125/150/250/300 KTM/HUS/GG jetting thread

FGR01 wrote:

Better hurry up.  Not going to be able to find many decent low hour ones for long.  I know people like the TBI 300's, but the...

Better hurry up.  Not going to be able to find many decent low hour ones for long.  I know people like the TBI 300's, but the TBI 125's are absolute dog poop compared to the carb bikes.

purplepowerband25 wrote:

I have a 2019 YZ144 with the Mikuni that I’ve done a lot of testing on for strictly riding moto, track is at about 400 ft...

I have a 2019 YZ144 with the Mikuni that I’ve done a lot of testing on for strictly riding moto, track is at about 400 ft and in South Texas. I know the mikuni’s between the YZ and SX are different but trying my jetting may help you with your Mikuni. My bike has an Athena 144, VForce 4, vortex ECU 

Jetting:

Main: 460

Pilot: 40 (any leaner and I feel like it it gives up some power down low but it does have a cleaner idle but I have my bike set up not to idle for best throttle response)

Slide: 4 cut to a 5.0

Jet needle: I’ve tried the S1, S4, s7, and S9 (kx125) currently running the S7 from the S4 and I’m really liking the midrange power from the S7. 
Needle: I have a ton of different needles that I’ve tried,  I have a standard needle from the 04 Kx125 6chj that I put in with the s9 nozzle and it rips but would have to really clear it out. 
Current set up is 42-74 clip 3 with the s7 and it’s pulls hard and has no hiccups, or hesisitation, no lean pops, or bog from 1/4-half throttle. 
Needles I haven’t tried with the S7 yet that I have are 43-74, 44-74, 42-75, 43-75, 24-74

A/S: 2-2.5 turns out 

AJ565 wrote:

The 460 main is way too lean on a KTM125. Those bikes like the fuel.

purplepowerband25 wrote:

I have a 2019 YZ144 with the Mikuni that I’ve done a lot of testing on for strictly riding moto, track is at about 400 ft...

I have a 2019 YZ144 with the Mikuni that I’ve done a lot of testing on for strictly riding moto, track is at about 400 ft and in South Texas. I know the mikuni’s between the YZ and SX are different but trying my jetting may help you with your Mikuni. My bike has an Athena 144, VForce 4, vortex ECU 

Jetting:

Main: 460

Pilot: 40 (any leaner and I feel like it it gives up some power down low but it does have a cleaner idle but I have my bike set up not to idle for best throttle response)

Slide: 4 cut to a 5.0

Jet needle: I’ve tried the S1, S4, s7, and S9 (kx125) currently running the S7 from the S4 and I’m really liking the midrange power from the S7. 
Needle: I have a ton of different needles that I’ve tried,  I have a standard needle from the 04 Kx125 6chj that I put in with the s9 nozzle and it rips but would have to really clear it out. 
Current set up is 42-74 clip 3 with the s7 and it’s pulls hard and has no hiccups, or hesisitation, no lean pops, or bog from 1/4-half throttle. 
Needles I haven’t tried with the S7 yet that I have are 43-74, 44-74, 42-75, 43-75, 24-74

A/S: 2-2.5 turns out 

AJ565 wrote:

The 460 main is way too lean on a KTM125. Those bikes like the fuel.

purplepowerband25 wrote:

Ive ran up to a 480 on my YZ, but took away some over rev. So 460 for summer and 470-480 in the winter. 

AJ565 wrote:

The 460 main is way too lean on a KTM125. Those bikes like the fuel.

purplepowerband25 wrote:

Ive ran up to a 480 on my YZ, but took away some over rev. So 460 for summer and 470-480 in the winter. 

purplepowerband25 wrote:

Also running a richer jet needle s7 (s9 being the richest) you may be able to get away with a leaner main. 420-430 I think is...

Also running a richer jet needle s7 (s9 being the richest) you may be able to get away with a leaner main. 420-430 I think is STD main for the YZ.