250-500cc 250 / 300 / 360+ Jetting Database

Year & Bike Model = 2009 WR300
Carb = Keihin PWK 38
Gas/Mix = Chevron Premium/Klotz R50 @ 40:1
Pipe & Silencer = 'New' Pro Circuit Platinum 2/Type 296 silencer
Temperature range (deg F) = 55-65f
Elevation (feet) = 3700-4200
Main jet = 178
Pilot jet = 45
Needle = stock needle from 2000 Honda CR250. Dont know p/n
Clip position = #2
Air screw setting = 1.5 - 2
Slide = 7
Conclusions/Results = Only rode it once in the high dez and all circuits were rich. The needle probably being the worst culprit. Bike ran hard, did not spooge on the silencer and revved out decently, but it would have to clear out after any extended low speed riding and throttle response was suffering. Need to test at my usual ride spot at lower elevation, but that setup was quite rich at 4000' with mild temp and low humidity.

Year & Bike Model = '09 WR300
Carb = Keihin PWK 38 AS
Pipe & Silencer = Stock 300 pipe, FMF Turbine Core II silencer with spark arrestor
Other engine mods = none
Premix ratio & fuel type = 40:1 91 or 93 octane
Temperature range (deg F) = 55-75F
Elevation (feet) = 5100 - 9000+
Main jet = 162
Pilot jet = 45
Needle = JD Red
Clip position = 2 (from top)
Air screw setting =1.75 out
Slide = 7
Plug = BR8EIX (Iridium)
Conclusions/Results = This is my first 2-stroke, so I'm just kind of learning how it's supposed to sound. I've been running the PWK for nearly 2 seasons now and it runs great. Usually starts on 2nd or 3rd kick when cold, idles well and transitions well from 1/4 to 1/2 to WFO. It's been running so well that I haven't even had to think about tinkering with the jetting.

Year & Bike Model = 2009 WR300
Carb = Keihin PWK 38
Gas/Mix = Chevron Premium/Klotz R50 @ 40:1
Pipe & Silencer = 'New' Pro Circuit Platinum 2/Type 296 silencer
Temperature range (deg F) = 50-55f
Elevation (feet) = 1500-200'
Main jet = 175
Pilot jet = 45
Needle = N3EJ
Clip position = #2
Air screw setting = 1.5 - 2
Slide = 7
Conclusions/Results = BINGO! That leaner needle and the smaller main jet were spot on for my local ride spot. Pilot felt a little fat, but could probably have been tuned out with the air screw. I was having too much fun to worry about it though

Year & Bike Model = 1999 WR360
Carb = Keihin PWK 38 AirStriker
Pipe & Silencer = FMF Fatty pipe / standard eu model
Other engine mods = "the airboot intake mod"
Premix ratio & fuel type = 1:50 (2%) currently MAXIMA Castor 927 (otherwise Castrol Power1 TTS Fully synthetic). 98 octane
Temperature range (deg F) = 10C (50F)
Elevation (feet) = Sea level
Main jet =172
Pilot jet =42
Needle = n/a
Clip position = 2nd
Air screw setting = 1 3/4
Slide = n/a
Conclusions/Results = Switched to PWK from TM38 today. Amazing results. I really couldn't get the Mikuni to run perfectly. The new carb fired up on the first kick. After adjusting the throttle height and air mixture/speed the PWK idled perfectly steady. Respons was also good, felt almost like a smaller cc bike The best of it all was that it ran clean all the way to the top revs, even if I'd been on low revs for a while. The main 172 and pilot 42 was just a lucky shot. I googled some threads about jetting the pwk on the 360 and figured it should be something like this. PWK FTW


Edit: added fuel type.
Also, changing carbs was a job that didn't take long at all. Some people say you need to release and lift up the alu sub frame but that is not necessary (as long as your airbox rubber connection still is soft). The PWK body is a bit "longer" compared to the TM but still fully possible without causing any damage.

Year & Bike Model = 2008 WR250
Carb = Keihin PWK 36mm Quad Vent (yes I said 36mm)
Pipe & Silencer = Stock pipe with FMF turbine core 2 spark arrestor
Other Engine Mods = None
Premix & Fuel = 50:1 Amsoil Interceptor w/ 91 or 93 octane.

Temperature range (deg F) = 85-95 degF
Elevation (feet) = ~1000 feet
Main jet = 175
Pilot jet = 48
Needle = DDK
Clip position = #3
Air screw setting = 1.75 turns out
Slide = 6.0

Hi the Sweden man !
For me, this little piece of metal is a joy !
I have ordered it directly from Scaryfast and have receive it in 3 business days.

