Legal in every class. Same numeric envelope everywhere.
This page is IJSBA only, and the bodies do not
agree. The same part under IHRA and UIM. Which one applies to you is decided by whoever sanctions the race you enter.
This is one body's answer, not the sport's. You are bound
by whichever body sanctions the event you enter. If you race more than one
series, build to the stricter answer. The differences are set out in
the rulebook comparison.
Freestyle additionally accepts a horizontally-mounted grate with a minimum 40% of the intake area blocked.
20 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.
Keep it, but measure it: the rules permit this part only inside stated limits.
Legal, with conditions 18 classes
Full-length type with at least one bar parallel to the drive shaft, all leading edges radiused, extending no more than 12.00mm (0.47 in) below the flat plane of the pump intake area.
Full-length, with a bar parallel to the drive shaft and radiused leading edges. This document prints the same conflicting limit as Ski Lites, 11.00mm beside 0.47 in (about 11.9mm), so a grate built to 11.00mm passes under either figure; confirm with the inspector before the event.
Full-length type with at least one bar parallel to the drive shaft and all leading edges radiused. The depth below the flat plane of the pump intake area is printed as 11.00mm (0.47 in), and the two figures disagree, since 0.47 in is about 11.9mm. Build to 11.00mm, which passes under either reading, and ask the technical inspector which figure they enforce. · SKL.2.4
Four Stroke Ski Lites. Corrected 2026-10-04: the Four Stroke Ski Lites row gave 12.00mm, where its class document prints 11.00mm (0.47 in).
Ski Lites. Corrected 2026-10-04: the Ski Lites row gave 12.00mm, the figure most IJSBA classes print, where this class document prints 11.00mm beside 0.47 in.
Aftermarket intake grate: 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.