Dear Personal Watercraft Racing Community,

The IJSBA is pleased to bring you this expanded explanation of the 2007 IJSBA Rule Book revisions.  The past three weeks have been spent discussing and following up upon the condensed rule changes posted on December 5.  These rule changes are the product of unanimous or majority votes of the IJSBA Board of Directors.  The Directors’ individual votes are products of the communication received from the interests which each board member serves.

This expanded explanation of the rule changes is being done in a narrative form in order to best give the motivation, purpose for, the limits of, and the reasoning behind each rule change.  Please consider each rule change individually and as part of a complete set of changes designed to better the sport of Personal Watercraft racing.  The IJSBA welcomes questions and comments regarding these rule changes.  If you have a comment or question, please make sure that you read the rule change carefully and that you have taken a moment to consider the rule change thoroughly.

1.   The IJSBA has voted to allow aftermarket hulls to compete in specific Ski and Runabout Open Classes.  The aftermarket hulls must adhere to the original Open Class rule requiring that the competing PWC be no more than 10% lighter than that particular PWC’s original OEM weight.  The allowance for aftermarket hulls is not extended to PWC that are homologated in amounts less than 500 units.

The IJSBA has voted to allow these hulls for various reasons.  The largest reason being that the contemporary Runabout hulls of today do not appear to be as closely matched to closed course racing as some of the hulls created in the mid to late 1990’s.  It is also the case that technology has allowed for greater performance out of most contemporary PWC power plants.  These two factors create a demand for hull modifications that will allow competitors to modify the handling characteristics of their PWC for those PWC to operate more safely in the closed course environment.  “Aftermarket hulls” will still continue to refer to the portion of the PWC below the bond line only. This is mostly a move to provide the greatest safety in the class with the highest performances.

There were numerous restrictions discussed as methods to prevent Open Class costs from severely escalating due to allowed hull modifications.  The idea for the hull allowance was to improve handling characteristics.  The IJSBA wanted to avoid a frenzy of expensive lightweight hulls in the carbon fiber and Kevlar varieties.  Therefore, the decision was made to not allow for any greater weight savings than was already allowed in open classes.  Some competitors may decide that they do not need any handling changes.  Those innovative persons who create handling packages that benefit particular PWC models are able to improve particular PWC in a less restrictive environment without the effect of starting spending wars.

The IJSBA is, at this time, not extending this hull allowance to any Runabout Classes besides the standard Open Class.  In other words, Runabout Veterans Open and Runabout 800 Open classes will not be allowed to use aftermarket hulls.  There is no apparent need for handling improvements in the 800 Open Classes.  Furthermore, there is no need to increase costs for the 800 Open Class when it is very well stabilized in its current condition.  In the Runabout Veterans Class, the IJSBA hopes to infuse the Four Stroke Limited Rules into Veterans Open classes rather than allow Four Stroke competitors to utilize Open Class modifications.  The reasoning here is that Four Stroke Limited Class prepared PWC appear to be well within the performance levels anticipated for a Veterans Class.  This, however, is a topic for 2008.

The IJSBA has received questions regarding the hull allowance for Amateur Runabout Classes.  Again, the IJSBA would like to reiterate that the primary reason for the aftermarket hull allowance in open classes is to allow contemporary OEM hulls to more safely compete in a closed course environment.  The IJSBA feels that such a safety measure must be extended to Amateur Classes.  During the years that the IJSBA offered Modified Class racing, the IJSBA extended the same Modified Rules to Novices ranks as it did to Expert and Pro ranks.  This uniform allowance reduces confusion and allows for Open Class PWC to be more easily sold and shared among team members.  The economy is currently too tight to expect the Personal Watercraft Racing Community to be able to bear the division of multi tiered Open Class rules.  Open Classes at World Finals will continue to be divided into Amateur and Pro.

The IJSBA has voted that PWC homologated under Rule 4.1.2.a (homologated units in quantities lass than 500) will not be allowed to utilize the allowance for aftermarket hulls.  The IJSBA has taken this precaution to prevent windfalls to those OEM manufacturers who may chose to produce limited quantities of ultra high performance PWC.  The reasoning here is, again, that the purpose of the hull allowance is to improve the safety of contemporary OEM hulls in a closed course environment.  If an OEM producer is producing a PWC in a low volume quantity then that producer shall not be eligible to enjoy the modification benefits intended for mass produced OEM hulls.  Simply put, if an OEM manufacturer is producing a low quantity “performance PWC” then that OEM manufacturer must furnish the hull, to the public, at the performance level that the OEM manufacturer wishes to see employed in a closed course environment.