My current jetting on my WR300 2010 is:
Keihin PWK 38mm AS
Main Jet : 178
Pilot Jet : 42
Needle : CEL, 2nd clip from the top
Slide : #7
Air screw: 1 1/2
Fuel/oil mix : 40/1 with Mothul 800

Yesturday i have ride 3-4 hours and the jetting is really spot on. No miss, no ping, very responsive down low and so strong from middle to top. This motor is now more user frendly since the bottom end is more strong (that reduce the big hit when it goes on the pipe).
This week i will put 1 or 2 more teeth on the front sprocket... im sure the motor will take it no trouble now.

Year & Bike Model = WR360 2000
Carb = PWK 38mm
Pipe & Silencer = Stock
Other engine mods = Auto-decompression Head
Premix ratio & fuel type = 40:1, Motul 800. Premium unleaded (93 Octane, I think)
Temperature range (deg F) = 28c (~81f)
Elevation (feet) = Sea level for testing, but I normally ride between 1000 - 4000feet.
Main jet = 170
Pilot jet = 40
Needle = R1369LS (Somewhere around a CEK needle, I think)
Clip position = 2nd
Air screw setting = 1.5 turns
Slide = 6.0
Conclusions/Results = Earlier today, I had the clip in the 3rd position and was running a 35 pilot jet. It idled, but it was still fluffy from 1/8 to 1/4 throttle. So I moved up to a 40 pilot (just because I figured a 35 is too lean) and the clip to the 2nd spot and it's run as clean as I've ever had it running.

I swapped to the PWK a couple of days ago, and this is the jetting I've settled on. I maybe running slightly too lean. I may have just got use to seeing my bike smoking a lot - now there is very minimal/if any smoke when the engine is warm.

Just went for a short ride on a new plug. It came out blackish - so still running rich, but nowhere like before. I'll ride it as is for a proper ride and see how it goes for a whole day.

JD Jet Kit Installed
Year & Bike Model =2007 WR250
Carb = Stock
Pipe & Silencer =FMF Gnarley/Turbine 2
Other engine mods = -
Premix ratio & fuel type = 50:1/92
Temperature range (deg F) = 0 to 30 c or 32 to 86
Elevation (feet) =0 to 5000ft
Main jet =390
Pilot jet =32.5
Needle = JD Blue
Needle jet = JD jet S4(?)
Clip position =middle pos.
Air screw setting =1 1/2 to 1 3/4
Slide =4.0
Conclusions/Results =Very good throttle response, very good low/mid/high end power and over rev

2009 wr 300

Here's my best settings

Temp 95 degrees
Humidity 80%
Altitude 950'

Fuel VP 110 50:1 Motul


Kehin 38mm PWK
165 MJ
CEL middle clip
35 PJ airscrew out around 1 1/2

It freakin rips with no bogging or flat spots. plug chop is light tan.

Will need to go to a 168 or 170 MJ when it cools off

Year & Bike Model = 2007 WR250
Carb = Stock
Pipe & Silencer =FMF Gnarly/ Turbine 2
Other engine mods =
Premix ratio & fuel type = 40:1
Temperature range (deg F) = 40-90, set at approx. 75 degrees
Elevation (feet) = 3200 is my elevation. But this jetting works everywhere for warmer days.
Main jet =400
Pilot jet =35/summer, 30/winter
Needle = stock
Clip position = 2nd from top
Air screw setting = 2 turn out
Slide = #3
Conclusions/Results = Good low end through mid and top. Seems weird at my elevation to need stock jetting on the pilot and main, but that's what it wants.
Note: Due to where I live, the dry climate is to blame. When it gets cold and wet, the 30 pilot is used. Otherwise it loads up and has a weak off idle rev.

Year & Bike Model = 2007 WR250
Carb = stock Mikuni
Pipe & Silencer = Stock silence & Gnarly Gold pipe
Other engine mods = nope
Premix ratio & fuel type = 40:1
Temperature range (deg F) = 10 - 30'C
Elevation (feet) = 0 - 500
Main jet = 380
Pilot jet = 28
Needle = stock
Clip position = 2nd ring from top
Air screw setting = 1.5
Slide = ?
Conclusions/Results = Good crisp bottom end revs - suits my slower (low rev) more technical trail riding. Tried the standard settings (400 main, 35 pilot, 3rd ring on needle) killed the spark plug every 2 hrs of riding.

