58 pilot and read this.

https://www.thumpertalk.com/forum/showthread.php?t=327405

[CR2CRF]

Well, It sure runs better. Thankfully it's only the jetting. Thats a quick fix.

[dezert thumper]

I also live in so cal. alot of us around here are running 58/170 I'am running a 58/168 but may go up to a 170 just because it mite help it to run a little cooler

[HeadTrauma]

Dang, you guys are running mains around 168-170? That's a whole lot of main jet.

[martinfan30]

Dang, you guys are running mains around 168-170? That's a whole lot of main jet.

That's too much main.

The L's like 158, maybe 160. Anything more and you need a t.charger!?

[Nick777]

what is a pilot?

[martinfan30]

what is a pilot?

A pilot is the jet that controls the slow speed circuit of the carb.

It is a small orifice that meters fuel into the engine at idle to about 1/4 throttle.

[HeadTrauma]

The L's like 158, maybe 160. Anything more and you need a t.charger!

That can be done. ?

[martinfan30]

That can be done.

Yeah buddy!

I just hope some people get over the little things and begin to re-contribute.?

[Horri]

Anyway..I agree with oilspot.Popping,,air leak.

[Kenzo]

Anyway..I agree with oilspot.Popping,,air leak.

not sure about the air leak but a 58 pilot wus way rich for me at sealevel with the supertrapp race exhaust & intake fully opened up...the fuel screw had zero effect(test it!)...168/170 main wud be super rich when i had the stock CV...160 wus plenty

there is no mention of an aftermarket exhaust on this application but make sure the header "gaskets" are gud and in place, bolts tight and maybe sum Hi-Temp RTV where the pipes connect after the header...

?

[Kenzo]

Yeah buddy!

I just hope some people get over the little things and begin to re-contribute.?

...someone get pissed-off???