changed air filter now it pops

[jrod23ram]

I have changed my air filter to a bigger air filter and now it pops on deceleration. My valves are in tolerence and it has never done this before I changed the filter. Would a bigger main jet work or would it be the idle jet being that it only does it on decel.

[Grath]

Try adjusting your fuel screw or moving up to a bigger pilot jet.

[Joshz400_03]

You can't just change part of the intake and expect it to run the same. Go up on your pilot jet 1 size and try that.

[zookie400]

some popping on decel is normal with modified intake and exhaust, so adjust your jetting for idle/running, NOT decel.

if there is excessive popping in the exhaust, a lean pilot circuit is the cause. if it is idling strong, and doesnt hang in high rpms after you blip the throttle, i wouldnt touch the jetting.

on decel from high revs, the engine has a much stronger vacuum signal than normal, which throws the pilot circuit A/F ratio toward the lean side. once the engine is at low rpms the vac signal is where the jetting was set for and the pilot circuit works as intended. the vacuum signal shift is usually amplified with intake and exhaust mods.

[jrod23ram]

Thank you all for the quick response. I will try the pilot jet first. It used to pop a little but now it has gotten extreme.

[spize909]

just open up your fuel screw some.....same as going to a bigger pilot.

[1955gasser]

For some reason, I like my Poping on deceleration, i think it sounds cool.

[jrod23ram]

Originally Posted by spize909

just open up your fuel screw some.....same as going to a bigger pilot.

how much is some?

[Mikeb3119]

try half a turn each time until it stops

[zookie400]

dont adjust the fuel screw to fix the popping. adjust the fuel screw the proper way (engine running at idle, turn it in until you get the highest rpms....i think there is a sticky on it if you havent done it before.) and leave it regardless of the popping.

would you rather have it foul plugs and have bad off idle throttle response with a hanging idle and no pop on decel? or would you rather have it run mint with a pop on decel?

[jrod23ram]

It did idle little lower when i went to the bigger filter. then i just bumped up the idle a little. I ordered a pilot jet first, then if it is way out of wack then I will just dea with the poping. It is just the popping is so loud and annoying.

[fastfarmer]

New filter increased air flow..At WOT is the main circut and pops on decel cause its lean on high RPM's..bump main jet a couple of sizes. Pilot is start to a 1/4 throttle..doesnt do nothin on WOT leave fuel screw alone till ya bump up main jet.. put new plug in run through gears, at WOT cut it off and pull plug..if its greyish or tanish its good..black is rich..white ,still looks new = LEAN...my 2 cents

[zookie400]

Originally Posted by fastfarmer

New filter increased air flow..At WOT is the main circut and pops on decel cause its lean on high RPM's..bump main jet a couple of sizes. Pilot is start to a 1/4 throttle..doesnt do nothin on WOT leave fuel screw alone till ya bump up main jet.. put new plug in run through gears, at WOT cut it off and pull plug..if its greyish or tanish its good..black is rich..white ,still looks new = LEAN...my 2 cents

decel is throttle closed, which is the pilot circuit regardless of how fast the engine is spinning.

and like i keep saying, dont tune your jetting based on what it does during decel, unless you are only going to be engine braking down the worlds longest hill every time you ride.

[spize909]

pilot circuit..........
Zookie, there is such a thing as too much popping. I've experienced it on my wife's quad. Tuned her fuel screw correctly and it's minimzed a great deal but not gone.

How many turns is your screw open now?
Try tuning the fuel screw exactly how it is described in the sticky.

[zookie400]

too much popping...... like a legends car coming into the corner?