125-200cc 125 / 150 Jetting Database

2009 WR144

Carb = TMXx 38
Pipe & Silencer = FMF Fatty / TurbineCore 2
Other engine mods = 0.3 Base Gasket, Walt's PV grind, PowerNow divider
Premix ratio & fuel type = Spectro Platinum SX syn, 40:1, 93 pump gas
Temperature range (deg F) = ~50 - 70F
Elevation (feet) = ~130 - 580ft
Main jet = 470
Pilot jet = 35
Needle = 6CHY16-62
Clip position = 3
Air screw setting = 1.75
Slide = 5.0
Plug = BR8EG

Conclusions/Results:

First day of testing (580ft) was wet and cool, woods ride with two long straights. Bike didn't need the choke to start cold (air screw 1.5 turns out) but ran very good from bottom up onto the pipe. Had an issue on the straights shifting right as it was climbing on the pipe and giving more gas. Slight blubber that would clear if I let off the throttle a bit. Overall, bike ran great everywhere else, just a little fine tuning for those open rips.

Second day of testing (130ft), dry and about 70F. Ran the air screw out another 0.25 turn, bike needed a little choke on cold start this time. Lots of long, open sweepers to get out to a tight, sandy MX-style woods track. Same issue when climbing on the pipe on the straights, slight hesitation but VERY slight. Bike ran fantastic all day but did have some spooge at the pipe/silence joint and tip. Going to try the needle a clip leaner and see how it goes.

Very impressed with this little smoker, it grunted up hills without issue, LOTS of power when it hits and still smooth in 3rd gear while riding the semi-tighter stuff. Have to check my gearing, rear I swapped to a 50T, front CS I'm blanking on, either 12 or 13.

2009 CR125
STOCK PIPE/SILENCER
38MM TMXX
STOCK MOTOR
MOBIL 1 SYN. PREMIX 30:1
4100-4800FT ELEVATION
40-75*F
MAIN- 450
6CHY16-62 NEEDLE 4TH CLIP
37.5 PILOT
5.0 SLIDE
BR9?? PLATINUM STOCK PLUG

FIRST TIME AT THIS ELEVATION, TYPICALLY AT 0-1000FT. HONEY LAKE MX IN CALIFORNIA, steepest longest uphill ive ever seen on a track, no room for error on the main jet in these conditions. Started on friday with 65*, 40 pilot and 460 main. Went down to the 37.5 pilot and was better on the bottom. Tried the 3rd clip on the needle, total fail. Back to 4th clip. I was struggling on the long uphill but was nervous about dropping the main due to the huge loads this track was putting on the bike. Saturday, temps where quickly going above 70*f, dropped the main to 450 and picked up a whole gear on the uphill. DRASTIC improvement. Left it there rest of the weekend, temps dropped to 45-50* on sunday and i gained 5-10mph on the uphill and was able to carry 3rd gear on turns i had to run 2nd the day before. Ran from 1.75 to 2.5 turns on the air screw depending on temp all weekend. In hindsight i would have tried 3rd clip with a half clip washer on saturday if i wasnt running motos all day. 440 main may have been a smart choice as well but i made a 9 hour trip for this race and it would have been a shame to stick a ring. In all the bike ripped, but was destroyed on the long uphill start and long climbs by the 250's and 450's. Bike never cleaned up on the starting gate all weekend, had a blubber on the bottom every start until i hit the 5-6th turn, sometimes half a lap. I cant tell if its jetting or plug fouling issues from warming the motor up for a few minutes after i see the white flag. Need to fix it though because it was a dog off the gate. No regrets though, i had a great time running the only 125 i saw all weekend

2009 WR144

Carb = TMXX 38
Pipe & Silencer = FMF Fatty / TurbineCore 2
Other engine mods = 0.3 Base Gasket, Walt's PV grind, PowerNow divider, iBooster
Premix ratio & fuel type = Spectro Platinum SX syn, 40:1, 93 pump gas
Temperature range (deg F) = ~80F, humid
Elevation (feet) = ~800ft
Main jet = 460
Pilot jet = 32.5
Needle = 6CHY17-62
Clip position = 3
Air screw setting = 1.5
Slide = 5.0
Plug = BR8EG

Conclusions/Results:

