K-Tech DDS Closed Cartridge Kit (+10mm) Yamaha YZF-R1 RN32, RN49, RN65 (2015-2026) 155-015-270-021

Upgrade your Yamaha YZF-R1's stock fork with a cartridge system trusted at the British Superbike Championship and the Isle of Man TT — yet equally rewarding on everyday road and track-day use. The K-Tech DDS Closed Cartridge Kit (+10mm) replaces the factory internals with a precision Direct Damping System that delivers consistent, fully adjustable damping wherever you ride, without the unpredictability of a standard open cartridge.

Key Features

• Direct Damping System (DDS) engineered specifically for the YZF-R1 stock fork legs, retaining the original fork tubes for a straightforward installation
• Pressurised closed cartridge design with a 20 mm piston and 31 mm control pistons for high oil flow, dramatically reducing response lag and improving feel across all speeds
• Patented cavitation-elimination design ensures consistent damping performance whether you are navigating urban traffic or pushing hard on a circuit
• +10 mm extended top caps provide the extra clearance needed for refined spring preload management
• 30 compression clicks of adjustment range, with suggested baseline settings of 16 compression clicks, 18 rebound clicks and 10 mm preload — making initial setup quick and accessible
• Supplied with three pairs of 36-260-series springs to suit a broad spread of rider weights and riding styles
• Proven at the highest levels of competition, including British Superbike and Isle of Man TT

Build Quality and Performance

K-Tech engineered the DDS Closed Cartridge Kit around a pressurised oil circuit that keeps the 20 mm piston in constant contact with a stable fluid column. The 31 mm control pistons allow a generous oil flow path, so the damping force tracks wheel movement faithfully rather than spiking under hard braking or mid-corner bumps. The 8 mm piston rod minimises offset inside the cartridge body, keeping friction low and the damping curve predictable whether the fork is moving slowly through a gentle undulation or reacting sharply to a kerb strike.

The patented cavitation-prevention geometry means there are no air pockets forming at high shaft velocities — a problem that causes the sudden loss of damping force felt as fork dive on standard cartridges. The result is a fork that behaves the same on lap twenty as it did on lap one, an advantage that matters as much on a long touring run as it does on a race circuit.

Everyday Usability and Value

Not every DDS Closed Cartridge Kit is built around track-only compromise. The three included spring pairs and the clearly defined baseline click settings mean a competent home mechanic can achieve a well-sorted road setup before ever visiting a suspension technician. The wide 30-click compression range then allows fine-tuning as your familiarity with the bike grows. K-Tech recommends final installation and initial setup be carried out by an authorised K-Tech Service Centre to ensure the cartridge is pressurised and shimmed correctly, protecting the investment and guaranteeing the warranty.

Fitment and Compatibility

This kit fits the following Yamaha models:

• Yamaha YZF-R1 RN32 (2015-2016)
• Yamaha YZF-R1 RN49 (2017-2020)
• Yamaha YZF-R1 RN65 (2021-2026)

Specifications