Carburetor Kit - CRF150F - 2006-2011 - Repair and Tuning

The Keyster FH-8070N Carburetor Repair and Tuning Kit is designed for the Keihin PDD-series piston-valve carburetors used on 2006-2009 Honda CRF150F motorcycles. It combines the primary sealing, fuel-control and adjustment components needed for a thorough carburetor rebuild with a selection of main jets, slow jets and D704-series jet needles for tuning the motorcycle after the carburetor has been returned to proper mechanical condition.

The Honda CRF150F uses a single carburetor, so Qty 1 FH-8070N kit services the complete original carburetor assembly.

Honda CRF150F Fitment

• 2006 Honda CRF150F
• 2007 Honda CRF150F
• 2008 Honda CRF150F
• 2009 Honda CRF150F

The existing product title references 2006-2011, but the detailed application data lists only 2006-2009 CRF150F models. For accurate catalog fitment, this kit should therefore be presented as a 2006-2009 application unless additional model-specific information confirms otherwise.

Keihin PDD6D / PDD6F Carburetors

Honda revised the CRF150F significantly for 2006, including the carburetor specification. U.S.-market 2006-2007 motorcycles use the Keihin PDD6D carburetor, while 2008-2009 models use the later PDD6F version.

Both are mechanically operated piston-valve carburetors. Throttle movement directly raises and lowers the slide while the slow circuit, jet needle, needle jet and main jet progressively control fuel delivery as throttle opening increases.

Keyster FH-8070N Kit Contents

• Float Chamber Gasket
• Spring Seat
• #39 Pilot / Slow Jet
• #40 Pilot / Slow Jet
• #42 Pilot / Slow Jet
• #90 Main Jet
• #92 Main Jet
• #95 Main Jet
• #98 Main Jet
• #102 Main Jet
• #107 Main Jet
• D704-L Jet Needle
• D704-S Jet Needle
• D704-R Jet Needle
• D704-RR Jet Needle
• Needle Jet
• Float Needle Valve
• Pilot Screw
• Pilot Screw Spring
• Pilot Screw Washer
• Pilot Screw O-Ring
• Throttle Screw
• Throttle Screw O-Ring
• Throttle Screw Spring
• Drain Screw
• Drain Screw O-Ring
• 2 Additional O-Rings
• 4 E-Clips

Repair and Tuning Jet Selection

FH-8070N is a repair-and-tuning kit rather than a fixed-jet carburetor rebuild kit. It provides several fuel-metering options around the original CRF150F calibration so the carburetor can be repaired and then adjusted for changes in intake, exhaust, elevation and operating conditions.

• Main Jets: #90, #92, #95, #98, #102 and #107
• Pilot / Slow Jets: #39, #40 and #42
• Jet Needles: D704-L, D704-S, D704-R and D704-RR

The included sizes are tuning options rather than a recommendation to install the largest available jets. Carburetor tuning should begin from a known baseline and changes should be made methodically.

Stock CRF150F Jetting Baseline

Honda service information for the post-2005 CRF150F specifies a #95 main jet and #40 slow jet for the original PDD-series carburetor.

• Standard Main Jet: #95
• Alternate Main Jet: #90
• Slow Jet: #40

The Keyster FH-8070N kit includes all three of these Honda reference sizes within its broader tuning selection. For an otherwise stock motorcycle that ran correctly before carburetor wear or contamination occurred, the #95 main and #40 slow combination provides the appropriate starting reference.

Before removing the original components, record the installed main jet, slow jet, needle identification and clip position. Previous owners may already have changed the carburetor calibration for elevation, intake or exhaust modifications.

Main Jet Tuning

The main jet has its greatest influence at larger throttle openings and higher engine loads. FH-8070N includes six main jets ranging from #90 through #107, providing both leaner and richer alternatives around the standard #95 configuration.

A larger-numbered main jet generally allows greater fuel flow through the main circuit, while a smaller jet reduces fuel flow. Select jetting according to the motorcycle's actual configuration and engine response rather than automatically installing a richer jet whenever an aftermarket component has been added.

Pilot / Slow Jet Tuning

The slow jet controls a major portion of fuel delivery during starting, idle and small throttle openings. FH-8070N includes #39, #40 and #42 slow jets, with the original #40 specification positioned in the middle of the supplied range.

Before changing slow-jet size, thoroughly clean the pilot circuit and inspect the intake system for leaks. A blocked pilot passage or leaking intake boot can produce lean-running symptoms that should not be corrected simply by installing a larger slow jet.

D704 Jet Needle Selection

The kit includes four D704-series jet needle calibrations: D704-L, D704-S, D704-R and D704-RR. These needles provide alternate fuel-metering profiles through the part-throttle operating range.

