OTK Genuine 50mm Rear Axle

Axle selection is one of the most consequential setup decisions in karting. The stiffness of the rear axle directly influences how the chassis transfers load through corners — a stiffer axle reduces rear flex and can help the kart maintain stability in high-grip conditions, while a softer axle allows more chassis movement and can assist rear-end rotation in lower-traction situations. The 0054G0 is the genuine OTK 50mm rear axle for OK, OKJ, and single-speed class chassis, available in two lengths and a full range of hardness grades to cover a wide variety of circuits and conditions.

Key Specifications

• Part Number: 0054G0
• Diameter: 50mm
• Available Lengths: 1000mm / 1030mm
• Class: OK / OKJ / Rotax / IAME X30 and other single-speed classes
• Sold individually — keys, bearings, and hubs not included

Hardness Grades

Grades run from softest to hardest. Availability varies by length.

• U — Super Soft
• Q — Soft
• N — Medium
• A — Medium Hard
• H — Hard
• HH — Extra Hard
• HD — Extra Extra Hard

Compatibility

Tony Kart

• Racer 401 RR
• Racer 401R
• Racer 401S
• Racer 401 T
• Racer 401 TDX

Kosmic

• Mercury RR
• Mercury R
• Mercury T
• Mercury TDX

Exprit

• Noesis RR
• Noesis T
• Noesis TDX

LN Kart

• LN Four
• LN Four T
• LN Four TDX

Redspeed

• RX RR
• RX T
• RX TDX

Other OTK Group

• CS55 MY2025
• EOS
• Gillard TG17

When replacing an axle, also check the axle bearings and bearing carriers for wear, and inspect the brake disc carrier and sprocket hub for correct seating on the new axle. The 1030mm length is the standard fitment on the majority of current OTK Group chassis — confirm your chassis specification before ordering if you are unsure whether 1000mm or 1030mm is correct.

Workshop Tip: Check axle straightness before fitting by rolling it on a flat surface or supporting it between centres. Even minor bends from an impact will cause vibration through the chassis and can accelerate bearing wear. An axle with visible deflection should be replaced rather than straightened.