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Forgot to add that the Evo Cylinder Kit, $ 129.00, that turns a standard S-254 into a Evo series....will fit the stock Zenoah 260 as well. Seems like a no brainer if it was legal?!

J. Pflueger
 
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I realize that making rules and communicating these rules can be a difficult and thankless task.

That being said - Has anyone given any thought to what will happen in a couple of years when Zenoah and Sikk update their engine designs and put them on the market?

How will it be determined whether or not the updated engines are legal?

How likely would it be that Zen or Sikk would continue to produce the old design, and continue to supply spare parts for the old version? Carrying double the inventory for parts these days may not be financially supportable for very long for these companies.

Does the IMPBA have better way of getting the word out on engine rulings? - other than "accidentally" reading about on the IW Forum?

Should a Thunderboat racer just assume that he may need to invest in a new engine every couple of years or so, depending on what develops between the rule making process and the manufacturer's advancements?



Yes very well said.

But as Don and Mike have said, and i havent heard anyone else in authority, Because RCMK, IMPROVED THEIR MOTOR, and its not on the IMPBA approved motors List. They are final, they are the written rule amd what they say we all must comply.

So if its not legal, Whats the step to GET IT LEGAL??

Steak & CHampane dinners, Take Mike to the local Gentlemans club, to help him *Tech* the motor, invite Don & Mike along with their families to a weekend in Vegas? WHAT????

I may not agree with either one of them, because RCMK, just improved their cylinder timings ever so slightly and the motor is still the S-254 design, but whats it gonna take for or IMPBA appointed Technical Review person to review the motor and make his recomendation?

Sorry,(IMHO) the current IMPBA B.O.D is not helping this hobby or its membership, when boat hull,electronic, or motor technolgy is improving and going forward, and we cant seem to determine if its legal, or is allowed.

Do all the new boat hulls, mono, hydro, thunderboat,etc.etc, have to be put before some Tech committe before its allowed to participate in IMPBA sanctioned events?

I see all these generations, 1,2,3 so on and on, of sport hydro,mono etc. are these approved? Everytime some hydro builder improves their sponson design, or a new prop is made avaliable, does it have to be approved?

Was the 2.4 GHZ radio go thru Tech approval,If it did, im not able to find it in the current rule book.

What would be nice if Mike would explain just what was so different about the S254 evo motor that has deemed it illegal, or confere will B.O.D since this motor was released after their once a year meeting.

Im sure some may not like what i have said, to make ALL happy, and maybe understand just what our IMPBA Technical Director is for, explain or give us a fix on this RCMK EVO motor so the ones that want to buy it and try it out can do so.

Bob Morrow
Any time you want to bend the rules all you need to do is put it on the race flyer. If we dont stop all this soon we will just have 2 sport hydro classes. Is there an answer there are many,the solution just needs to be one that keeps the class alive and healthy. Maybe we should change the rules to any 27 motor even just drop the super sport rules in the trash. These boats were not supposed to be 60 mph monsters but are headed that way.
Hey Mike,

I think you can say that about alot of racing venu's ie. Unlimited Hydro's, Indy cars etc. You just can't hold technology back....it's gonna find a way. Nice seeing you on the vid's at Hobart.

J. Pflueger
 
I am probably stating the obvious here - but I'm guessing that the EVO engine was outlawed in order to not obsolete all the Zen and Sikk powered thunderboats that are already out there. Let's face it, there are more of those out there now than the EVO powered boats. I suspect there are dozens if not hundreds of Zen and Sikk powered thunderboats out there already. So from that perspective - the ruling makes sense. It causes no harm to the largest group of members (in the short term).

Going forward - I wonder if it would be possible to negotiate with the Zenoah and Sikk producers to promise to "freeze" the current design for, say, five years. That's what the Indycar rule makers have done, and it has greatly reduced costs for the teams. The "design freeze" would give boat racers the confidence that they could get into this class and not be faced with major engine expenses for five years. I think that that could really help the class out, so it could establish a foothold, and flourish. And this would also keep the Thunderboat's original appeal of being a "low-cost-scale-like-round-nose" event, which appeals to a lot of boaters.
 
For $129.00 those models, Zenoah, etc., can be updated to EVO standards. There's a kit to do this on gizmomotors.com. Not a bad upgrade of 1 1/2HP and technology for the money on an older motor. I've looked, seen and read the differences between the approved and not approved S-254 and the majority of the upgrades had nothing to do with performance. The EVO should be allowed for sure.

J. Pflueger
 
Below is a copy and paste from a friend of mine over on JRCBD. It will provide some interesting reading.

