Ski Stock

Listed below are the Ski Stock rules and rule changes for 2008. If it doesn’t say you can do it here then you cannot do it. It is your responsibility to read and understand these rules. The changes listed below are legal for EJSBA competition only. All boats must be completely stock as of the EJSBA Stock
rules.

Ski Stock:
The ratio between BHP and dry weight, claimed by the factory, must be not lower than 1:14 The final power of a Jet is determined by the ratio between the weight and the horsepower and not only by the horsepower, how to calculate the ratio: if the weight of a Jet is 160 Kg and the horsepower 140, you must divided 160 by 140, result is 1:14, if the weight is 132 Kg and the power 140 horse power the result is 1:06 so this is lower than 1:14, with this ratio you can not enter the “ Ski Stock class”.

Ski Stock:
All boats must be completely OEM (stock), with the exception of the following modifications:
• Jets (Carbs) and any OEM adjustable setting on the carbs
• Handlebars
• Handle pole
• Padding
• Trigger throttle
• Intake Grate
• Impeller
• Pump cover plate (ride plate)
• Bumpers
• One pair of sponsons (must receive the agreement of the Tec Director)
• Aftermarket bilge system
• Start engine and bendix
• You can use aftermarket a “primer kit”
• You can bore your cylinders but only use OEM oversize pistons
• Crankshaft may be rebuilt using OEM parts only.
• Any valves used within the entire cooling system must be OEM.
• Quick-turn steering modifications to alter steering ratio are allowed.
• Aftermarket steering cables will be allowed.
• Aftermarket water hoses and fuel line can be use as long as the inside diameter has the same dimensions as its OEM counterparts

Four-Stroke:
• ECU must be OEM for 4 stroke boats, with the OEM boost pressure.
• The EJSBA has the right to interchange one OEM ECU to another on all 4-stroke boats.
• The EJSBA is permitted to fix a boost pressure manometer or regulator before the start of the race on any/every boat they wish to.

Two-Stroke:
• Factory Pipe SXR air temp bypass is allowed.
• You can remove the choke butterflies from the OEM carburettors.
• Aftermarket ECU’s or ignition box are allowed for all 2 strokes. Yamaha SuperJet/ SuperJet RR rules for Stock class
• Yamaha Europe has asked us to update the SJ to the SJ RR and we have agreed.
• Every owner of a standard Super Jet 701, old or new model, can now update their boat to SJ RR model 2006 spec. You will now be allowed to run the cylinder, piston kits, cylinder head and gaskets from the 760 “RR” specification. We will also allow the use of Rius Racing hull extensions and the use of any aftermarket exhaust systems.
• If a new model of the Yamaha SJ RR comes out in 2008, you will only be allowed to update your old SJ to the new spec in 2009.
• The 760 cylinder, piston kits, cylinder head and gaskets can also be used in the Limited class.