K-Tech RAZOR-R Shock Absorber Kawasaki Ninja 400 (2018-2023) 279S-018-150-005

The K-Tech RAZOR-R shock absorber sets a new standard in rear suspension for the Kawasaki Ninja 400, engineered from the ground up with premium materials and a fully adjustable damping architecture that leaves the factory unit far behind. From its precision-machined 35 mm body to its hardened 14 mm piston rod, every component reflects the exacting tolerances K-Tech is known for across British Superbike and World Supersport paddocks.

Key Features

• 14-click compression damping adjustment for fine-tuned response across road and track conditions
• 16-click rebound damping adjustment for precise control during rapid direction changes
• Adjustable spring preload accommodates a wide range of rider weights and load configurations
• Length adjustment (RCU travel 4.00 mm) allows ride height and handling balance to be dialled in
• Nitrogen (N2) charge at 10.00 bar eliminates aeration and maintains consistent damping under sustained hard use
• 46-150-140 spring included as standard; alternative spring rates available for individual rider requirements
• Direct OEM replacement fit — no modifications required for Ninja 400 (2018–2023)

Construction and Materials

The RAZOR-R is built around a 35.00 mm diameter aluminium body, hard-anodised for corrosion resistance and long service life. The 14.00 mm diameter piston rod is precision-ground and hard-chrome plated to resist wear and maintain seal integrity over tens of thousands of kilometres. Mounting eyes are machined to tight tolerances — the upper eye measures 30.00 mm wide with a 10.00 mm bolt diameter, and the lower eye 40.00 mm wide with a 10.00 mm bolt diameter — ensuring a solid, rattle-free installation with zero slop.

The nitrogen gas charge is sealed within a dedicated reservoir that keeps oil and gas separated, preventing foaming under the repeated compression cycles of spirited riding. The result is damping that remains linear and predictable whether you are commuting on a damp morning or chasing lap times at a track day.

On Road and On Track

Fitting the RAZOR-R transforms the Ninja 400 from a capable learner-sports machine into a chassis that responds precisely to rider input. The 65.00 mm stroke and 320.00 mm total length (with a tolerance of -4 mm / +6 mm) match the OEM geometry exactly, so the steering geometry is preserved while suspension compliance and control are dramatically improved. Traction under acceleration, composure mid-corner and feedback through the seat all improve noticeably — qualities that matter equally on a mountain pass and on circuit.

Fitment and Compatibility

This shock absorber is designed and validated specifically for the following motorcycle:

• Kawasaki Ninja 400 — model years 2018, 2019, 2020, 2021, 2022, 2023

Part number: 279S-018-150-005

Installation should be carried out exclusively by an authorised K-Tech Service Centre. Specialist tooling and technical knowledge are required to achieve maximum performance and to ensure safe operation of the unit.

Specifications