POST FROM JRCBD:

It seems there is some confusion among the IMPBA members and some of the IMPBA Executive Council (EXC) about the Engine Specifications of the Super Sport and Thunderboat class that were voted in by the IMPBA membership. I have researched the paper trail and offer a few information comments. This has taken a considerable amount of my time on this great Saturday morning and I hope that Jim’s BD will not close this post. It is ment to be a somewhat read only post without all the usual flaming. If you want to flame me, do it offline at [email protected] It seems that a lot of people ask a lot of questions and flame others without first reading the rule book or other good info on the IMPBA Web Site. I suggest you read every Roostertail and the Minutes of all the EXC meetings.

1. Open the IMPBA web site http//www.impba.net and scroll down to Rule Book, scroll down to Large Gas I, scroll down to Super Sport Class item 3. Engine Specifications which describes a Super Sport engine. NOTE: There is no reference to engine manufacturer other than in the carburetor section.

2. Go back to the IMPBA web site, click on Roostertail, then on December 2008, scroll down to page 6 Thunderboat rules, reference engine selection limited to Zenoah or CY (SIKK) motors. This really surprised me as unlike NAMBA I have never seen IMPBA limit an engine to a specific manufacturer (MFG). I think this enters the field of “TRADE RESTRICTION”.

3. Go back to IMPBA web site and click on Roostertail, click on March 2009, scroll down to page 9, Ballot RE-Vote. EXC revised the wording of the Thunderboat rules.

NOTE: The reference to engine being limited to Zenoah or CY Sikk has been removed Ballot on page 47. OOPS looks like the EXC realized the mistake of limiting the engine to a specific MFG.

4. Go back to IMPBA web site, click on Roostertail, click on June 2009, scroll down to page 45, Gas Director’s report on new Thunderboat rule passing and a copy of the rule. NOTE: under engines specifications there is no reference to an engine MFG. This rule in now in effect for a two year period.

Zenoah has improved from a G-2DMarine to a 230 PUM, 231PUM and 260PUM and we did not ban the new models. The CY Sikk is much more powerful than the Zenoah 260 but we did not ban it. BAM!! Along comes a new, more powerful, less expensive engine, stock RCMK 254EVO from Korea.. The big flap starts about it being too powerful and unfair competition for the stock Zenoah and Sikk engines. The Technical Director now wants to ban the engine from the Thunderboat class. Saying it does not meet the “intent” of the class. I think we voted and passed the Thunderboat rules posted in the June 2009 Roostertail and they are locked in for two years. We did not vote on the “intent” of the rule. The definition of “Intent” varies from person to person and is very difficult to define.

What the Technical Director and the IMPBA EXC have to determine is does the motor meet the engine specification of the Thunderboat rules voted in by the IMPBA membership, and not the “INTENT” of the class.

Through the years I have seen Rossi come out with nitro engine that made the OPS and Picco somewhat obsolete and then OPS comes out with a PRO series that made Rossi, Picco and the older OPS engines somewhat obsolete. The IMPBA did not ban the new engines and the members had the choice of upgrading or not. I think we are now in that situation in the gas classes. The members will decide if they want to upgrade or run what they have.

I see comments that the “INTENT” of the Thunderboat class was a low cost, slow, gentleman class. Well folks competition somewhat kicked this in the behind. A competitive Thunderboat with a stock engine will cost $900.00 to $1,200.00 and if you have it built $1,500 to $2,000.00, They will average 50 to 60 MPH and approaching the first turn, the gentleman “INTENT” somewhat is forgotten.

I hope this paper trail of the THUNDERBOAT rules and personal comments have been of interest and I will mail a copy to each member of the IMPBA Executive Council (EXC).

Thanks for reading

Rip Holdridge IMPBA # 3899 Member since 1971. Hey I have raced against Ed Kalfus and John Bridge. Nope did not win.

__________________

Rip Holdridge

Carrollton (North
 
Well done Rip! I too just spent this afternoon going back and rereading this vote and proposals in Roostertails and it doesn't appear the specific motor issue was part of the final vote, at least I'm not seeing it............anywhere. This should be cleared up based on what was voted upon by IMPBA membership, nothing more or less. I really want to get into this class, now, but all who I have spoken to have said it's a mess with this engine rule thing. I for one thank you for your time.

J. Pflueger

IMPBA # 5XXX (I ran against Bridges and Kalfus too :) )
 
Below is a copy and paste from a friend of mine over on JRCBD. It will provide some interesting reading.

