OEM part required 8 classes
Must remain OEM.
- Runabout Endurance · W.2.3
- Runabout Lites · AA.2.2
- Four-Stroke Ski Lites · N.2.2
- Runabout GP2 · Y.2.2
- Runabout GP3 · Z.2.2
- Ski GP2 · L.2.2
- Ski 1100 Modified · R.2.2
- Ski 1500 Modified · Q.2.2
IHRA · Engine
Aftermarket or modified crankshaft assembly
IHRA answers this part for 29 of its classes. 6 of those answers are permissions, with or without limits attached, and 23 are not. 8 are inferred from how the class is written rather than quoted from a rule naming this part.
Where it stands, class by class
29 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.
Not permitted, not listed in the rules Our reading, not a rule we can quote at you. This class requires the craft to stay stock except where the rules allow otherwise, and this part is not on the list.
No rule, this is an open class Our 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.
OEM part required 4 classes
The OEM part may be modified. No aftermarket substitute.
- Drag, Yamaha Pro Stock · DD.1
- Drag, Sea-Doo Pro Stock · DD.2
- Drag, Yamaha Spec · DD.3
- Drag, Sea-Doo Spec · DD.4
OEM part required 1 class
Stroke and rod length modifications permitted. · T.2.2
OEM part required 1 class
Limits: weight tolerance 5 per cent. · K.2.2
OEM part required 1 class
Four-stroke above 1600cc must maintain the original stroke (V.4.2). Limits: weight tolerance 5 per cent. · V.2.2
Not permitted, not listed in the rules 4 classes
On a closed list an unlisted modification is not permitted. · A.2.2, J.1
Legal, within limits 1 class
No non-ferrous metals, stroke and rod length unchanged, counterweights resembling the original, and assembly weight within 5 per cent. · O.2.2
Legal, within limits 1 class
No non-ferrous metals, the Sea-Doo HX retaining its OEM unmodified 720 flywheel, and assembly weight within 5 per cent. · U.2.2
Legal, within limits 1 class
Model-dependent. On four-stroke entries counterweights, stroke and rod lengths remain as the manufacturer specified and weight stays within 5 per cent, and the source text is internally tense, see KB section 9 (BB.2.2). On two-stroke entries no non-ferrous metals, stroke and rod length unchanged, counterweights resembling the original with no added holes or pockets, and assembly weight within 5 per cent. · BB.3.2
Legal 2 classes
Limits: weight tolerance 5 per cent.
- Ski Vintage · S.2.2
- Runabout GP · X.2.2
Legal 1 class
Aftermarket permitted. · DD.5
No rule, this is an open class 3 classes
The class states only what it bans and calls itself run what you brung, against a section DD preamble that says anything unlisted is illegal.
- Drag, 2 Stroke Unlimited · DD.12
- Drag, Stand Up Unlimited · DD.10
- Drag, Unlimited · DD.6
No rule, this is an open class 1 class
No restriction in section CC, and CC.1 permits any modification it does not restrict.
- Freestyle · CC
Aftermarket or modified crankshaft assembly: 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 IHRA class · where the rulebooks differ · signed checks on parts the shop sells.
Engine · two and four stroke · legal outright in 6 of 29