The rules do not say1 part
No boost article.
- Boost relief / overboost control valve · Forced induction
UIM · runabout
Runabout Veterans GP1
UIM2026, 302.01.05. The rulebook does not state a governing principle for this class.
Places where the rulebook contradicts itself, or where a figure could not be settled. Nothing in this list is decided, and it sits here rather than in a footnote because it is what you would want before spending money.
- Whether Veterans riders must additionally hold a GP1 Superlicence is not stated.
- The one-year experience requirement is stated in the Jet Raid/Offshore/Endurance article; whether it governs the circuit class is unclear.
What the rules say (68 parts)
18 permitted outright, 48 answered by our reading of the class rather than by a quoted rule, 50 the rules do not settle. Grouped by the answer, because an open class gives one answer to most questions and printing it once per part would say the same sentence forty times.
No rule, this is an open classOur reading, not a rule we can quote at you. This class carries no stock clause at all, so anything unlisted appears to be open. The rulebook does not say so in terms.
The rules do not say1 part
Not restated for GP1.
Legal, within limits1 part
Free, EXCEPT the full circulating water type requirement on forced-induction craft. 502.04-07
- Aftermarket exhaust manifold / head pipe · Exhaust
Legal, within limits1 part
Modified or aftermarket tanks permitted; filler neck outside the engine compartment. 502.04.02-08
Legal, within limits1 part
Legal ONLY when the craft is entered in Jet Raid, Offshore or Endurance. It must be fixed at the surface of the hull, and filling into an internal cavity of the hull is prohibited. 318.14
Legal, within limits1 part
Must fit the OEM battery box and be securely fastened. GP2 additionally allows relocation of the battery, box or housing limited to the strict minimum needed to fit an aftermarket exhaust.
- Replacement battery · Electrical
Legal, within limits1 part
BOTH turbocharging and supercharging on four-strokes, capped at 2000 cc. Water-jacketed housing and manifold required. NO BOOST LIMIT IS PUBLISHED. 502.04.01-01c, 502.04-07
- Aftermarket turbocharger or supercharger · Forced induction
Legal, within limits1 part
Max 100 mm beyond THE END OF THE PUMP ITSELF - a different measurement from the lower classes' 177.80 mm plate dimension. 502.04.02-04
- Aftermarket pump cover plate / extension · Driveline
Legal, within limits1 part
Full-length type with at least one bar parallel to the drive shaft, all leading edges radiused, extending no more than 12.00 mm below the flat plane of the pump intake area. GP1 adds that the projecting member must be filed so as not to create a hazard.
- Aftermarket intake grate · Driveline
Legal, within limits1 part
Identical, plus the bond-flange protrusion clause. 502.04.02-02
- Aftermarket sponsons · Hull and handling
Legal, within limits1 part
Same limits. 502.04.02-05
- Aftermarket hull trim tabs · Hull and handling
Legal, within limits1 part
Prototypes expressly permitted via the UIM logbook. The 50-specimen threshold does not apply. 500.02.02, 502.04-08
- Aftermarket or prototype hull · Hull and handling
Legal, within limits1 part
Aftermarket, modified or PROTOTYPE seats permitted. Must respect the structure and measurements of those available on the market for pleasure-navigation homologated PWC. The base must be well consolidated as it is the divider between the engine compartment and the seat. Seat height may be modified up to 10% from the original model. Back rest height max 18 cm with rider seated. 502.04.03
- Aftermarket seat assembly or seat base · Hull and handling
Legal, within limits1 part
Replacement bumpers allowed. A soft flexible water-spray deflector may attach to the hull sides or bond flange, not exceeding the perimeter of the original bumpers or the external hull edge measured with a plumb line. SAFETY BUMPERS ARE COMPULSORY in both GP1 classes.
- Replacement bumpers and water-spray deflectors · Hull and handling
Legal, within limits1 part
Same. Ballast may be added prior to competition to meet the 300 kg minimum. 502.04.02-07
- Ballast weight kits · Hull and handling
Legal, within limits1 part
All cooling system valves must be of FIXED OR AUTOMATIC type - thermostats, pressure regulators, solenoids. Manually controlled devices that alter cooling water flow while under way are prohibited in every class, as are electronic water injection systems unless of origin.
