STIC Carb Metering insert for Keihin PWK38, PWK36 and PWK28, fits both screw top and electronic Powerjet types
This STIC metering block for keihin carbs is a shocker in both our dyno and field testing. Great gains in power, throttle response, acceleration, and overall performance.
Please allow 5-10 business days for product shipment. We build our blocks to order and undergo a QC process on each one to ensure your product is how it should be!
Email email@example.com for any additional info or fitment questions.
Carb Machining Stage 2 Modifications
We also have stage 2 modification for the Keihin carb, which includes extensively developed bore work, shaping, and jetting set to be used in conjunction with the STIC insert. This modification is worth around 1hp.. We modify the electronic power-jet circuit as well. It's a perfect mate for the STIC system - making use of the superior fuel atomization and coupling it with drastically improved flow and signal, while allowing additional volume for space taken up by fuel converted to vapor. It's an incredible value for the power.
Powerjet Type - $200 USD
Non Powerjet Type - $125 USD
85CC and Supermini Carb Bore/HP mod- $125 USD
Our Independent Dyno Testing Results
How To: Video instructables on Installation and Needle Jet
STIC DVI Keihin Metering Block 38PWK 36PWK "E" Type
Fits NON screw top PWK38mm - Common to KX250, RM250, YZ250, KTM 125, KTM150, KTM250, KTM300, and PWK called "short body"
Great Dyno proven gains, incredible throttle response, improved performance in all conditions.
,114 needle jet, if you want a .115 or .116 please add those versions to cart!
Limited Time: FREE U.S. shipping!
STIC DVI Keihin Metering Block For 38PWK and 36PWK "M" Type
For screw on top Keihin PWK carbs. Great gains in power, acceleration, throttle response, and performance. Unlock the hidden potential!
This carb is a "long body" common to a 2000 cr250, or older generation 125's and 250's.
.114 needle jet - if you want a .115 or .116 please add those versions to cart!
Limited time: FREE U.S. Shipping!
Frequently asked Questions:
What fuel do I need?
We recommend a minimum of 98 octane combined rating ((RON)+(MON))/2, one fuel that meets this requirement is VP MS98, or a 50% percent blend of VP C12 and 91 Pump gas. The consistency of pure race fuels is also very good compared to pump gas as an added tuning benefit. Another option we highly suggest is Avgas 100LL mixed 4.5 gallons to .5 gallons of pump gas for those on a tighter budget. We have found on the KTM models, pump gas is sufficient as well as the stock honda models, beta, gas gas, and sherco.
Why do I need higher octane rating?
Most production motorcycles are highly developed from the manufacturer to run right up to the limit if 89-91 pump gas as long as they are jetted a little too rich for max performance. Sadly most OEM development was done on two strokes before pump gas changed formulation to the ethanol/oxygenated blend we have now making many two strokes incapable of running pump gas stock unless grossly rich. The compression ratio selected by the OEM is right up the limit before detonation. When increasing power, the dynamic compression ratio increases, and total heat production increases (piston engines are heat pumps - converting heat into power). Due to this - a higher grade fuel is necessary - or a reduction in compression ratio.
Will my engine life be affected?
The engine must be in good mechanical order prior to any increase in power, from any modification. Outside of this, no. The engine life will be the same as it was before as long tuning is correct.
What jetting is suggested?
Most bikes requires a main jet that is +4-5 sizes from before, and a pilot jet +1-2 sizes. We personally highly suggest that bikes using an electronic powerjet KEEP using it.
These are some rough guidelines for users around 1000 feet and 60ish degrees. For higher altitudes start here and use the air screw to determine if any changs are needed. The KTM's have been pump gas freindly.
For CR 250 - 188-190 main 48 pilot
RM 250 - 188-190 main 48 pilot
KX 250 - 168-172 main 48 pilot .114 needle jet tube
YZ250 195main 55 pilot .114 needle jet tube
KTM/Husly 150 and 125 - 50-55 pilot, 192-195 main OEM needle, OEM clip .114needle jet tube
KTM/HUsky 250SX (36mm) 42 pilot, 170-172 main OEM needle 1 clip leaner than stock Air screw 1.5-2 .114 needle jet tube
KTM/Husky 300 XC/XCW/SX (36mm) 42-45 pilot 175-78 main OEM needle 1 clip leaner than stock Air screw 1.5-2 .114 needle jet tube
KTM/Husky 250 (38mm) 50-55 pilot, 190-195 main OEM needle OEM position .114 needle jet tube
KTM/Husky 300 (38mm) 50-55 pilot 190-195 main OEM needle OEM position .114 needle jet tube
Best universal Needle: N3EW or NCEW - works on almost all models extremely well but is too lean for sea level and low humidity for KTMs on 38mm
How does the STIC work?
The STIC utilizes some patent pending technology never prior seen in carburation. The most simple explanation is the STIC both vaporizes the fuel more thoroughly at all throttle openings as well as provides a self escalating fuel curve that is capable of supplying enough fuel at part throttle openings to support more HP than prior systems. The result is a bike that is more responsive in transition, more powerful at low throttle openings (and WOT), and more linear in feel. Most 2 stroke owners complain on all 2 strokes they wish they had more "low end" or "bottom end". While this isn't entirely accurate - what they really want is more power at lower throttle openings.