Just finished my Dynojet install and the only problem I have is just a SMALL amount of decel popping. I'm still waiting for my Powerbomb header but have a FMF Q4 can on the stock header. Here's what I did...

128 Main Jet
Stock Pilot
F/S out 2.5 turns
Drilled the slide hole
E-clip on 3rd slot
No-airbox lid w/ K&N filter

It pulls nicely through all gears without any surging or hesitation at all. Idles perfect. Is the decel popping from the smog crap that is still on the bike? Or do I need to adjust the F/S just a bit. I think I'm really close...Is it possible that I nailed on the first run!!??

 

fuel mix isn't quite right - pretty sure most guys will say its a sign of running lean. couldn't help ya with how to correct it though. i'm not that familiar with carb tuning

 

with those settings it sounds like its the smog crap..... popping can be too rich also... i saw 12" flames shoot out of a hmf muffler on a klx in FL.... pretty sweet but a tad rich....

 

If you have done all the free mods (remove smog equip) then i would suggest setting your pilot screw at 3.5 turns out.I'm asuming you are sans the airbox lid.With a 128 main and stock pilot i'd recommend 3 1/2 turns out on the pilot screw.A #40 pilot jet is pointless unless you are going to a 300 kit.what is your elevation?the changes i listed above will work good from about 700-2000 foot elevation.

 

Yeah i'm a dunce.I missed that for some reason....you must remove your smog equip to eliminate your decel popping problem.

 

JS, also check and make sure you have a complete seal around the header to muffler pipe connection. Just the slightest leak will also cause the popping on decel. A little PermaTex Muffler & Tailpipe sealer usually does the trick!

 

You may never get rid of it, if it runs goodI wouldn't worry to much about it.

 

The only time my bike pops just a small amount is when I am coasting down the hill from work in an rpm that is creating some good back pressure, other than that its flawless. And its so slight that you have to really listen for it.

 

The first thing to go when you're in your forties is your hearing Deej!

 

I checked the plug after another test run today and found it to be running a rich. The end of the plug was black just about half way round. Could this be because of the stock header? The settings I used to jet are for a FULL exhaust. I'm still waiting on my Powerbomb! Would the header lean it out some?