Carburetor Kit - CRF230F - 2007-2012 - Repair and Tuning

The Keyster FH-8075N Carburetor Repair and Tuning Kit is designed for the later Keihin PD-series piston-valve carburetors used on 2007-2009 and 2012 Honda CRF230F motorcycles. In addition to the sealing, fuel-control and adjustment components needed for a complete carburetor service, FH-8075N includes multiple main jets, slow jets and D703-series jet needles for tuning the motorcycle after the carburetor has been returned to proper mechanical condition.

The Honda CRF230F uses a single carburetor, so Qty 1 FH-8075N kit services the complete original carburetor assembly.

Honda CRF230F Fitment

• 2007 Honda CRF230F
• 2008 Honda CRF230F
• 2009 Honda CRF230F
• 2012 Honda CRF230F

The product title uses a 2007-2012 range, but the detailed application data specifically lists 2007, 2008, 2009 and 2012. For precise catalog fitment, those are the model years represented here.

Keihin PD9CD / PD9CF Carburetors

The 2007 CRF230F uses the Keihin PD9CD-series carburetor, while 2008-2009 and 2012 applications use the later PD9CF-series carburetor. Honda identifies the 2007 PD9CD B assembly as 16100-KPS-732 and the later PD9CF B assembly as 16100-KPS-A12.

These are mechanically operated piston-valve carburetors. Throttle movement directly controls the slide while the slow circuit, jet needle, needle jet and main jet progressively meter fuel as throttle opening increases.

Keyster FH-8075N Kit Contents

• Float Chamber Gasket
• Top Cover Gasket
• #41 Pilot / Slow Jet
• #42 Pilot / Slow Jet
• #45 Pilot / Slow Jet
• #96 Main Jet
• #98 Main Jet
• #102 Main Jet
• #106 Main Jet
• #110 Main Jet
• #115 Main Jet
• D703-L Jet Needle
• D703-S Jet Needle
• D703-R Jet Needle
• D703-RR Jet Needle
• Needle Jet
• Float Needle Valve
• Pilot Screw
• Pilot Screw Spring
• Pilot Screw Washer
• Pilot Screw O-Ring
• Throttle Screw
• Drain Screw
• Drain Screw O-Ring
• Additional O-Ring
• 4 E-Clips

Repair and Tuning Jet Selection

FH-8075N is a repair-and-tuning kit rather than a basic fixed-jet rebuild kit. It provides multiple fuel-metering options so the original carburetor can first be rebuilt and then adjusted for changes in intake, exhaust, elevation, temperature or other operating conditions.

• Main Jets: #96, #98, #102, #106, #110 and #115
• Pilot / Slow Jets: #41, #42 and #45
• Jet Needles: D703-L, D703-S, D703-R and D703-RR

The supplied sizes are tuning options and should not be interpreted as a recommendation to install the largest available jets. Start from a known baseline and make changes methodically.

CRF230F Reference Jetting

The fixed Keyster repair kit for this same CRF230F application is supplied with a #102 main jet and #42 slow jet, making those sizes a useful baseline when rebuilding an otherwise stock carburetor.

• Reference Main Jet: #102
• Reference Pilot / Slow Jet: #42

Honda OEM parts information also lists a #98 main jet for these carburetors. Because jetting can vary with market, operating conditions and previous modifications, record the components currently installed before making changes.

Main Jet Tuning

The main jet has its greatest influence at larger throttle openings and higher engine loads. FH-8075N supplies six main jets ranging from #96 through #115, with both #98 and #102 included in the selection.

Larger-numbered jets generally provide greater fuel-flow capacity through the main circuit, while smaller jets reduce fuel flow. Final selection should be based on the motorcycle's actual intake and exhaust configuration, altitude and engine response.

Pilot / Slow Jet Tuning

The slow jet controls a significant portion of fuel delivery during starting, idle and small throttle openings. FH-8075N includes #41, #42 and #45 slow jets, with the #42 reference size included in the middle of the supplied range.

