⟲ 360° — drag meThe facts.
| Part Number | 255-021-270-015 |
|---|---|
| Fitment | Yamaha YZF-R7 (2021–2026) |
| Body Diameter | 35 mm |
| Rod Diameter | 12 mm |
| Overall Length | 309 mm |
| Stroke | 55 mm |
| Piston Diameter | 32 mm |
| Spring Series | 55-155 |
| Upper Mounting | Fork | Width 25 mm | Bolt diameter 10 mm |
| Lower Mounting | Eye | Width 30 mm | Bolt diameter 10 mm |
DescriptionThe whole story▼
The K-Tech DDS Pro rear shock absorber for the Yamaha YZF-R7 (2021–2026) is a race-developed, British-made suspension unit that places professional-grade chassis control within reach of any serious rider. Proven in the British Superbike Championship and on the Isle of Man TT course, it delivers the kind of precise, repeatable damping that separates a truly dialled-in motorcycle from one that simply handles well.
Key Features
- Direct Damping System (DDS) technology with a reduced-diameter piston rod maintains stable, consistent damping performance across a wide temperature range — critical for both sprint races and endurance sessions.
- 32-mm piston allows exceptionally fine response sensitivity and broad adjustability, giving the rider meaningful feedback through every corner.
- 5-way adjustability covering compression, rebound, BPV (ByPass Valve), hydraulic spring preload and ride-height length — a complete geometry and damping toolkit in a single unit.
- 32 clicks of compression adjustment and 32 clicks of rebound adjustment enable micro-fine tuning to suit track surface, tyre compound and riding style.
- 16-click BPV (ByPass Valve) setting targets low-shaft-speed damping behaviour, refining corner entry stability and mid-corner balance with surgical precision.
- CNC-machined high-end components throughout for maximum dimensional accuracy and long service life under race loads.
- Integrated potentiometer mounting points support direct telemetry connection, enabling data-led suspension analysis.
DDS Technology and Performance
K-Tech's Direct Damping System places the damping circuit closer to the piston, reducing the lag that can occur in conventional shims-on-reservoir designs. The smaller-diameter piston rod keeps the effective damping area consistent as oil temperature rises during a long session, so the shock behaves on lap 20 exactly as it did on lap one. The 32-mm piston is notably large for a production-based shock of this class, and it translates into a wider, smoother adjustment range — no sudden steps between clicks, just progressive, predictable change.
Adjustability and Setup
The hydraulic spring preload adjuster allows rapid preload changes without tools — a genuine advantage during a practice session when rider weight, fuel load or circuit conditions change between runs. The length-adjustment facility lets the engineer dial in precise ride heights and steering geometry to suit track layout or individual preference, shifting weight distribution between axles with measurable accuracy. The recommended baseline settings — 12 clicks compression, 12 clicks rebound, 8 clicks BPV and 10 mm preload — provide a tested starting point from which riders can build their own bespoke setup.
Construction and Quality
Every DDS Pro unit is manufactured in the United Kingdom to the exacting tolerances demanded by the international race series in which K-Tech competes. CNC-machined aluminium and high-grade steel components are selected and assembled by hand, and each shock leaves the factory set to K-Tech's race-validated baseline. The 35-mm body diameter and 12-mm rod are dimensioned to balance stiffness against unsprung weight, keeping the suspension responsive to small road or track surface inputs without sacrificing structural integrity under hard braking or heavy kerbing.
Installation Note
For optimum performance and maximum safety, K-Tech recommend installation by an authorised K-Tech Service Centre. Professional fitting requires specialist tooling and a thorough working knowledge of suspension geometry. Incorrect installation may compromise handling and safety.
Fitment and Compatibility
Designed and dimensioned specifically for the Yamaha YZF-R7, model years 2021 to 2026. Upper mounting: fork type, 25 mm wide, 10 mm bolt diameter. Lower mounting: eye type, 30 mm wide, 10 mm bolt diameter. Always verify fitment against your specific model year and specification before ordering.
Specifications
| Specification | Value |
|---|---|
| Part Number | 255-021-270-015 |
| Fitment | Yamaha YZF-R7 (2021–2026) |
| Body Diameter | 35 mm |
| Rod Diameter | 12 mm |
| Overall Length | 309 mm |
| Stroke | 55 mm |
| Piston Diameter | 32 mm |
| Spring Series | 55-155 |
| Upper Mounting | Fork | Width 25 mm | Bolt diameter 10 mm |
| Lower Mounting | Eye | Width 30 mm | Bolt diameter 10 mm |
| Compression Clicks (recommended) | 12 |
| Rebound Clicks (recommended) | 12 |
| BPV Clicks (recommended) | 8 |
| Spring Preload (recommended) | 10 mm |
| RCU Adjustment Range | 5 mm |
| Country of Manufacture | United Kingdom |
FitmentWhich bikes this fits▼
- Yamaha YZF-R7 (2021–2026)
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