UIM F1H2O Rule Updates – Final Extension for Mercury 2.5 EFI

The UIM Council has approved four significant rule updates for F1H2O, set to take effect from 1 January 2026. These changes reflect evolving priorities in sustainability, fairness, and race integrity. The proposals were introduced by the F1 Committee with support from COMINTECH and other technical bodies.


🏆 New Award for 4-Stroke Competitors

A new clause in Rule F1 7.14 introduces a special award for the highest-placed driver using a 4-stroke engine — provided at least 25% of the field competes with alternative engines.

This initiative aims to:

  • Encourage adoption of lower-emission technologies
  • Recognise competitive efforts using sustainable power units
  • Promote development of 4-stroke platforms across manufacturers

This award will be separate from the overall championship classification and underscores UIM’s commitment to environmental innovation.


⚖️ Equipment Weight: Minimums Clarified

Rule F1 8.5 has been updated to confirm minimum boat weights across all engine categories:

Engine Type
Minimum Weight
2.0 litres
486 kg
2.5 litres
550 kg
3.0 litres
586 kg
3.5 litres – 4-stroke
600 kg
4.6 litres – 4-stroke
600 kg (to be reviewed)

The clarification supports consistent scrutineering and competitive balance. Weighing procedures remain unchanged — the top six boats will continue to be weighed after time trials and races, with results not subject to protest.


🔧 Engine Homologation: Final Extension for Mercury 2.5 EFI

Rule F1 8.24.12 confirms that UIM homologation for Mercury Racing 2.5 EFI two-stroke engines is extended until 31 December 2026.

A one-year optional extension to 2027 may be granted following consultation with COMINSPORT under Rule 506.01. This will be the final permitted extension.

The decision balances:

  • Continued support for existing fleets
  • A clear transition timeline toward alternative engine platforms
  • Manufacturer certainty for development planning

🚩 Penalties: Buoy Destruction Fines Increased

Rule F1 11.6 has been amended to increase fines for destroying course buoys — both during and outside of races:

Infraction
Previous Fine
New Fine
Destroying first buoy
€600
€1,000
Destroying second buoy
€600
€1,000
First buoy destroyed during race
1 lap + €600
1 lap + €1,000
Second buoy destroyed during race
Disqualification + €600
Disqualification + €1,000

This adjustment reflects growing concern over race disruption and course integrity. Organisers and teams are encouraged to reinforce driver precision and awareness during competition.


Source: UIM Council / Powerboat.News