Sirris F43 MX Tune Ultra Bee Fork – Built for Maximum Control & MX Power

Experience the next level of motocross performance with the Sirris F43 MX Tune Fork, purpose-built for the Surron Ultra Bee. Designed for balance, precision, and unbeatable bottoming resistance, this fork gives riders firm suspension for extreme control and support—perfect for high-speed jumps, whoops, and aggressive cornering.

With the MX or EBMX spec, you’ll gain a stiffer, more responsive setup, trading a bit of trail softness for superior bottoming resistance and stability on rough terrain. Whether you’re a competitive racer or an off-road enthusiast, the Sirris F43 MX Tune Fork ensures smoother handling, better feedback, and total riding confidence.

Rider Weight Specs

Sirris offers five weight-specific setups to match your riding style and performance needs.
(Weight ranges are based on rider weight without gear. 15 lbs of riding gear is already included in calculations.)

• LIGHT: 54 – 73 kg / 120 – 160 lbs → (4.4 / 4.4 springs)

• MEDIUM: 73 – 91 kg / 160 – 200 lbs → (5.0 / 4.8 springs)

• HEAVY: 91 – 109 kg / 200 – 240 lbs → (5.4 / 5.0 springs)

• X HEAVY: 109 – 127 kg / 240 – 280 lbs → (5.4 / 5.4 springs)

• XX HEAVY: 127 – 145 kg / 280 – 320 lbs → (5.4 / 5.4 springs)

(Fork spring rates listed as left side / right side.)

Fork Specifications

• Architecture: Upside-down fork

• Travel: 246 mm

• Free Length: 856 mm

• Weight (with clamps & steerer): 22 lbs / 10 kg

• Stanchions: Ø43 mm high tensile steel, hard chrome coated

• Outer Tubes: Seamless 7050 aluminum, Type 3 hard anodized coating

• Drop Outs: Forged 6061 aluminum, Type 3 hard anodized coating

• Triple Clamps: Forged 6061 aluminum, Type 3 hard anodized coating

• Steer Tube: Seamless 7050 aluminum, Type 2 anodized coating

• Damping: Symmetrical, adjustable closed cartridge with spring-backed IFP

• Damper Bodies: Seamless 7050 aluminum, Type 3 hard anodized coating

• Rebound: Dual side high tensile steel spring, adjustable

• Adjusters: External compression and rebound adjustment

• Seals: NBR

• Guards: High-impact PP, 210° wraparound

Why Buy the Sirris F43 MX Tune Fork from eBikePartsNZ?

When you order from eBikePartsNZ, you’re not just buying a fork — you’re investing in race-proven quality, precision tuning, and trusted local expertise.

• 100% genuine Sirris components
• Optimized for Ultra Bee and NZ terrain
• Fast, secure shipping
• Expert local support & service
• Trusted by professional e-MX riders