The rules do not say1 part
No boost article.
- Boost relief / overboost control valve · Forced induction
UIM · runabout
Runabout Veterans GP1
UIM 2026, 302.01.05. The rulebook does not state a governing principle for this class.
Read out of the published UIM rulebook on 2026-09-08, so confirm anything that decides a purchase. The full note is at the foot of the page.
Running the class
- Rider requirements
- Riders 40 or more years old under 302.01.05, or over 40 years under 302.01.07, which also asks for a minimum of one year's experience in a national or international championship.
- Riders on the grid
- 18.
- Championship status
- Continental Championship only - NOT a World Championship class.
Read from the same class section as the part answers. The rider side of the sport, tiers, ages, licences and what gets inspected, is set out across the bodies at Racing.
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 (71 parts)
4 permitted outright, 14 permitted with stated conditions, 52 left open by our reading of the class rather than by a quoted permission and 1 the rules do not settle. Grouped where the same rule gives the same answer, so two "Not legal" groups can sit side by side under different rules.
What each answer below means
- The rules do not say
- Unanswered. The rules do not settle this, so ask the club before you rely on it.
- Legal, with conditions
- Keep it, but measure it: the rules permit this part only inside stated limits.
- Legal
- Keep it. The rules permit this part in this class.
- No rule, this is an open class
- Probably keep it. The class carries no stock clause at all, so anything unlisted appears to be open. The rulebook does not say so in terms, and this is our reading rather than a permission anybody wrote down.
Legal, with conditions1 part
Free, EXCEPT the full circulating water type requirement on forced-induction craft. 502.04-07
- Aftermarket exhaust manifold / head pipe · Exhaust
Legal, with conditions1 part
Modified or aftermarket tanks permitted; filler neck outside the engine compartment. 502.04.02-08
Legal, with conditions1 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, with conditions1 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, with conditions1 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, with conditions1 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, with conditions1 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, with conditions1 part
Two rear sponsons are required, each at most 92 cm long, protruding no more than 100 mm, with a channel and a drop below the hull intersection of at most 63.5 mm each and a thickness over 6 mm; sponsons fixed inside the bond flange may not protrude outside it. 502.04.02-02
- Aftermarket sponsons · Hull and handling
Legal, with conditions1 part
Permitted. May not exceed the width of the planing surface or extend more than 100 mm rearward beyond the transom. All edges radiused. No fins, rudders or skegs. 502.04.02-05
- Aftermarket hull trim tabs · Hull and handling
Legal, with conditions1 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, with conditions1 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, with conditions1 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, with conditions1 part
Ballast of constant mass may be added within the normally exposed areas of the hull before competition to reach the 300 kg minimum, with no fluid ballast and no modification or relocation of other parts. 502.04-05, 502.04.02-07
- Ballast weight kits · Hull and handling
Legal, with conditions1 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 class35 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
- Supercharger internals, clutch and pulleys · Forced induction
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
GP1 prints no driveline article, and the titanium ban is written into GP2 only, so nothing in the class bars a titanium part. 502.04
No rule, this is an open class1 part
GP4 to GP2 require the reverse gate removed, but GP1 prints no driveline article, so removal is left to the builder. 502.04
- 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
No rule, this is an open class1 part
GP1 prints no article on work to the hull, so under its open-list reading a modified OEM hull is free while the craft stays within 360 cm long (394 cm for Endurance) and 127 cm wide. 502.04.01-03, 502.04.01-04, 502.04.01-05
- Modification of the OEM hull · Hull and handling
No rule, this is an open class1 part
No article limits an extension to the hull, so under the open-list reading of GP1 one is free inside the 360 cm overall length (394 cm for Endurance), and trim tabs may reach 100 mm past the transom. 502.04.01-03, 502.04.01-05, 502.04.02-05
- Hull extension · Hull and handling
UIM 2026, 302.01.05, read from the rulebook on 2026-09-08. Read the rule yourself, Runabout Veterans GP1. Every UIM class · where the rulebooks differ · how this site reads a rulebook.
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.
Cite this page
“Runabout Veterans GP1, UIM class rules”, BaddJet archive, https://baddjetarchive.com/legality/uim/runabout-veterans-gp1/
Add the date you read it.
71 parts read · 4 permitted, 14 with conditions · 2026 rulebook