IJSBA is pleased to release the recommendations for changes to the 2024 IJSBA Competition Rule Book. These items will be submitted to the IJSBA Board of Directors, at 8:00 PM PST, on January 5, 2024.  This gives more than 24 hours for final comments.  These recommendations are based off of input received from the public in response to all compiled suggestions.  IJSBA will report the results of these voting items within 7 days from today.   Please send any questions or comments regarding these recommendations to info@ijsba.com


Managing Director’s Comments:  Some rule suggestions are difficult to make.  One, in particular, is the decision to recommend the adjustable cam timing gears in Stock Class.  There is a very sharp difference of opinion between many people on this subject.  To some, the allowance of the gear is the antithesis of Stock Class Racing and a regular comment received was : “well, at that point, why don’t you just allow a complete aftermarket camshaft?”  To others, the opinion is: “we are allowed to change the cam timing and it can be inconvenient and expensive to make the corrected timing change by constantly having to reposition the sprocket, it would be less hassle to have this adjustable gear.”  Conflicting opinions can both be valid.  In circumstances such as this, my recommendation was based on making already allowed modifications easier.  For 2024, I have tried to monitor the market evolution of specific categories of the sport while minimizing cost increases.  My recommendations are finalized after receiving as much input as possible from the racing public.  I try to vet these recommendations and develop them as works in progress.  By the time recommendations are finalized and sent to the Board of Directors, I have compiled a dossier of comments for the group to evaluate during voting.  I realize recommendations do not always reflect agreement of everyone.  I am personally grateful to everyone who has participated in this process.


Discussion:  Many comments were received regarding allowing excessive improvements in the Vintage Ski Class; while multiple submissions were made for the same suggestions, there was insufficient public support to recommend these changes.  A limited number of suggestions were recommended which seemed to be consistent with repairing and maintaining vintage hulls and/or allowing modern products to fit inside vintage hulls.  Removing 800cc displacement from Vintage X2 received no public support and was not recommended.  Many suggestions were received for provisions already allowed in the rule book.

Some very interesting suggestions were received that can best be implemented in race director guides at events and refined before major events.  After further refinement and practical evaluation, these suggestions can be codified in the Rule Book after post implementation review.





Recommendation:  Yamaha watercraft are allowed to affix either an OEM 760 Cylinder with larger dome to maintain compression ration OR a fully reprogrammable aftermarket ignition that maintains charging features.



Recommendation:  Allow aftermarket filler neck assembly with preference for repurposing OEM.


All SKI Categories: 

Recommendation:  Sponsons affixed to the inside of the bond line may be recessed above the bond line so long as a hazard is not created.


SKI Stock:

Recommendation:  Allow timing adjustment sprockets to be affixed to OEM camshafts.



Recommendation: Allow a boost increase of 3 psi to provide up to 11 psi for displacements under 900cc and 9 psi for displacements above 900cc.


Recommendation:  Allow aftermarket filler neck assembly with preference for repurposing OEM.

Recommendation:  Aftermarket splash guards on or integrated into the upper deck or hull may not extend past the bond line effective September 1, 2024.

Recommendation:  All hulls/top deck must approved and cataloged by October 1, 2024




Recommendation:  Allow blow off valves to be used to preserve engine life.




Recommendation:  Allow hull inner liner to be modified so long as exterior of hull conforms to legal specifications (i.e. with 2mm of OEM).  Floatation foam may be aftermarket or modified so long as flotation properties are maintained.

Recommendation: Allow bulk heads to be modified.

Recommendation:  Allow fuel filler to not be restricted to OEM so long as the replacement filler comes from another OEM homologated watercraft.

Recommendation: Allow for flywheel covers to be modified or aftermarket.

Recommendation: Allow for electrical components to be relocated.



Recommendation: Formally appeal changing designation of Amateur Freestyle to a displacement of 1200 cc and return it to 900 cc.

Action Plan:

IJSBA will observe the growth of Elite Junior categories in 2024 and discuss with Junior parents and organizers for viability.  Insufficient support was received to mandate these categories.

IJSBA will review suggestions based on impeding progress  throughout the year and prepare a comprehensive competitor guide prior to the 2024 SBT WGP-1 World Finals.

IJSBA will better police situations where winning competitors, at World Finals, are brought to the announcer podium for coverage so that fellow competitors can witness the chain of custody of all watercraft brought to impound.