2.  The IJSBA has voted to allow the Runabout Four Stroke Limited Class to utilize aftermarket jet propulsion pumps.

The IJSBA has voted to allow The Four Stoke Limited Class to utilize aftermarket jet propulsion pumps based on the factors of safety and ease and affordability of repairs.  Aftermarket jet pumps have been shown to allow more superior control (by means of reduced cavitation) in a closed course environment.  This allowance will reduce the potential for spin outs and collisions.  Further, it has come to the attention of the IJSBA that in the case of replacing a damaged jet pump, aftermarket pumps are often more affordable and/or easier to procure than an OEM replacement pump.  Therefore, consistent will all other Limited Classes, the IJSBA has added aftermarket pumps to the Runabout Four Stroke Limited Class.

3. The IJSBA has voted to increase the allowed sponson size allotments.

  The IJSBA has determined that the allowed depth for sponsons is grossly outdated as hulls have drastically increased in size.  The length of sponsons shall remain the same.  All Runabout Class sponsons will be allowed an additional inch of depth.  All Ski Class sponsons will be allowed an additional half inch of depth.

4.  The IJSBA has voted to increase the sound allowance for Runabout Open Classes to 100 db.

The IJSBA has been evaluating the sound restrictions for the Runabout Open classes during the last two World Finals.  During these events, the IJSBA had made an allowance for an increased db rate in the Pro Runabout class.  The responses to this allowance have all been positive.  The crowd response to the sounds of the Pro Runabout race was phenomenal.  Therefore the IJSBA shall make permanent a sound allowance of 100 db.  This allowance shall only apply to the standard Runabout Open Classes (these allowance do not apply to 800 Runabout or Veterans Runabout, etc.).

The IJSBA encourages all race directors to survey their local race sites to ensure that this expanded sound allowance is compatible with the venue.  If local regulations prevent such a sound increase then the race director may institute the same 86 db limitations that apply to all other classes.  If such 86 db limitation is in place then the race director or promoter must give adequate notice to all competitors.  Any notice greater than 20 days will be deemed adequate notice by the IJSBA.

5.  The IJSBA has voted not to remove the allowance for aftermarket ECU’s in stock classes.

The IJSBA has elected to continue allowing competitors to use aftermarket ECU’s in stock classes.  The IJSBA originally made the allowance for aftermarket ECU’s in Stock Classes due to the fact that there was rampart use of illegal aftermarket ECU’s (yes, it is true, some of you were cheating!!!) and it was impractical to have technical inspectors constantly checking for these illegal units that were nearly impossible to detect.  Today, illegal ECU’s are even more difficult to detect and their performance gains are more pronounced.  Therefore, the IJSBA has determined that removing the allowance for aftermarket ECU’s would not produce the results of performance and cost controls in stock classes because the ECU’s are likely to still be used.  Instead, the IJSBA will be controlling the effects of aftermarket ECU’s by the use of boost regulators.

6.  The IJSBA has voted to replace the remove Rule 6.4.8 (restrictor plates for Super/Turbocharged Stock Ski Class PWC) and require all Super/Turbocharged Stock Class PWC (Ski and Runabout) to utilize a boost regulator valve.  The IJSBA will require that these valves be set to open when the PWC reaches a boost pressure greater than 10% over the original OEM boost pressure of that model PWC.

The IJSBA has determined that the creation and procurement of limited quantity restrictor plates was not a practical or feasible solution for performance and speed controls in Ski Stock Classes.  Therefore, this requirement, set forth in Rule 6.4.8, has been removed.  This, by itself, would leave unaddressed the concerns that specific Ski Class PWC would be able to obtain unchecked performance levels and speeds that were not originally anticipated by a Ski Stock Class.  Especially crucial in this concern is the effects of an undetectable aftermarket ECU which has illegal characteristics.