Legal1 part
Aftermarket spark plugs of a different heat rating are allowed in every class that addresses them.
- Aftermarket spark plugs of a different heat rating · Electrical
Legal1 part
Free within the GP1 seat article.
- Aftermarket seat cover · Hull and handling
Legal1 part
Padding and mat kits may be added and custom painting is allowed. Metal components above the bond flange may be polished, shot peened or painted.
- Padding, mat kits and custom paint · Hull and handling
Legal1 part
Cooling system flush kits are allowed in every class that addresses them.
- Engine flush / rinse kit · Cooling
No rule, this is an open class34 parts
No article covering this part. Free under the open-list reading of GP1.
- Through-hull exhaust outlet flap removal · Exhaust
- Carb jet kit, needle valve, needle valve spring · Fuel
- Aftermarket or modified rotary valve · Fuel
- Aftermarket intake manifold · Fuel
- Aftermarket flame arrester / air filter · Fuel
- Ducting between flame arrester and throttle body / compressor · Fuel
- Aftermarket crankcase vent catch-can / blow-by oil system · Fuel
- Aftermarket electric fuel pump · Fuel
- Aftermarket fuel filler cap · Fuel
- Aftermarket vapour / air separator · Fuel
- Aftermarket or modified throttle body · Fuel
- Aftermarket CDI / ignition box (2-stroke) · Ignition
- ECU reflash / software reprogramming · Ignition
- Aftermarket flywheel or alternator (2-stroke) · Ignition
- Aftermarket charging system / stator · Ignition
- Aftermarket cylinder (2-stroke) · Engine
- Aftermarket cylinder head (2-stroke) · Engine
- Aftermarket piston assemblies · Engine
- Crankshaft rebuild components (counterweights, pins, rods, bearings) · Engine
- Aftermarket valve springs, washers and retainers · Engine
- Aftermarket valves · Engine
- Aftermarket head gasket · Engine
- Port chamfering service · Engine
- Replacement engine mounts / engine bed · Engine
- Replacement starter motor and bendix · Electrical
- Aftermarket impeller · Driveline
- Replacement wear ring · Driveline
- Aftermarket pump/impeller housing, stator vane assembly, pump plate, pump shoe · Driveline
- Aftermarket pump nozzle and directional nozzle · Driveline
- Aftermarket driveshaft, couplers, bearing housing · Driveline
- Aftermarket nozzle trim system (pump-mounted) · Driveline
- Aftermarket switches and switch housings · Electrical
- Aftermarket bilge draining system · Hull and handling
- Aftermarket cooling lines, bypass systems and fittings · Cooling
No rule, this is an open class4 parts
No article.
- Aftermarket waterbox · Exhaust
- Aftermarket or modified carburettor · Fuel
- Aftermarket fuel injection system · Fuel
- Aftermarket reed valve assembly · Fuel
No rule, this is an open class3 parts
No engine article.
No rule, this is an open class1 part
No exhaust article at all, so the same open-list reading applies here as in Ski GP1.
No rule, this is an open class1 part
No ignition or electronics article.
- Aftermarket standalone ECU · Ignition
No rule, this is an open class1 part
Not specified; free under the open-list reading.
- Aftermarket intercooler · Forced induction
No rule, this is an open class1 part
Not restated.
- Reverse gate removal · Driveline
No rule, this is an open class1 part
No hood article.
- Aftermarket hood · Hull and handling
No rule, this is an open class1 part
No steering article.
- Aftermarket steering shaft, holder, handlebar holder, cables · Hull and handling
No rule, this is an open class1 part
Padding requirement not restated.
- Aftermarket handlebars, throttle, cable, grips · Hull and handling
UIM 2026, 302.01.05, read from the rulebook on 2026-09-08, not verified by a racer. Read the rule yourself, Runabout Veterans GP1. Every UIM class · where the rulebooks differ.
This is one class. Every part below also has a page of its own showing where it stands across every class this body runs, and legality by part is the index of them.
68 parts read · 18 permitted outright · 2026 rulebook