The jet needle works together with the needle jet as the throttle slide rises. Needle profile and clip position can both affect mixture, so record both the installed needle and E-clip position whenever tuning changes are made.

Change one tuning variable at a time whenever practical. Changing the main jet, slow jet and needle simultaneously can make it difficult to determine which adjustment caused a particular change in engine behavior.

Float Needle Valve

The included float needle valve controls gasoline entering the float chamber. As the fuel level rises, the float pushes the valve closed. As the engine consumes fuel, the float drops and allows the chamber to refill.

A worn, contaminated or sticking float valve can contribute to fuel leakage, carburetor flooding, rich operation or inconsistent fuel level. Honda used different float-valve service references during this production period, including 16011-KCK-910 on earlier PDD6D applications and 16011-KPS-921 on later PDD6F applications.

Inspect the float for damage and free movement during service and verify the correct float level after installing the replacement valve.

Honda OEM Cross-References

Several components serviced by Keyster FH-8070N correspond with original Honda parts used in the 2006-2009 CRF150F PDD-series carburetors:

• 16010-KCN-751: Carburetor Gasket Set
• 16011-KCK-910: Earlier Float Valve Set
• 16011-KPS-921: Later Float Valve Set
• 16012-KPT-A01: Jet Needle Set
• 16016-KSJ-A01: Screw Set A
• 16028-KEH-900 / 16028-KEB-G01: Screw Set B references
• 16075-GHB-B70: O-Ring, 2.4 x 29mm
• 16075-GHB-640: O-Ring, 1.3 x 4.3mm
• 16163-KCS-920: Float Chamber Gasket
• 99113-GHB-0950: #95 Main Jet
• 99113-GHB-0900: #90 Main Jet
• 99103-KPT-0400: #40 Slow Jet

For carburetor identification, the 2006 CRF150F uses Honda carburetor assembly reference 16100-KPT-A02 for the PDD6D assembly, while later 2008-2009 applications use 16100-KPT-A22 for the PDD6F assembly.

These Honda numbers are provided for identification and component cross-reference purposes. FH-8070N contains Keyster replacement and tuning parts rather than Honda-branded OEM components, and the alternate tuning sizes supplied in the kit are not all original Honda specifications.

Float Chamber Gasket and O-Rings

The float chamber gasket and O-rings seal areas continuously exposed to gasoline and fuel vapor. Age, heat and repeated carburetor service can cause the original seals to harden, flatten, shrink or tear.

Remove old gasket material carefully and clean all sealing grooves and mating surfaces before installing the replacement components. Avoid aggressive scraping tools that can damage the aluminum carburetor body.

Pilot, Throttle and Drain Screw Components

FH-8070N includes replacement pilot, throttle and drain screw components along with their associated springs, washers and O-rings. These small components can become damaged, corroded or lost during previous carburetor service.

Never force the pilot screw tightly against its seat. Turn it inward only until lightly seated when establishing a baseline adjustment, then follow the appropriate Honda service procedure for final setup.

Clean Before Tuning

Carburetor tuning should begin only after the carburetor is mechanically sound and thoroughly clean. Larger jets cannot correctly compensate for blocked internal passages, incorrect float level, intake leaks or contaminated gasoline.

Thoroughly clean the slow circuit, main circuit, needle-jet passage and float-valve passage before installing the replacement components.

If rust, sediment or degraded fuel is found in the carburetor, inspect the fuel tank, petcock and fuel line before returning the motorcycle to service. Contamination remaining upstream can quickly reach the new float valve and jets.

One Kit Services the Complete CRF150F Carburetor

Keyster FH-8070N services one carburetor. Because the Honda CRF150F uses a single Keihin carburetor, Qty 1 kit is required for a complete carburetor rebuild and tuning setup.

Important Installation and Tuning Notes

• One kit services one carburetor; Qty 1 services the complete original CRF150F carburetor.
• Keyster reference FH-8070N.
• Catalog fitment supported by the detailed application data is 2006-2009 Honda CRF150F.
• 2006-2007 U.S. applications use the Keihin PDD6D carburetor.
• 2008-2009 applications use the Keihin PDD6F carburetor.
• Stock Honda jetting is #95 main and #40 slow.
• Honda also lists a #90 alternate main jet.
• Includes six main jets: #90, #92, #95, #98, #102 and #107.
• Includes three slow jets: #39, #40 and #42.
• Includes four D704-series tuning needles: D704-L, D704-S, D704-R and D704-RR.
• Record the existing jetting, needle and clip position before making changes.
• Change one tuning variable at a time whenever practical.
• Inspect and clean all internal fuel and air passages before tuning.
• Check float operation and fuel level after replacing the needle valve.