I did some rejetting on my 300 today as it´s about 8-15 degrees Celsius here now at sealevel. I have Supermoto setting now with slicks, 15/38 gearing:

Keihin PWK 38 AS

Pilotjet 42, 2 turns out

JD Red needle in 2nd slot from top

180 mainjet

JD needle is smoother from the bottom than EEL, which is good on the streets when it´s cold and the slicks ain´t so sticky, otherwise EEL in 2nd slot from top is strong from the bottom for gnarly terrain.
Pulls good all the way and revs to the moon!

Johnny:sweden:

Year & Bike Model = 1996 WR360
Carb = KEIHIN PWK 38MM AS
Pipe & Silencer = FMF Gnarly and FMF Powercore
Other engine mods = N/A
Premix ratio & fuel type = 40:1 sometime 33:1
Temperature range (deg C) = 15 to 25C up to 36C
Elevation (metres) = 0-800m
Main jet =170 to 175 (summer)
Pilot jet =38 to 40 (summer and higher elevation)
Needle = JD Blue
Clip position = 2nd
Air screw setting = 2
Slide = #7
Conclusions/Results =
After much fooling around and my style of riding that the 0-1/2, the combination of a 38 Pilot, 2 turns out and 2nd Clip and Slide 7 is about spot on for my base line setting. I have to be careful with the Clip and 170 main if l'm riding wide open trails or summer
Most of the fouling issues now are due to poor warming technique (in winter).

Hi, All
I will give the spec's my bike runs in Sydney Australia

Year & Bike Model = 2008 WR 250
Carb = TMX38
Pipe & Silencer = DEP PIPE & FMF TURBINE CORE 2
Other engine mods = 0
Premix ratio & fuel type = 98OCT 50:1 MOTUL 800
Temperature range (deg C) = 18-20
Elevation (meters) = 250
Main jet = JD 390
Pilot jet = JD 30
Needle = JD RED
Clip position = 3RD
Air screw setting = 2 1/4
Slide = 3
Air filter: Twin Air

Conclusions/Results = my bike was real bad to ride. The float level was 2mm too high. This was a constant cause of fouling plugs. I would foul 2-3 plugs every ride, this would happen riding in the lower rev range on tight tracks. On down hill descent, I would get to the bottom twisting the throttle only to foul another plug. The high float level was the cause of flooding, burning off the fuel, but not all the oil. I also had the same problems riding on flat ground in the lower rev range. Heavy braking would also fuel the engine up and foul another plug. On cold start up my bike would moan and cough. I was at the point of no return, this constant headache had to go.

The above specs are a recipe that has now produced a nice clean crisp bike. On cold start up, I do not require the choke. The engine spins up very quick with no moan, and no longer fouls plugs. The bike now rides like a dream, pulls hard off the bottom right through to the top end

With that jetting and pipe combo, my bike produced on the dyno
42rwhp, 26ft/lb torque @ 8500rpm.

A big thank you to Steve Cutting
@ Motorcycle Weaponry 7/8 Wilmette Pl
Mona Vale
NSW
Australia
Ph: 029979 4744
Fax: 029979 4745
Motorcycle Weaponry is also on the Net[/U][/U]

Hi Johnny,

Yes I did try the 35 & 32.5 pilot, 380, 390 & 400 main
35 & 32.5 pilots were too rich off the bottom
380 main was a fraction too lean on WOT
400 main was a fraction too rich on WOT

The 08 WR250 Carb is a slightly different set up to to 09-10 although they do look the same
I have a number 3 slide making the settings rich enough for the 390 main

The higher the number on the slide eg: 4.0, 4.5, 5.0 you will find they take a
higher number on the main jet eg: 400, 410, 420, 430, 440

The factory float level settings were my biggest problem

I was seeking a reliable bike that I can ride without any problems,
I did not anticipate that it would become a two wheel weapon

Regards Col

Hey guys,
Put a PWK on my 09 300. It currently has the red JD needle on the middle clip, 170 main, 45 pilot and the air screw at 1 1/2 turns. Bike runs great down low and thru the mid. Up top it goes flat and runs poorly. Should I go to a 168 main or? Bike has a Gnarly pipe and Turbine muffler. I will be riding around the 5000' to 6000' this winter.
Thanks

verify your main jet as per:

http://www.cafehusky.com/forums/showthread.php?t=14651

lemme know if you still have issues.