The underlying problem is that when aftermarket ECU are applied to PWC with forced induction, the aftermarket ECU can easily be modified to control other components of the PWC in ways that are prohibited by the IJSBA Competition Rule Book.  The prime example of this problem is that an aftermarket ECU only may make aftermarket the original functions of that ECU (ie ignition timing, rev limits, etc.).  Were that ECU modified in such a manner that it sent a signal to the waste gate controller on a turbocharged unit which told the waste gate to open at a higher PSI than stock settings then that ECU would be making the waste gate an aftermarket product (aftermarket being defined as not functioning the same as an original counterpart).

Because the ECU changes may not be detectable, it is important to provide safeguards that prevent the undesired effects of aftermarket ECU’s.  As the key problem in aftermarket ECU is the undetectable ability to increase boost pressure, the key solution must be to control and prevent potential boost pressure increases.  This concern and solution applies to all forced induction PWC, both Ski and Runabout.  The IJSBA has been in heavy contact with PWC engine accessory manufacturers and OEM engine manufacturers who all have confirmed that this solution is practical, feasible, and affordable.  The IJSBA plans to have approved boost regulator valves widely available by March, 2007.  The IJSBA is planning on an effective implementation date of July 1, 2007 for this boost regulator requirement.

It is important to note that the purpose of this rule is twofold.  The main purpose, of course, is to curtail the effects of illegal properties of aftermarket ECU’s.  There is also the concern of controlling speeds and performances of Stock Class PWC.  This principle should be clearly understood.  The IJSBA is not and should not be in the business of building and designing PWC.  The speed and performance control concerns are not designed to control what an OEM manufacturer produces.  Rather, the speed and performance controls are designed to ensure that the OEM PWC that are prepared for Stock Class racing stay close to the OEM speed and performance parameters of the OEM PWC.  The stock class was originally designed to provide a close gap between showroom PWC and competitive racing.  Allowed modifications were for aesthetic (paint and decal), safety (seat grip, splash guard and foot well pads), handling (sponsons, steering systems, ride plates), and tuning (jetting, air filters, cooling lines, impeller) purposes only.  The allowance for aftermarket ECU’s was introduced as a fairness provision because select racers had access to illegally modified ECU’s which were not detectable.  This boost control provision reduces the effects of aftermarket ECU which are inconsistent with the original intentions of the Stock Class.

Again, the IJSBA is not and should not be in the business of designing OEM “stock” PWC.  The PWC Racing Community has fared quite well from innovative OEM producers who continue to set higher bars by constantly improving the quality and performance of their new model PWC.  Competitors fare well because they have a better quality product to work with.  Aftermarket accessory producers fare better because they have an improved format with which to create complimentary products.  Better improving products are natural in any line of goods and PWC is surely no exception as the performance improvements in PWC from 1997 to 2007 are as prominent as the improvements from 1987 to 1997.  The IJSBA does not intend (except perhaps in the rare occasion of some PWC produced in quantities of less than 500) to slow down OEM PWC in Stock Classes- we want to encourage OEM innovation, not stifle it.  It is well known  that slight manufacturing variances and legal tuning practices may yield RPM increases which will naturally increase boost pressure by small margins.  Therefore the IJSBA will allow a 10% buffer over the original OEM boost levels to account for increased RPM’s gained from legal impeller, fuel delivery, and cooling modifications.  The IJSBA will post a list of the OEM boost specifications of all homologated PWC that utilized forced inductions by March of 2007.

7. The IJSBA has voted to allow Two Stoke Normally Aspirated Ski Class PWC to increase their displacement size to a maximum of 850cc in all of the Ski Open Classes.

The IJSBA has determined that Two Stroke Ski Class PWC have further untapped performance ability than that which competitors are currently able to utilize.  In research conducted by the IJSBA along with OEM manufacturers, engine builders, racers, and aftermarket accessory manufacturers, it has been concluded that currently employed Two Stroke Ski Class PWC can gain performance improvements by increasing displacement up to 850cc with the OEM cylinders.  Research concluded that, after 850cc, the higher displacements would produce negative returns.

The IJSBA observed that Four Stroke Ski Class PWC made significant gains in performance improvement from 2005 to 2006 within the existing CC allotment.  Therefore, there is not a demonstrated need to increase CC allowances for any other Ski Class PWC than two stroke models.  The IJSBA reserves the right to make a mid season update by possibly allowing Stock Class and Limited Class Ski models to exercise displacement increases.  Competitors should not take this as a hint that the IJSBA will do so, only that we reserve the right to do so if it is determined that our efforts to unleash potential performance in the PWC which need it were needed in more classes.

