OEM part required 3 classes
This class requires the OEM part.
- Fixed Steering Ski Stock · FSSK
- Four Stroke Ski Lites · FSKL
- Runabout Naturally Aspirated · RNA
IJSBA · Engine
Aftermarket or modified crankshaft assembly
IJSBA answers this part for 20 of its classes. 13 of those answers are permissions, with or without limits attached, and 7 are not.
Where it stands, class by class
20 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.
OEM part required 1 class
RRL.3.3
- Runabout Rec Lites · RRL
OEM part required 1 class
Crankshaft must remain stock. · SSK.3.2
OEM part required 1 class
RAS.3.3
- Runabout Stock · RAS
OEM part required 1 class
Crankshaft must remain stock in both displacement categories.
- Ski Modified · SKM
Legal, within limits 1 class
Rebuild only. 110mm rods and 60mm stroke ONLY. +/-5.00% assembly weight. Replacement counterweights must resemble the original. Non-ferrous prohibited.
- Vintage Ski Limited · VSKL
Legal, within limits 1 class
Rebuild with replacement counterweights, crank pins, bearings and rods; total assembly weight within +/-5.00% of OEM; NON-FERROUS crank components prohibited; stroke and rod length may NOT change.
- Ski Lites · SKL
Legal, within limits 1 class
Stroke and rod length may NOT change. +/-5.00% assembly weight. Non-ferrous metals prohibited.
- Sport Spec · none - this document uses ALL-CAPS section headings, not numbered rules
Legal, within limits 1 class
May be rebuilt or replaced provided counterweight shape, dimensions and material type, OEM stroke, rod length and journal diameters are retained; +/-5.00% assembly weight. · RAL.3.3
Legal, within limits 1 class
Two-stroke: stroke and rod length changeable. Four-stroke: +/-5.00% weight.
- Sport GP · SPGP
Legal, within limits 1 class
Variable stroke allowed so long as displacement limits are met; +/-5.00% weight.
- Runabout Open / GP · ROP
Legal 3 classes
Explicitly permitted by this class document.
- Vintage SC · VSC
- Vintage X2 · VX2
- Freestyle · FREST
Legal 1 class
Entire crankshaft assembly including connecting rods may be modified or aftermarket, total weight within +/-5.00% of OEM. · SKSS.3.6
Legal 1 class
RSS.3.2
- Runabout Superstock · RSS
Legal 1 class
Stroke and rod length may be changed. · VSK.3.4
Legal 1 class
Two-stroke: stroke and rod length alterable. Four-stroke: +/-5.00% weight.
- Ski Grand Prix · SKGP
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 IJSBA class · where the rulebooks differ · signed checks on parts the shop sells.
Engine · two and four stroke · legal outright in 13 of 20