Hair leaner settings from my last test session (MJ -1 step, PJ -1/2 step, Needle -1/2 step), feels more crisp and the air screw wasn't vague on either side of 1.5TO. Choke was still barely needed, bike fired quick and clean, revs from idle to WOT on the stand were strong and smooth. Super humid out in the 80's, lots of stop and go trail work with long idle sessions. Bike was happy for the ~2hrs I was in the woods, refired easier when hot than two test sessions ago. Once speeds resumed and pace picked up the power always felt on tap, no pronounced bog (but that soft trans is still there), no sputtering although the pipe joint still drooled quite a bit. Overall I was real happy leaned out a bit from my last ride. Rocky hill climbs were effortless, no bog, just smooth power. (BTW, my new Motoz Tractionator Enduro S/T's are freekin' badass!! wow. Thanks, Kelly!)

Since this test session I've repacked the silencer, zip-tied the pipe joint grommet and cleaned the air filter. Tests on the stand and around the yard felt very crisp, temps still high but less humidity. Bike was pulling the front wheel from idle/slow rolling with ease. Think the filter was pretty dirty/oily for that last test.

Hope to get back out on my local loop for some more trail work and testing this weekend. Same conditions and terrain so good back-to-back.

Oh, and I love this freekin' little bike! Featherweight muscling it around as I was burning in an old trail. Total giggles...

Year & Bike Model = '09 WR125
Carb = Mik (stock)
Pipe & Silencer = Stock/ stock arrow
Other engine mods = 0...rock stock inlc. air filter.
Premix ratio & fuel type = 40:1 putoline
Temperature range (deg c) = 10-28
Elevation (feet) = 1500
Main jet = 480
Pilot jet = 35
Needle = factory needle
Clip position = #4
Air screw setting = 1.5 - 1.75 out
Slide = 4.0

Runs very well and has a nice safe over rev! don't know what all this pwk conversion is about no need i say NO NEED! The bike rips and handles and stops, perfect......................

Year & Bike Model = 2011 WR150

Carb = 36mm Keihin PWK A/S from 2011 KTM 150XC

Pipe & Silencer = Stock pipe / FMF S/A silencer

Other engine mods = Exhaust spirngs Stock / silver.

Premix ratio & fuel type = Maxima K2 @ 40:1, 100LL AvGas / 110 Sunoco race gas mixed 4 gal AvGas to1 gal Race Gas. Non Ethanol Gas is no longer available in Mississippi and may not be anywhere according to the Gas Distributor.

Temperature range (deg F) = 65

Elevation (feet) = 300ft. to 1,700ft ASL

Main jet = 175 (got rid of a throttle bog after needle change)

Pilot jet = 35

Needle = NOZH (NOZI stock) (slightly richer needle so I could run on #3 position and keep more needle in needle jet.

Clip position = #3 NOZH richer than stock NOZI #3

Air screw setting = 2 3/4 - 3

Slide = 6.0 (stock 7.0)

CHECK YOUR FLOAT SETTINGS. Mine was too high and overflowing when you hit bumps or slightly leaned the bike over.

All bogs now gone. 21mpg.

Year & Bike Model = 2009 cr 144
Carb =38 tmxx
Pipe & Silencer =fmf fatty and tc
Other engine mods = power valve clearance Premix ratio & fuel type =35-1 motul & 99 RON mix. Mixture of 91PON and 106PON.
Temperature range (deg F) = 85-90 at this time.
Elevation (feet) =3000 ft.
Main jet =450
Pilot jet =35
Needle =CHY16-62 2004 rm125 needle.
Clip position =#1 leanest setting
Air screw setting =2
Slide =4.0
Conclusions/Results = THIS THING RIPS !!! (comparing it to my 2001 Honda CR250r) I went the PWK route because I had a bog with the tmxx, no let me put it this way, I experienced Complete Lack Of Any Internal Combustion at 1/3 thru 2/3rd throttle in the midrange. Now I know what a bird hears when flying. With the pwk I was never able to tune out the C.LO.A.I.C. with the supplied jets but was able to minimize it (still sucks). Then I read the JD jets are too lean for some engines. Also didn't like the loss of top end. Found a thread by dartty- sorry can't remember all his call sign, I'm sorry mister, and I mean that because you have saved the day! I can wack the throttle open at ludricously slow speeds and go ripping off into space. Excellent response every where. Makes torque in the midrange which helps in power sliding almost as well as the 250 honda! Runs really well but my plug is black after ripping around at half throttle and up. Would a leaner slide help there? I have no complaints with the bottom range. I know that dartty has a 125 and settled on the 16-62 and 5 slide. How much of a difference is a 63? 64? Yeah I started out at clip #2 thinking with the 4 slide it might not run too well. Had a low booming exhaust note and ripped. Went to leanest position (sounded better) and picked up even more torque in the mid. I think my main is too big, still revs high though. Maybe it can rev higher? The 16-62 needle lets more fuel past the main? I'm mixing race fuel that is now $6.79 a gallon to abide by Husqvarna's 98 RON fuel requirement and I see individuals here running 92 PON ( which is approx 96RON) and claiming no ill effects. Anyone have an opinion on this?