8.  The IJSBA has voted to not allow displacement increases in Two Stroke Runabout PWC to be equal the displacement allowances for Four Stroke Runabout PWC.

The IJSBA had a great degree of discussion regarding the best way to extend the life cycle of the popular Two Stroke Runabout PWC in light of the rapid technical advances in Four Stroke Runabout PWC.  The IJSBA wishes to provide an environment where all PWC Competitors have a home that will allow them the continued enjoyment of their PWC.  It is clear that Two Stroke Runabouts have neared the end their life cycle as a consumer product.  There are only two 2007 two stroke runabouts being produced (GP1300R, 3D DI).  This does not mean that two stroke runabouts are at the end of their racing life cycle.  The IJSBA has kept Runabout 800 classes going despite the fact that those OEM units ended their production life nearly a decade ago.  Sport Class racing has been kept alive, and even recently rejuvenated, despite production on these units ending well before the 800 Runabouts.  There is no reason that Two Stroke Runabout Racing cannot be sustained for years to come.

Two Stroke Runabouts have been the forefront of expansive PWC racing due to a high period of growth and popularity in the proliferation of PWC ownership.  Over the last few years, these classes have experienced continued evolution in technology and rule allowances to allow these Runabouts to reach their full potential as competitive devices.  As the technology curve has ended on these PWC, so has the demand to create additional rules to push that technology to the limit.  The best protection the IJSBA can offer to this lineage of PWC is to stop the forward motion of rules expansion for these PWC and create permanent classes for the state these PWC will remain in from 2007 on.

What this means is opening up classes which recognize the classic and traditional nature of these classic Limited and Superstock forms of Two Stroke Runabouts and to keep those classes unchanged.  By creating Amateur Classic Runabout Limited and Amateur Classic Runabout Superstock, competitors who have significant investments in Two Stroke Runabouts can be assured that they will receive a long future of competing with like kind PWC even in the face of major advances in Four Stroke models.  Classic Runabout Racing is actually measured by a horsepower rating and dating system rather than a flat engine characteristic ruling.  However, the impact is to virtually separate two stroke PWC from Four stroke models (i.e. lower horsepower normally aspirated four strokes are likely to be allowed to compete in this classics class).

This path was chosen over a flat separation of Two Stroke and Four Strokes for various reasons.  The greatest of these reasons being that many Two Stroke competitors are still enjoying successes in their competitions in the classes where Two Stroke and Four stroke platforms are combined.  It did not seem like a smart idea to pull these competitors out of a class in which they wish to participate.  The next significant reason that Two Strokes and Four Strokes were not separated is that not all Four Strokes are incompatible with Two Stokes including some Four Strokes utilizing forced induction.  The real issue here is horsepower and performance potential from the OEM units.  Finally, there exists the potential negative outcomes of marketing Two Stroke Racing as a stand alone entity.

The planned permanent displacement allowances for the Classic Runabout Classes shall be OEM plus 250cc to a maximum displacement of 1350cc.  Eligibility for Classics Classes shall be set at the maximum OEM levels of 175 HP for Two Stroke models and 150 HP for Four Stroke models.  Eligibility shall also require that the PWC be at least three years old and is no longer in production or that the PWC has not been fundamentally changed in more than five years.  Eligibility into the Classics Classes is not automatic and shall be carefully considered by the IJSBA.  Superchargers and/or Turbochargers may not be added to any PWC in the Classics Classes.  These restrictions will ensure that Classic Runabout Classes remain a long time home for the great PWC that have been such an important part of the history of IJSBA racing.

9.  The IJSBA has voted to not allow engines to be interchanged between existing homologated models produced by the same OEM manufacturer.

The IJSBA has researched the matter regarding the requests to allow engine changes between existing homologated models produced by the same OEM manufacturer.  This provision currently exists in Modified Classes.  The IJSBA could find no significant and tangible results that could be derived from applying this provision to other classes.

10.  The IJSBA has voted to not extend membership to aftermarket engine producers for the purposes of allowing approved engine packages to be used as OEM replacement alternatives.

