COMPLETE UIM RULE BOOKhttps://www.uimpowerboating.com/Documen ... reader.pdf- SPORT OUTBOARDS....... S750 551 to 750 cc . -
HULL Only catamarans are permitted
- MINIMUM DIMENSIONS Class Weight Length
S 750 280 kg 3.90 m ——————
including driver, personal safety equipment, residual fuel but without residual water.
- MACHINERY An outboard motor is a mechanical propulsion assembly which can be removed from the boat as a single unit, complete with its transmission, and which does not transmit the power through the hull at any point. Any mechanism intended to modify the angle of attachment and/or the height of the motor is authorized. The motor thus taken off and placed ashore must be capable of being started, fed by its fuel tank. The mounting supports fixed to the boat, the control levers, the tachometer with its connections, the battery with its conductors and the fuel tank and fuel lines do not form part of the power unit. Only single motor is permitted. 543.02 To be homologated as a sports motor, an outboard motor must be sold and advertised by an industrial firm as being manufactured in standard production series (that is to say with all parts interchangeable and with identical dimensions and materials with the equivalent part in another motor of the same model.) for the propulsion of boats. A sports outboard motor must be able to run at a reduced speed. When the motor is in the water, the cooling must be effected by the homologated water circulation pump. An efficient gear changing system giving forward, neutral and astern movement is compulsory for motors up to and including 1000 cc capacity. The control handle for reverse gear, ready for use, must be within easy hand reach of the driver when he is in the normal driving position. Manoeuvring of the boat astern must be possible by selecting reverse gear. The casing of the underwater unit (gearcase) is free. All internal parts referred to on the homologation file must be maintained. Should the homologation provide for it, the exhaust will be a propeller exhaust. 181 2017 Circuit Rules Published on 23/12/16 543.06 All lower unit exhaust openings must remain standard within the homologated size. 543.07 For motors 1001 cc capacity and above, forward, neutral and reverse gear are not compulsory. Such fixed gear versions are not necessarily intended for sale to or be used by general non-racing public. However, they must be available as an integral part of the complete outboard motor and homologated as such. The mounting brackets, midsection including exhaust pipes and gearcase, together with any parts required to fit these, must retain the dimensions specified on the homologation form. 543.08 An electric or manual starter must assure a quick and easy start without external aids. It must be used as it was supplied by the manufacturer, no adjustment or alteration being allowed. 543.09 -
SOLE MODIFICATIONS ALLOWED 1. All studs, screws, nuts, bolts and their washers are free as well as the method of locking them;
2. The original propeller may be replaced by another in accordance with 504.13.
3. The trim tab may be altered or removed to accommodate a propeller;
4. The cooling must be provided by the water pump;
5. Thermostats and pressure valves of the cooling system may be removed;
6. The steering mechanism may be altered. If the original steering bar is removed or new ones are installed, any openings created must be sealed to prevent the motor from pulling in additional air;
7. The swivel bracket may be altered for the purpose of installing a power trim and/or a power lift and the dampers (shock absorbers) may be altered or removed. For F4 class the standard power trim is allowed, the power lift is not allowed in F
8. The rubber mounts of the motor may be altered, removed or replaced;
9. Revolution counters, water temperature gauges, water pressure gauges and similar instruments, can be installed;
10. Revolution limiters may be removed;
11. The gear interlock device on the starter may be removed;
12. Spark plugs are free;
13. Original carburettor jets may be replaced for another size;
14. Springs may be added to the throttle lever of the carburettors;
15. Re boring is allowed, but only piston assemblies supplied by the manufacturer of the motor may be used within the cc limit of the class. When ports in cylinders are adjusted to the dimensions specified in the homologation sheet, material may only be removed in the specified opening to a depth of 10 mm, to match the shape of the original adjacent connecting passage (channel) outside the adjusted port opening. This also applies to other openings in the motor for which the dimensions are specified in the homologation sheet; For classes using Mercury 2.5 EFI homologation sheet n° F-1/00496 (F1 engine) the use of aftermarket pistons and connecting rods is allowed, conforming to UIM homologation specification. The number of piston rings must be the same 183 2017 Circuit Rules Published on 23/12/16
16. A part which is dimensioned in the homologation sheet may be machined for the purpose of reaching that specific measure;
17. A part may be machined to attain the weight quoted in the homologation sheet without altering other criteria given for the part in question. It is not allowed to change the flywheel but balancing machining is allowed if the dimensions and weights provided for on the homologation sheet are respected;
18. Measurements not quoted in the homologation sheet shall only be checked by visual comparison with standard parts. As the actual manufacturing tolerances are not published, small differences between the inspected part and the reference part must be accepted;
19. The fuel connector in the lower cover may be removed and the fuel hose from the fuel tank connected directly to the fuel pump. If this is done the opening left after the connector and around the fuel hose must be sealed to prevent extra air entering inside of cover; 20. Electric fuel pumps may be added provided the fuel still runs through the original fuel system and no parts are removed or blocked off;
21. No parts may be added to the motor unless specified in this rule;
22. It is allowed to extend the starter cord of a rewind starter so that the starting handle can be reached from the cockpit.