POST FROM JRCBD:

It seems there is some confusion among the IMPBA members and some of the IMPBA Executive Council (EXC) about the Engine Specifications of the Super Sport and Thunderboat class that were voted in by the IMPBA membership. I have researched the paper trail and offer a few information comments. This has taken a considerable amount of my time on this great Saturday morning and I hope that Jim’s BD will not close this post. It is ment to be a somewhat read only post without all the usual flaming. If you want to flame me, do it offline at [email protected] It seems that a lot of people ask a lot of questions and flame others without first reading the rule book or other good info on the IMPBA Web Site. I suggest you read every Roostertail and the Minutes of all the EXC meetings.

1. Open the IMPBA web site http//www.impba.net and scroll down to Rule Book, scroll down to Large Gas I, scroll down to Super Sport Class item 3. Engine Specifications which describes a Super Sport engine. NOTE: There is no reference to engine manufacturer other than in the carburetor section.

2. Go back to the IMPBA web site, click on Roostertail, then on December 2008, scroll down to page 6 Thunderboat rules, reference engine selection limited to Zenoah or CY (SIKK) motors. This really surprised me as unlike NAMBA I have never seen IMPBA limit an engine to a specific manufacturer (MFG). I think this enters the field of “TRADE RESTRICTION”.

3. Go back to IMPBA web site and click on Roostertail, click on March 2009, scroll down to page 9, Ballot RE-Vote. EXC revised the wording of the Thunderboat rules.

NOTE: The reference to engine being limited to Zenoah or CY Sikk has been removed Ballot on page 47. OOPS looks like the EXC realized the mistake of limiting the engine to a specific MFG.

4. Go back to IMPBA web site, click on Roostertail, click on June 2009, scroll down to page 45, Gas Director’s report on new Thunderboat rule passing and a copy of the rule. NOTE: under engines specifications there is no reference to an engine MFG. This rule in now in effect for a two year period.

Zenoah has improved from a G-2DMarine to a 230 PUM, 231PUM and 260PUM and we did not ban the new models. The CY Sikk is much more powerful than the Zenoah 260 but we did not ban it. BAM!! Along comes a new, more powerful, less expensive engine, stock RCMK 254EVO from Korea.. The big flap starts about it being too powerful and unfair competition for the stock Zenoah and Sikk engines. The Technical Director now wants to ban the engine from the Thunderboat class. Saying it does not meet the “intent” of the class. I think we voted and passed the Thunderboat rules posted in the June 2009 Roostertail and they are locked in for two years. We did not vote on the “intent” of the rule. The definition of “Intent” varies from person to person and is very difficult to define.

What the Technical Director and the IMPBA EXC have to determine is does the motor meet the engine specification of the Thunderboat rules voted in by the IMPBA membership, and not the “INTENT” of the class.

Through the years I have seen Rossi come out with nitro engine that made the OPS and Picco somewhat obsolete and then OPS comes out with a PRO series that made Rossi, Picco and the older OPS engines somewhat obsolete. The IMPBA did not ban the new engines and the members had the choice of upgrading or not. I think we are now in that situation in the gas classes. The members will decide if they want to upgrade or run what they have.

I see comments that the “INTENT” of the Thunderboat class was a low cost, slow, gentleman class. Well folks competition somewhat kicked this in the behind. A competitive Thunderboat with a stock engine will cost $900.00 to $1,200.00 and if you have it built $1,500 to $2,000.00, They will average 50 to 60 MPH and approaching the first turn, the gentleman “INTENT” somewhat is forgotten.

I hope this paper trail of the THUNDERBOAT rules and personal comments have been of interest and I will mail a copy to each member of the IMPBA Executive Council (EXC).

Thanks for reading

Rip Holdridge IMPBA # 3899 Member since 1971. Hey I have raced against Ed Kalfus and John Bridge. Nope did not win.

__________________

Rip Holdridge

Carrollton (North
The whole issue here is centered on whether the EVO is a legal SUPER SPORT MOTOR. At present time its not no sugar coating here Motor for Super Sport MUST BE APPROVED. Now again this motor can be used in LS27 with no problems.
 
Right now, there are three motors legal in stock form. All three motors are about the same price and produce about the same power. Some people won't be happy until the class is ruined which is what it will become if all engines are deemed legal. The Thunderboats are already going too fast for some brains to control...we don't need more speed...we need pretty boats. IMPBA is doing the right thing in policing which motors are legal in the class. Have fun with the class and stop bitching about it.

