SUPRAX Gearbox Main Counter Shaft + Shift Fork Set Heavy Duty Transmission Replacement Parts

• High-Strength Alloy Steel Construction: Adopts premium alloy steel with integral forging and heat treatment process, effectively improves overall hardness and torsion resistance, avoids shaft bending, fracture and tooth surface wear caused by long-term high-load operation.
• Precision CNC Machining: Strict micron-level tolerance control for shaft diameter, gear tooth pitch and shift fork size. High coaxiality ensures smooth rotation of the transmission shaft without jitter, greatly improving gear meshing accuracy.
• Stable & Smooth Gear Shifting: The matched shift fork precisely pushes the sliding gear to engage and disengage, solves common problems such as difficult gear shifting, gear jumping, gear slipping and shifting jamming, makes gear operation crisp and smooth.
• Excellent Wear & Corrosion Resistance: Fine surface grinding and anti-oxidation coating reduce internal friction of the gearbox, prevent metal oxidation and oil corrosion, adapt to long-term high-speed riding and complex road conditions.
• 100% OEM Perfect Fit: Completely consistent with the original SUPRAX transmission assembly parameters, no secondary modification needed during installation, effectively saves maintenance time and labor cost.
• Complete Gearbox Repair Kit: Integrates main shaft, counter shaft and shift fork core parts, one-stop solution for SUPRAX gearbox aging and failure, ideal for personal maintenance and repair shop batch replacement.

This complete SUPRAX transmission kit including main shaft, counter shaft and shift fork is the core assembly of the motorcycle gearbox power transmission system. The main shaft and counter shaft undertake the key task of engine power output and gear torque conversion, while the shift fork controls the accurate engagement and separation of each gear, which determines the smoothness, stability and safety of the whole vehicle’s shifting and driving performance. After long-term use, the original factory shafts are prone to tooth surface wear, shaft body deformation, coaxial deviation, and the shift fork is easy to wear and deform, resulting in typical faults such as difficult gear shifting, automatic gear jumping, gear slipping during acceleration, abnormal gearbox noise, and even power interruption, seriously affecting riding experience and driving safety.

Our SUPRAX main and counter shafts are made of high-quality industrial-grade alloy steel, processed through integral forging, high-temperature quenching and tempering heat treatment technology. Compared with ordinary carbon steel accessories, this product has stronger torsion resistance, compression resistance and impact resistance, which can withstand high-frequency power impact and long-term high-load operation of the engine, effectively preventing shaft bending, tooth breakage and fatigue deformation. The surface adopts precision grinding and anti-rust and anti-oxidation treatment, which reduces the friction coefficient between gears and shafts, lowers gearbox operating noise, and avoids part oxidation and wear caused by long-term immersion in engine oil.

Supporting matched shift fork set is manufactured according to original OEM standard data. The fork head curvature, spacing and thickness are precisely calibrated to ensure accurate clamping and pushing of the sliding gear. It can effectively eliminate the jamming and lagging of inferior shift forks during gear shifting, realize quick and accurate gear engagement, and thoroughly solve the problems of loose gear and unstable power output of old and worn gearbox parts. All key dimensions are strictly in line with the original car assembly standards, with high matching degree and good interchangeability.

No extra cutting, drilling or modification is required during the entire installation process. It can directly replace the original worn, damaged and failed main shaft, counter shaft and shift fork assembly. It perfectly repairs various gearbox failure problems, restores the original smooth shifting feeling and stable power transmission performance of the motorcycle, and prolongs the overall service life of the SUPRAX gearbox. This all-in-one transmission repair kit is suitable for daily maintenance, fault overhaul and old vehicle parts replacement of SUPRAX motorcycles, and is also a high-quality bulk supply accessory for motorcycle repair shops and parts wholesalers.

We provide stable inventory and flexible wholesale prices. All products undergo strict dimensional inspection and performance testing before delivery to ensure stable quality and reliable use. If you need bulk customization or batch orders, please contact us for exclusive preferential policies.