Hi everyone,

I've been a member of this forum for 4-years and I have spent a lot of time lurking / finding valuable information so I just like to say thank you! My flavor is single-track, off-road riding and my previous bikes were all KTMs. I bought the klx mostly because I wanted something I could use for local commuting as well as trail riding. Plus, it was far less expensive compared to a new KTM.

Upgrades:
Renthals, Honda bend cut to 30"
Moose hand guards
Zeta front break & clutch levers
MSR skid plate
Wide foot pegs
EBC-R brake pads
47-tooth JT aluminum rear sprocket
No-toil dual element air filter
Full Moto-Pro suspension & springs including Ultra Max fork valves

I was running the stock CVK carburetor with the Dynojet Stage-2 kit and I recently purchased a TM 33/34 Mikuni pumper from Bill Blue plus, an FMF Q4. I was really struggling riding tight, technical single track with the lack of low-end grunt and the new pumper is much better! I almost have the jetting sorted out; the bike starts good, idles well, accelerates great to 8,500 RPM then I get a hesitation / surge to 9,500 RPM. Currently, I'm running a 40 Pilot, 145 Main, Needle clip in middle (3rd) position, Fuel screw 1.5 turns out and snorkel removed. I'm also roughly 700' above sea-level. My spark plug reading appears grey to slightly tan so I think I'm still slightly lean on the Main..? Any thoughts? I do have a 147 Main that I could try but I have not read of anyone else running this rich of a main jet.. Thanks guys for any thoughts you man offer..

Here's my bike: https://www.youtube.com/channel/UCVm...hReaQOJmriGOdQ

 

There's no danger of hurting anything by going 1 step richer on the main. If you already have one and don't mind the work, I'd say slap her in there and let us know if it made a difference. Just my 2 pennies.

 

Welcome to the forum.

My evaluation of jetting using plug color is no longer valid with the current fuel situation.

 

I spoke to Bill Blue last week and he helped me determine that I was going in the wrong direction on the main jet.. I reinstalled the 137.5 Main with the 40 Pilot and it's now running well in all aspects! It also starts easy without needing to be choked. It still might be a little rich and I could possibly step down to a 135 Main however, I'll evaluate it further and ride it as is..

Bill originally shipped the Mikuni to me with a 37.5 Pilot & 137.5 Main, which the motor bogged when I whacked the throttle off idle. I knew this was a lean condition (lots of air & not enough fuel) and I now know that this is a pilot lean condition only..

 

Great info.. I'm pretty sure your in for another big surprise if you'll pull that lid and rejet for that increase in airflow.. If it is a little rich up top now, your surprise is only a lid-pull away!