Brian Blazer
 
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Right now, there are three motors legal in stock form. All three motors are about the same price and produce about the same power. Some people won't be happy until the class is ruined which is what it will become if all engines are deemed legal. The Thunderboats are already going too fast for some brains to control...we don't need more speed...we need pretty boats. IMPBA is doing the right thing in policing which motors are legal in the class. Have fun with the class and stop bitching about it.

Brian Blazer
This seems to happen with almost every spec type class that is created...doesnt matter whether its NAMBA or IMPBA....stock OB, RTR, now possibly gas thunderboat...i want very much to purchase one of your kits for gas thunderboat, but once again it seems that i should wait again to see how expensive and high speed this class will become...god almighty isnt there enough classes out there for someone with deep pockets and the need for speed to play in?
 
I'm not waiting Bill, I'm jumping in :D . I think Brian's "Lauterbach" desisn is unbelievable. My intitial questions on engines have been cleared up and I'm going with a Zenoah. I'm really not looking for a "fast class" and as long as everyone's on the same playing field, I'm good to go! Hopeffully I can have this thing running next year. Thanks for everyones help and input.

J. Pflueger
 
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Bill we are seeing more of Brians boats down here they are gorgous and haul the mail
 
NOTICE!

The posts containing the name calling, abusive language and even a couple with threats of physical violence have been deleted. Any further posts on this thread of this nature will deleted and the person posting it will receive a lengthy time out from IW. Debates, even heated, on a subject are one thing one thing but this has gotten way out of hand so either keep it on the up and up or this thread will disappear and some may find themselves "on vacation".
 
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Straight out of the Thunderboat rules published in the June 2009 Roostertail page 45.

Super Sport Class

3. Engine Specifications

a. Each engine must have a working throttle control and the engine must be set up

to be completely stopped with the transmitter controls.

b. The engine must be a factory stock, commercially available piston ported fuel intake gasoline

powered 2-cycle engine with a maximum displacement of 1.647cid / 27.000cc. The cylinder

and head assembly must be a single unit (no removable heads and/or head buttons allowed).

Absolutely no internal modifications are allowed either by adding or removing material

to the engine. The originally equipped Carburetor (644 on Zenoah and 771 on the

Sikk) and/or Choke must be used as they came equipped from the Manufacturer of each engine

used. Some minor external modifications may be done but are limited to the following:

1) Tapping the case or carburetor heat dam for a water/cooling pump.

2) External modification to support a throttle linkage and or a kill switch.

3) Movement of the engine ignition coil to another location on the engine or hull.

c. The engine must use a spark plug type ignition. No glow plug or compression induced combustion

allowed. All engines must have a positive off-on switch, or in lieu of this switch, the

primary ignition lead must be removed from the spark plug except when in the pits, out of

the spectator area, or in preparation for a race.

d. The carburetor must be the stock, unmodified carburetor model that was furnished with the

engine. No parts such as the choke shall be removed from the carburetor. All engines must

be normally aspirated and have a piston ported or reed valve fuel induction system.

Classic Thunderboat Hydro - Specialty Class (2009 June rooster tail p.45)

ENGINE SPECIFICATIONS

IMPBA Super Sport Engine specification rules, as outlined in the IMPBA rulebook

Section I - Large Scale Gasoline will apply with the following exceptions.

1. Any exhaust system allowed. The exhaust system must be concealed within the hull and may

exit from rear, side or bottom. Only the outlet may show. All boats must meet current IMPBA

noise rules.

2. An unmodified Walbro #257 carburetor may be substituted for the factory original carburetor.

3. Any composite or copper type replacement gasket set may be used but must be minimum

.014” to maximum .018” thickness.

The engine must be equipped with a recoil starter and this starter must be the primary means of

starting the engine. Supplementary starters are allowed. The brand of starter is optional.

Based on the above rules and the fact My RCMK EVO 254 motor came in a sealed factory box from the US distributor; Why is it not a legal stock Thunderboat engine? This is what the Technical committee and the IMPBA Executive Council have to consider. Not that the motor turns more RPM, more HP and is perhaps less expensive than the previous Super Sport Engines.

It seems so simple WHAT IS THE PROBLEM?

I suggest you e-mail or phone your District Director, the IMPBA President, the Gas Director and the Technical Committee Director and point out the above reasoning and ask them why any motor that meets the engine spec is not a stock motor and legal Thunderboat motor. KISS

I see suggestions that we just change the Super Sport Engine Specs. Technically the Super Sport Engine Specs are now tied to the Thunderboat rules and cannot be changed for two years.
 