The IJSBA has been exploring the possibilities of allowing aftermarket engine producers to offer IJSBA engine packages to IJSBA competitors as an alternative to replacing competitors’ engines with only original OEM engines.  The IJSBA has seen great potential for updating existing PWC with newer engine packages that would result in drastic performance upgrades to those PWC competitors who need to replace an engine.  These packages appear to offer significant value for the dollar when utilized.  While the potential is very promising, the IJSBA feels there needs to be more time and research put into this endeavor before testing the feasibility of implementation of such a policy.

11.  The IJSBA has voted to allow tolerances in the thickness of replacement gaskets for stock classes.  Replacement base gaskets must not be thicker than 0.8 mm (0.032 in). Replacement head gaskets shall be allowed a tolerance of up to .005 mm (0.002 in) thinner than the original OEM head gasket and up to 1.5mm (0.06 in) thicker than the original OEM head gasket.  All other gaskets shall be allowed a tolerance of plus or minus 20%.

The IJSBA allows the replacement of OEM gaskets with those from replacement sources as a means of allowing competitors to make more convenient and affordable repairs to their PWC by not requiring that gaskets from only OEM sources be used.  Because replacement gasket manufacturers are not likely to perfectly replicate the OEM dimensions, the IJSBA has allowed slight deviations from the OEM dimensions.  Competitors should be fully aware that the IJSBA will enforce strict adherence to these expanded measurements.  It is the competitors’ responsibility to select replacement gaskets that fall within the allowances provided for in this IJSBA Rule Book.

12.  The IJSBA has voted to not limit the Inlet Hose/Air Filter Hose to 3.25 in ( 82.55 mm) interior diameter.  The IJSBA has voted to not require the Inlet Hose/Air Filter Hose to meet a temperature rating of 450 degrees Fahrenheit.

The IJSBA has researched the requested restrictions to the Inlet Hose/Air Filter Hose on competing PWC.  The IJSBA has found that the concerns relating to theoretical performance gains from oversized air inlet hoses do not overcome the burden placed upon aftermarket producers and competitors who have already created and used legal air intake systems created by adhering to published rules.  The IJSBA has determined that the former air inlet hose requirement that mandate the standards of USCG, UL-1111, or SAE J-1928 Marine is sufficient to protect against backfiring.

13.  The IJSBA has voted to add the following requirement to the Runabout Four Stroke Limited Rules: “Throttle Bodies must remain stock as supplied by the manufacturer.  No changing of throttle plate angles and/or modifications to the throttle body housing.  No Phenolic or Aluminum spacers are allowed behind the throttle body.”

The IJSBA has determined that the stock throttle bodies in all homologated Four Stroke PWC are sufficient to provide more than adequate flow to meet the power needs anticipated by the Runabout Four Stroke Limited Class.  Therefore, there appears to be no immediate need to allow modifications to the throttle body.

14.  The IJSBA has voted not to adopt the following language to Limited Classes and Four Stroke Limited Classes: “Replacement injectors are allowed providing the following: The number of injectors cannot be increased.  1 injector per cylinder.  Injector flow rating cannot exceed the OEM specifications of the manufacturer by more than 10%.  The number of orifices per injector cannot be changed (added or deleted).”

The IJSBA does not have sufficient test data as to the need for this rule or the impact of adopting this rule.  The IJSBA will continue to monitor  the progress of fuel injection as it relates to the performance of PWC.

15.  The IJSBA has voted to allow a Fuel Pressure Regulator to be added or modified for safety purposes.  This applies to Limited and Four Stroke Limited Classes.

The IJSBA has received requests regarding regulating fuel pressure for safety purposes.  While there have been no apparent needs for regulating fuel pressure, the IJSBA encourages all preventative safety measures.

16.  The IJSBA has voted to not require a belt guard on supercharged PWC.

The IJSBA has no evidence of a need for a mandatory belt guard for supercharged PWC.  As such, the IJSBA shall no institute this provision as a mandatory requirement.  The IJSBA encourages all preventative safety measures.  Therefore, the IJSBA shall not count any added belt guard as an illegal modification so long as it is determined that the belt guard modification is being used for only those purposes.

17.  The IJSBA has voted to not limit the inlet size of superchargers or turbochargers.

The IJSBA has received concerns regarding limiting the inlet size of supercharges and turbochargers.  The IJSBA has no test data to indicate that any particular size inlet will result in negative effects.  The IJSBA will continue to observe the progress of supercharger and turbocharger use in PWC racing and will implement control provisions if they become necessary.

