UIM · Hull and handling
The highest-stakes eligibility question, and UIM's answer is binary.
UIM's production threshold is 50 units against IJSBA's 500. A small-builder hull can clear UIM homologation and fail IJSBA's outright.
24 classes, grouped by the answer rather than listed one by one, because an answer that holds for a class usually holds for every class that borrows its rules. 8 of them publish no component rules of their own and are marked below; for those, the link to the parent class is read from the categories table rather than stated in the rulebook.
Not legal 9 classes
Explicitly prohibited by this class.
Not legal 2 classes
Homologated production craft only - 50 specimens, marketed, conformity certificate.
Governed by the parent class 8 classes
No component rules are published for this class and no single parent class is named, so this part cannot be answered for it. That is an absence in the rulebook, not a permission.
Legal, within limits 3 classes
PROTOTYPES EXPRESSLY PERMITTED via a UIM-issued logbook, valid 4 years, presented at every event. GP2 and GP3 homologated craft are also eligible. · 500.02.02
Legal, within limits 2 classes
Prototypes expressly permitted via the UIM logbook. The 50-specimen threshold does not apply. · 500.02.02, 502.04-08
Aftermarket or prototype hull: if the rule your class applies reads differently to you, or the rulebook has changed since this was read, ask. We answer with the section we read it from, or that we have not read it. Ask a rules question.
Every UIM class · where the rulebooks differ · signed checks on parts the shop sells.
Hull and handling · two and four stroke · legal outright in 5 of 24