"I see suggestions that we just change the Super Sport Engine Specs. Technically the Super Sport Engine Specs are now tied to the Thunderboat rules and cannot be changed for two years."

FYI- this is opinion, not fact and is incorrect since the SS engine rules affect different classes.
 
I'm not waiting Bill, I'm jumping in :D . I think Brian's "Lauterbach" desisn is unbelievable. My intitial questions on engines have been cleared up and I'm going with a Zenoah. I'm really not looking for a "fast class" and as long as everyone's on the same playing field, I'm good to go! Hopeffully I can have this thing running next year. Thanks for everyones help and input.

J. Pflueger
Go for it now, waiting for the impba to figure out the rule is not needed.

If every one runs the Zenoah or first Rcmk motor the boats all should be even. Sure there will be someone with a edge on speed at every race, as long as they are not modding their motor good for them.

To me and I am just a rookie at this gas racing, the SS motor rule is meant to have someone buy a motor in a box and be able to compete with anyone at the race with out getting a lot of costly mods done.

NOw if some company makes a better motor at a fair price in a box and doesnt have to be modded to race it will become the motor of choice. The cost of a (stock) motor should not be a problem to anyone that really races and wants to win.

This motor updating thing is a natural process.

All nitro motors back in the day had to be timmed up and modded to run in a race and win, now you can buy one in the box ready to race. Sure there are some fine tunning mods done still but not like in the past.

I have not cut on a nitro motor for many years now.

What mod makes the big gain in rpm? exhaust timming? head clearance? Maybe SS rule should determine the timming numbers for stock motors and a way to measure on tear down. Seems to me they make rules that are not easy to understand and enforce.

What about the RCMK evo kit for the Zenoah $129 not too bad of a upgrade cost. If the EVO is approved how about allowing a upgraded Zenoah. Then zenoah brings out their own better motor and everyone is back to equal power in a lower cost motor for the SS class.

AS if Zenoah and Rcmk care how many SS rule boaters are out there, Im not so sure we have any affect on their marketing plans...

I wlll be racing the cheapest and fastest motor out there in my T boat so I can run with the leaders.
 
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"I see suggestions that we just change the Super Sport Engine Specs. Technically the Super Sport Engine Specs are now tied to the Thunderboat rules and cannot be changed for two years."

FYI- this is opinion, not fact and is incorrect since the SS engine rules affect different classes.

OK, then this is fact, not opinion SS engines apply with exceptions listed below, and the meaning originally was stated as some want to change SS engine rules, but the current SS rules DO apply and with reference to thunderboat cannot be changed.

FACT:

ENGINE SPECIFICATIONS

IMPBA Super Sport Engine specification rules, as outlined in the IMPBA rulebook

Section I - Large Scale Gasoline will apply with the following exceptions.

1. Any exhaust system allowed. The exhaust system must be concealed within the hull and may

exit from rear, side or bottom. Only the outlet may show. All boats must meet current IMPBA

noise rules.

2. An unmodified Walbro #257 carburetor may be substituted for the factory original carburetor.

3. Any composite or copper type replacement gasket set may be used but must be minimum

.014” to maximum .018” thickness.

The engine must be equipped with a recoil starter and this starter must be the primary means of

starting the engine. Supplementary starters are allowed. The brand of starter is option
 
I really feel that the Technical Committee Director should get this cleared up in black and white. I've also read in a proposal 26cc and another 27cc limits. I guess I'm still up in the air after all and don't know what I can purchase as far as a engine. :blink:

J. Pflueger
 
I'm going to be honest and tell ya what I'm reading. My problem; is this the bottom line? I read that originaly there was a restriction on specified engine mfg. for this class. In the last two revisions before the final vote these specific engine mfg. restritions were omitted as to the specific Thunder Boat class. Looks like the final vote was made by memebership without naming any motor as legal or not legal. It looks to me as though there are two sets of rules. First, whats in black and white and voted on. Second, A set of purposed rules that never made it to the final vote. That's the way I read all this now right or wrong and why I'm still very confused as to why no one here can say with any certainty whats legal and whats not. I don't want to "just take my chances" I want to be "legal". And most of all I want to have fun with this class!! Until the tech director clears this up I'm on the sideline with a boat and no motor I guess. I've got some time as I haven't ordered my boat yet but things will start moving in that direction soon.

J. Pflueger
 
I know this is all crazy, but as the IMPBA president said to me yesterday I spoke with him at the spencer park D-2 race sunday, The RCMK EVO is NOT legal for a SS class engine, so as of now thats what stands.
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