'11 CR150
TMX(radial slide)
RB Designs, bore to 39mm, plate, air screw, low speed mods
480 main
17/62 RM needle 3rd position
35 pilot
1.5 air crew
FMF pipe/stock silencer... MX riding

morning started out around 37 degrees and ended up around 75... 1200ft elevation

Awesome running, pulls great, no hesitation or spooge.... love this set up....

2007 wr125 with 2002 cr125 motor and ignition.
old style tmx38
370 main
25 pilot
modified slide
60 needle
carb divider (custom).
kx125 exhaust pro cicuit.
wr muffler
airscrew 1.75
no base gasket.
20-40 degrees celsius 500 ft.

runs well, no bog, good bottom and mid, screaming top.
only struggles when i do.

Year & Bike Model =2009 Wr144
Carb =Mikuni TMX
Pipe & Silencer =FMF Fatty Gold/ FMF Shorty
Other engine mods = Twin Air & CR Ignition
Premix ratio & fuel type = Klotz Super Techniplate @ 40:1 - Sunoco 93
Temperature range (deg F) = 40F-80F degrees
Elevation (feet) =700'-1600'
Main jet = 470 cold or 480 hot
Pilot jet =35
Needle = 15-74 Needle from power up kit
Clip position = 4th down
Air screw setting = 1.5-1.75
Slide = 4.0
Conclusions/Results = Runs strong pulls hard on top but has an occasional bog maybe powervalve linkage slop, did adjust slop out waiting to test this weekend

Check your float level.

Will do, what is the actual measurement for the float level??

I believe I heard 8mm for the Mikuni

Bike= 2012 WR125/144
Carb= Mikuni with RB carb mods... divider plate, bore to 39mm, low circuit mod, thumb screw
Pipe & silencer= stock
Other engine mods= .4 base gasket
Premix ratio & fuel type= 40:1 Bel-ray & premium pump gas
Temp range (deg F)= 35 to 65
Elevation= just above sea level
Gearing= stock front / 52 rear
Slide= 5.0 slide (RB)
Main jet= 460
Pilot jet= 35
Needle= 6CHY16-62 (2004 RM125 stock)
Clip position= middle
Air screw= 1 1/2
Power Valve adjustment= 3/4 to top
Power Valve spring kit= stock/silver springs

I just wanted to update this post since my 144 install. Left same jetting as when a 125. Bike flat out rips. Runs clean and strong from bottom to top.

Year & Bike Model = 2011 WR150 with Uptite Husqvarna 167cc kit.

Carb = 36mm Keihin PWK A/S from 2011 KTM 150XC

Pipe & Silencer = FMF Fatty WR125 pipe / FMF S/A silencer (going to try a modified FMF KTM 2003-04 SX200 pipe)

Other engine mods = Exhaust spirngs Stock / silver.

Premix ratio & fuel type = Maxima K2 @ 40:1, 100LL AvGas / 110 Sunoco race gas mixed 4 gal AvGas to1 gal Race Gas.

Temperature range (deg F) = 65

Elevation (feet) = 300ft. to 1,700ft ASL

Main jet = 170 (144cc = 175)

Pilot jet = 35

Needle = NOZH (NOZI stock) (slightly richer needle so I could run on #3 position and keep more needle in needle jet.

