2016 KTM 150 SX Jetting HELP!!!

Sorry this is a long one. I have a 2016 KTM 150 SX and I hate jetting. The stock jetting is for 300-700m at +30C and I live at 500m and ride in +30C.... but the bike ran like crap. It comes stock with 45 pilot, air screw 1 turn out, 180 main, and NOZG needle in third clip. The bike would idle for 10 seconds before sputtering and wanting to die. 1/4 to 3/4 throttle was so boggy(lean), And IDK at all what's with the main but it has a bad bog at full throttle..... Yes, the bike is in perfect mechanical order as it's brand new, I'm running fresh gas with proper mix, everything is sealed, air filter is clean and nicely oiled. I'm certain it's the jetting. I have made it run a bit better by putting the clip at the fourth position. I have gone to a 40 pilot, air screw 3 turns out, and I have no idea if a 185 main helped but it's still terrible at full throttle. I have spooge going down my tailpipe after idling for a bit and when I take off after idling for 15 seconds it sputters a fair amount and I have to clear it out by going half throttle through some gears. But the thing that scares me is that I'm way off (especially the pilot) from MXA's jetting of this bike- 52 pilot, air screw 3 turns out, NOZE needle 4th clip, 190 main. IM SOO CONFUSED HELP. I have tried a 190 main but I'm back to a 185 because it was so gurgly, would surge and would rev very slowly I'm guessing it was rich. But it's still terrible at full throttle, it revs real slow. When I'm in first gear, clutch out and about to stall, then I whack it wide open it falls on it's face, but then after going full throttle for a bit then I close the throttle and quickly go 1/3 throttle it sputters then pulls HARD.... Ughhhhhh.... Sorry if this is hard to understand I'm long winded. ANY help would be GREATLY appreciated :). Yes I have followed Spanky's jetting guide etc but I just can't figure this out. Help :/

I'm on the verge of giving up and just buying a Lectron carb.:banghead:

Start at the bottom and get it idling well Google spanky's jetting guide and set the airscrew and pilot correctly and go from there , hit up Bushpig on these forums, he has a Suzuki needle in his bike the same as his 200 as I suggested to him

sounds like more than incorrect jetting.

check the reed valve, clean the air filter, and try a new spark plug

my 2016 stock with the same jetting was rich everywhere and fouling plugs and i'm at 150 meters

2 hours ago, kxkid110 said:

my 2016 stock with the same jetting was rich everywhere and fouling plugs and i'm at 150 meters

That's weird... My bike ran better at 4th clip position than 3rd and I have thinner air. Btw I have not fouled any plugs... I wonder if i have an air leak or something. I had a stripped air boot clamp to the carb but i got a new one(a bit too wide but it still works I think) and I think it runs different. I was messing around with the air screw and I was looking for the highest idle and I was about 2.5 turns out and I was revving it and it was sputtering but no smoke(it was warmed up though) and revved it pretty high and as it was revving down I think I heard it ping once. It sounds like it has a hanging idle but it sputters at idle and low throttle. What does pinging(pre-ignition) sound like? I'm running 91 octane pump gas in premix. Full throttle is slow still. It's just as fast as half throttle but actually revs slower but doesnt sputter. I dont get it. :cry:

2 hours ago, kxkid110 said:


Is there supposed to be gas in the boot in between the carb and the engine while it's off? Because I just loosened that clamp and gas came running down the carb... Halp :smashpc:

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