H2O Performance Water Radiator Kit – Yamaha R6 RJ15 (2008–2016)

The Yamaha R6 RJ15 is one of the most focused supersport machines ever built — and H2O Performance has spent years refining cooling solutions that match that ambition. This water radiator kit replaces the factory unit with a high-performance core engineered for greater surface area, optimised fin geometry and superior heat dissipation, giving your R6 the thermal headroom it deserves whether you are pushing hard on a track day, carving mountain passes or commuting in summer heat.

Key Features

• Significantly enlarged cooling surface compared to the OEM radiator, allowing far greater heat transfer at all engine speeds
• Optimised fin geometry maximises airflow efficiency and draws heat away from the coolant more effectively under sustained load
• Stable coolant temperatures even at full throttle in high ambient heat, reducing thermal peaks during extended sessions
• Reduced heat soak and engine wear — the motor consistently operates within its ideal temperature window, protecting internals over the long term
• More consistent power delivery across the entire rev range, with improved throttle response when the engine is properly cooled
• Direct OEM replacement — precision fitment for the R6 RJ15 chassis means straightforward installation with no modification required

Design, Finish and Heritage

H2O Performance has built its reputation supplying cooling upgrades to road riders and race teams alike, and the craftsmanship shows in this kit. The radiator core is constructed for durability under repeated thermal cycling, with robust construction that stands up to the punishing demands of both circuit work and hard road riding. The clean, purposeful appearance sits naturally behind the R6 fairing — this is a component designed by people who understand what a high-revving supersport engine actually demands from its cooling system.

On the Road and the Circuit

The stock R6 RJ15 cooling system is adequate for moderate use, but it was never designed with sustained high-rpm track sessions or back-to-back track days in mind. Once ambient temperatures rise or lap times tighten, coolant temperatures climb, the ECU begins to protect the engine through fuelling adjustments, and the crisp, linear power the R6 is known for starts to soften. The H2O Performance kit resolves that constraint at source — more cooling capacity means the engine management system can work as intended, keeping every corner exit sharp and every straight clean.

What You Will Notice After Fitting

• More stable coolant temperature readings even under sustained hard riding
• Fewer thermal spikes during long track sessions or repeated high-speed runs
• Smoother, cleaner engine behaviour at operating temperature
• Improved power delivery across the full rev range
• Greater confidence in the reliability of the engine under demanding conditions

Fitment and Compatibility

This H2O Performance water radiator kit is a direct OEM replacement specifically designed and precision-manufactured for the following model:

• Yamaha R6 RJ15 — model years 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016

Specifications

• Brand: H2O Performance
• Type: High-performance water radiator kit
• Fitment: Yamaha R6 RJ15 (2008–2016)
• Core design: Enlarged surface area with optimised fin geometry
• Installation: Direct OEM replacement, no modification required
• Intended use: Road, touring and circuit / track day