UIM · Exhaust
UIM answers this part for 16 of its classes, and publishes no rule for it in 8 more. 0 of those answers permit the part outright and 7 permit it with stated conditions, leaving 9 that do not. 5 are inferred from how the class is written rather than quoted from a rule naming this part. 8 are inherited from a parent class the rulebook points at.
24 classes, grouped where the same rule gives the same 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 borrow another class’s rules and are marked below; for those, the link to the parent class is read from the categories table rather than stated in the rulebook. 8 publish no rule for this part and name no parent to borrow one from, and are grouped together at the end.
OEM part required 3 classes
Ski GP3 is a two-stroke class, and 501.02.03.03 keeps its whole exhaust system as the manufacturer delivered it, so the original manifold and head pipe are required. · 501.02.01, 501.02.03.03
OEM part required 1 class
Two-stroke: the exhaust system must remain entirely of origin as delivered by the manufacturer. Four-stroke: Runabout GP3 has no exhaust article, so the manifold and head pipe stay stock under the class's own stock clause. · 502.02.03-03
Not permitted, not listed in the rules 5 classes
The class is four-stroke only and prints no exhaust article, so the original manifold and head pipe stay fitted under its own stock clause.
Legal, with conditions 3 classes
Free, EXCEPT that on forced-induction craft the exhaust manifold must be of the full circulating water type at all times when the engine is running. · 501.04.07
Legal, with conditions 2 classes
Two-stroke: allowed. Four-stroke: not specified, therefore stock.
Legal, with conditions 2 classes
Free, EXCEPT the full circulating water type requirement on forced-induction craft. · 502.04-07
No rule published for this 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.
Aftermarket exhaust manifold / head pipe: 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.
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Exhaust · two and four stroke · legal in 7 of 16 answered, all with conditions