Sirris F43 Trail Tune Ultra Bee Fork

Take your Ultra Bee to the next level with the Sirris F43 Trail Tune Fork, engineered for riders who want performance, precision, and confidence across every trail. The Trail Tune delivers a perfect mix of sportiness and comfort — designed to go fast, handle aggressively, and stay stable over all types of terrain.

Whether you’re carving through corners, flying over jumps, or cruising rugged tracks, this fork gives you unmatched control and support. Every movement feels precise, every landing smoother, and every ride more powerful.

With the Sirris F43 Trail Tune, you’ll transform your Ultra Bee into a trail-dominating machine — ready for anything the ride throws at you.

Rider Weight Specs

Sirris offers six weight-specific setups to give every rider the perfect suspension balance.
(Listed weights exclude gear; 15 lbs of riding gear is already factored in.)

• LIGHT: 59–72 kg / 130–160 lbs → (4.0 / 4.0 springs)

• MEDIUM: 72–95 kg / 160–210 lbs → (4.8 / 4.4 springs)

• HEAVY: 95–105 kg / 210–230 lbs → (5.0 / 4.8 springs)

• X HEAVY: 105–114 kg / 230–250 lbs → (5.0 / 5.0 springs)

• XX HEAVY: 114–127 kg / 250–280 lbs → (5.4 / 5.0 springs)

• XXX HEAVY: 127–158 kg / 280–350 lbs → (5.8 / 5.4 springs)

(Fork spring rates are shown as left side / right side.)

Every fork is precision-tuned to deliver the ideal damping, rebound, and stiffness for your specific weight and riding style.

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 Trail Tune Fork from eBikePartsNZ?

At eBikePartsNZ, we don’t just sell suspension — we deliver race-proven performance and expert tuning for real riders.

✅ 100% genuine Sirris products
✅ Professionally tuned for trail versatility
✅ Perfect match for Surron Ultra Bee
✅ Fast, secure shipping within New Zealand
✅ Local experts ready to assist with setup & tuning