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

John Moore has a longstanding involvement in event organisation and powerboat racing journalism. He organised the historic Cowes–Torquay–Cowes races between 2010 and 2013 and was actively involved with British offshore racing from 2017 until 2025.
In 2017, Moore founded Powerboat Racing World, a digital platform providing global powerboat racing news, insights, and event coverage.
He is now Editor of Powerboat.News, continuing to contribute to the sport’s media landscape with in-depth reporting and analysis.