Clip position = #3 NOZH richer than stock NOZI #3

Air screw setting = 3 (144cc = 2 3/4)

Slide = 6.0 (stock 7.0)

CHECK YOUR FLOAT SETTINGS. Mine was too high and overflowing when you hit bumps or slightly leaned the bike over. Set Keihin at 14mm

No bogs now gone. 21mpg.

Gearing 14T / 50T Parts Unlimited Xring Chain.

Have you tried to use any of the Rm 125 needles . I would see if the Tmxx came on anything else that was closer in displacement also . Iam running the Suzuki Pwk needles from a 250 in my 167

Year & Bike Model = 2006 Cr125 w/2008 144 Cylinder
Carb = '06 TMX38 old style
Pipe & Silencer = FMF Fatty + FMF S/A
Other engine mods = 2008 144 Cylinder
Premix ratio & fuel type = 32:1 Maxima Castor 927 + Pump premium
Temperature range (deg F) = 40 - 110F
Elevation (feet) = 100 - 3700
Main jet = 400
Pilot jet = 35
Needle = 6DJ8-60
Clip position = 3rd
Air screw setting = 1.5 turns
Slide = 3.0
Conclusions/Results = Stutters and breaks up when hard on the throttle, raising the needle all the way helps a bit.
A week later 02/19/12- Went to a 30 pilot runs well up to 1/4 throttle, starts 1st kick. 1/4 throttle up make a "crackling" sound when hard on the gas. Eric Gore literature describes this as too rich. Raising the needle moves the "crackling" higher into the rev band. My thought now is to go to a leaner nozzle (needle jet as opposed to a jet needle), because this is the leanest needle that Husky lists. Anybody know of a leaner needle than 6DJ8-60?

Year & Bike Model = 2004 CR125 with FBF 135 cyl
Carb = TMX38
Pipe & Silencer = PC and shorty silencer
Other engine mods = none
Gearing = 13/50
Premix ratio & fuel type = 40/1 Spectro syn 1/3 powermist T111 and 2/3 pump
Temperature range (deg F) = 45-80
Elevation (feet) = S/L to 1000ft
Main jet = 380 (was 390)
Pilot jet = 32.5
Needle = 60 stock
Clip position = 2nd from top (was middle)
Air screw setting = 2-2.5
Slide = 3.0
Conclusions/Results =[/quote]

Bike rips. Still a little TMX burble just off idle. Bike took a while to clean out with the 390 main and burbled into the mid with the richer middle needle position. Now anything off idle the bike pulls hard for a tiddler. Top Eed seems a little weaker now but that maybe because I now have a little mid to go with the top.

Runs great in the woods but I do not know if I'd want to hold it WFO in the sand all day....may want a 390 main for that.

Year & Bike Model =2010 wr144
Carb =tmxx stock other than 2 small holes drilled in the float bowl drain bolt to keep fuel around the main jet.
Pipe & Silencer =stock
Other engine mods =dual fuel pet-cocks,twin-air filter,power-valve arm 3/4 up in slot-slight tension on power-valves
Gearing =13-53
Premix ratio & fuel type =32:1 motul 7102t,94 octane non-ethanol pump gas
Temperature range (deg F) =60-70
Elevation (feet) =100-2500
Main jet =460
Pilot jet =25
Needle =6dey 15-74
Clip position =2nd from top
Air screw setting =1.5 turns out
Slide =#4
Conclusions/Results =This is the setting that works best for me. I tried the rm chy16-62 needle with the #5 slide in many different clip positions and with various different pilot jets and main jets and could never get it perfect-it would be good in one area and too rich or lean in another. I also tried the 6dey 15-74 needle with several different pilots and mains and also with the #5 slide. I wanted to try all combinations to see how good I could get it.The #5 slide with the 6dey15-74 needle, 2nd clip position,25 pilot and 460 main ran really crisp with no spooge and a light brown plug reading but felt a little weak in the mid-range and the plug showed what I felt. I put in the #4 slide with-out changing any-thing else from my previous settings and the bike came alive-strong crisp power,no bogs and a dark brown plug reading. I do get some spooge at the silencer opening but it is after a lot of slow speed running in steep terrain and I can live with a little drooling to have it run like it does now. I also checked my float level and set it to 8mm and made sure that both floats were level with each other before I did any jetting on this bike.(my float level was 2mm too high and the floats were not level with each other from the factory)