18.  The IJSBA has voted not to allow Two Stroke Stock Ski Class PWC to utilize milled OEM heads.

The IJSBA received requests to allow Two Stroke PWC competing in the Stock Ski Classes to utilize milled OEM heads.  The IJSBA researched this request and has determined that there existed significant possibilities that milling the OEM head may result in negative performance gains in the closed course environment.  Further, such modifications would degrade the integrity of the stock class by stacking on further modifications that deviate from a perception of a “stock” PWC.

19.  The IJSBA has voted not to allow Two Stroke Stock Ski Class PWC to utilize aftermarket pump cones.

The IJSBA received requests to allow Two Stroke PWC competing in the Stock Ski Classes to utilize milled aftermarket pump cones.  The IJSBA researched this request and has received advice that such pump cones have little effect on a stock class PWC.  Since such modifications would degrade the integrity of the stock class by stacking on further modifications that deviate from a perception of a “stock” PWC, the IJSBA has opted to not vote in favor of this provision.

20.  The IJSBA has voted to not allow Two Stroke Stock Ski Class PWC to utilize backdated “bolt on” cylinders from other homologated PWC by the same OEM manufacturer.

The IJSBA received requests to allow Two Stroke PWC competing in the Stock Ski Classes to utilize backdated “bolt on” cylinders from other homologated PWC by the same OEM manufacturer.  The IJSBA researched this request and has determined that there may be some performance increases when particular OEM cylinders are applied to contemporary Ski Class PWC.  However, such specialized knowledge is not compatible with the philosophy of a Stock Class that is a close resemblance to a showroom PWC.  The backdating of rare and specific parts is counterintuitive of this goal.  Since such modifications would degrade the integrity of the stock class by stacking on further modifications that deviate from a perception of a “stock” PWC, the IJSBA has opted to not vote in favor of this provision.

21.  The IJSBA has voted to not remove the allowance for Four Stroke PWC to utilize aftermarket air filters in Stock Classes.

  The IJSBA has received a request to remove the allowance for Four Stroke PWC to utilize aftermarket air filters.  The IJSBA determined that there would be some slight performance decreases if the air filter provision was removed.  Even if the IJSBA were to adopt the philosophy that there is a need to enforce a small performance decrease in Four Stroke PWC, this method would add unnecessary inconvenience to the Four Stroke PWC competitors who have modified their PWC to the standards allowed by the IJSBA.  Further, air filters are the exact nominal performance upgrades that we would expect the same performance minded recreational PWC owners to make who would also be interested in experiencing Stock Class competition.  With these factors present, the IJSBA has decided not to adopt this rule change.

22.  The IJSBA has voted to allow the relocation of batteries, electrical boxes and other similar items for the purposes of installing aftermarket exhaust systems in the Limited Classes.

The IJSBA has reviewed requests to allow the relocation of batteries, electrical boxes and other similar items to allow for the installation of aftermarket exhaust pipes in the Limited Classes.  Such a provision has already been in place for the Open Classes.  Seeing as how Limited Classes and Open Classes normally use the same exhaust systems, the same platform of PWC that poses relocation needs will pose those problems to Limited and Open PWC in like fashion.  Therefore, the IJSBA has voted to extend this provision to Limited Class PWC.

23.  The IJSBA has voted to homologate all currently existing homologated Sport Class PWC on an international level.

The IJSBA has reviewed requests to grant complete international homologation to all existing Sport Class PWC that the IJSBA has homologated in at least some part of the world.  Specifically, this request involves international homologation of the Yamaha Waveblaster 800 and the contemporary Kawasaki X2.  Given that the IJSBA has renewed Modified Class racing for the Sport Class, there is less worry about an limited import PWC having a disproportionate advantage in Sport Class racing.  The IJSBA believes that this international homologation would have the only impact of increasing interest in Sport Class racing. Therefore, the IJSBA has voted to allow for this homologation.  The IJSBA would like to make it very clear that this international homologation of the contemporary Kawasaki X2 applies only to the general Sport Classes.  Nations that have specific X2 classes that separate the older X2 from the contemporary X2 need not include the two distinct PWC in the same classes.

Prepared by Scott Frazier, IJSBA managing director.