Before changing slow-jet size, thoroughly clean the pilot circuit and inspect the intake system for air leaks. A restricted passage or intake leak can create lean symptoms that should not be corrected simply by installing a richer jet.

D703 Jet Needle Selection

FH-8075N includes four Keyster D703-series tuning needles: D703-L, D703-S, D703-R and D703-RR. These provide alternate fuel-metering profiles through the part-throttle operating range.

The original Honda jet needle assembly for these later CRF230F applications is cross-referenced by Honda OEM number 16012-KPS-731. The Keyster D703 needles are tuning alternatives and should not automatically be treated as four identical replacements for the original Honda needle calibration.

Needle profile and E-clip position can both affect part-throttle mixture. Record the installed needle and clip position before making changes so each adjustment can be evaluated or reversed.

Float Needle Valve

The included float needle valve controls gasoline entering the float chamber. As fuel level rises, the float closes the valve against its seat. As the engine consumes fuel, the float drops and allows the chamber to refill.

A worn, contaminated or sticking valve can contribute to carburetor flooding, fuel leakage, rich running or inconsistent fuel level. Later CRF230F parts data identifies Honda OEM 16011-KPS-921 as the float valve set.

Inspect the float for damage and free movement during carburetor service and verify the proper float level after installation.

Honda OEM Cross-References

Several components serviced by Keyster FH-8075N correspond with original Honda parts used in the 2007-2009 and 2012 CRF230F carburetors:

• 16100-KPS-732: PD9CD B Carburetor Assembly - 2007
• 16100-KPS-A12: PD9CF B Carburetor Assembly - later applications
• 16010-KCE-670: Carburetor Gasket Set
• 16011-KPS-921: Float Valve Set
• 16012-KPS-731: Jet Needle Set
• 16014-KPS-851: Carburetor Top Set
• 16016-KC2-764: Screw Set A - earlier application
• 16016-KPS-A11: Screw Set A - later application
• 16075-GHB-640: O-Ring, 1.3 x 4.3mm
• 16163-KCS-920: Float Chamber Gasket
• 99113-GHB-1020: #102 Main Jet
• 99113-GHB-0980: #98 Main Jet
• 99103-MV9-0420: #42 Slow Jet

These Honda OEM numbers are provided for component identification and cross-reference purposes. FH-8075N contains Keyster replacement and tuning components rather than Honda-branded OEM parts, and the additional tuning sizes included in the kit do not all correspond to the original factory calibration.

Float Chamber and Top Cover Gaskets

The float chamber and carburetor top are opened during major service, and their original sealing components can harden, shrink, tear or remain permanently compressed after years of fuel exposure and heat.

Clean the gasket grooves and mating surfaces carefully before installing the replacement components. Avoid aggressive scraping tools that can damage the aluminum carburetor body.

Pilot, Throttle and Drain Screw Components

FH-8075N includes replacement pilot, throttle and drain screw components along with the associated spring, washer 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 procedure for final tuning.

Clean Before Tuning

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

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

If rust, sediment or degraded fuel is found inside the carburetor, inspect the fuel tank, petcock and fuel line before returning the motorcycle to service.

One Kit Services the Complete CRF230F Carburetor

Keyster FH-8075N services one carburetor. Because the Honda CRF230F 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 CRF230F carburetor.
• Keyster reference FH-8075N.
• Detailed catalog fitment is 2007-2009 and 2012 Honda CRF230F.
• 2007 applications use the Keihin PD9CD-series carburetor.
• Later applications use the Keihin PD9CF-series carburetor.
• Reference jetting is #102 main and #42 slow.
• Includes six main jets: #96, #98, #102, #106, #110 and #115.
• Includes three slow jets: #41, #42 and #45.
• Includes four D703-series tuning needles: D703-L, D703-S, D703-R and D703-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.