OTK Genuine 50mm Rear Axle

The OTK Genuine 50mm rear axle is a replacement and setup axle for compatible OTK-based kart chassis. Available in different lengths and hardness options, it is ideal for kart setup, race preparation and replacing worn or damaged axles.

Sourced directly from OTK, this is a genuine manufacturer component designed to fit OTK-based chassis to the correct specification. Whether you are replacing a worn or damaged axle, preparing for a race weekend or fine-tuning your kart's handling balance, this axle is a reliable, competition-ready choice for racers, mechanics and teams running compatible OTK-based machinery.

Rear axle selection is one of the most influential chassis setup decisions in karting. The stiffness of the axle directly affects how the rear of the kart behaves through corners, under braking and on corner exit. A harder axle tends to reduce rear flex, which can improve stability and suit higher-grip circuits, heavier drivers or conditions where the kart is already generating strong rear traction. Softer options allow more chassis movement, which can help the kart work in lower-grip conditions or on circuits where rear-end rotation is needed. Choosing the correct axle hardness for your conditions, class and driving style is an important part of competitive kart setup.

Key features:

• Genuine OTK rear axle — not an aftermarket or pattern part
• 50mm diameter, compatible with OTK-based chassis using a 50mm rear axle specification
• Available in 1000mm and 1030mm lengths depending on variant
• Available in multiple hardness options depending on variant
• Suitable for Tony Kart, Kosmic, Exprit, LN Kart, EOS, Red Speed, Carlos Sainz 55 and Gillard chassis
• Sold individually

Variant guide:

• Length: Available in 1000mm or 1030mm — check your chassis specification before ordering
• Hardness: Options may include Medium, Hard, Extra Hard and Extra Extra Hard — availability depends on current stock
• Only variants shown as available in the product listing are currently in stock

Setup note:

Axle hardness has a direct effect on kart handling. A harder axle generally reduces rear flex and suits high-grip conditions, heavier drivers or circuits where stability is the priority. A softer axle allows more chassis movement and can help the kart generate rear grip in lower-traction conditions. Always select your axle based on circuit conditions, class requirements, driver weight and setup advice from your team or mechanic.

Product details:

• Brand: OTK (genuine part)
• Diameter: 50mm
• Available lengths: 1000mm / 1030mm
• Hardness options: Medium / Hard / Extra Hard / Extra Extra Hard (subject to availability)
• Sold individually
• Axle keys, bearings, hubs and other fittings are not included

Compatibility note:

This axle is designed for OTK-based kart chassis using a 50mm rear axle. It is commonly used on the following chassis:

• Tony Kart
• Kosmic
• Exprit
• LN Kart
• EOS
• Red Speed
• Carlos Sainz 55
• Gillard

Before ordering, please confirm your chassis model, axle diameter, axle length, brake hub, sprocket carrier, wheel hub and bearing carrier compatibility. This axle is not a universal fit and is intended only for compatible OTK-based chassis using the 50mm rear axle specification.

Ideal for:

• Replacing a worn or damaged rear axle on an OTK-based chassis
• Kart chassis setup and rear-end grip adjustment
• Race preparation and testing
• Kart mechanics and race teams managing multiple chassis
• Owner-drivers maintaining or setting up their own kart
• Competitive karting across a range of classes and circuits

A genuine OTK component, built to the correct specification for competitive karting on compatible OTK-based chassis.