IMPBA legal outboards

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I really don't understand why this is being discussed but I can tell you the reason the rules were written like they are. In 1979 (I think correct year), Myself, Doc turner and Ed lackey were on our way to the Internats in Orlando Fl. and while on the road we wrote a rough proposal to try to get O.B.'s into IMPBA. It was presented to the board and they said a flat NO and said they didn't need any more classes. After the race (and after I won D-hydro heat racing with an O.B.) we came home and Doc turner got on the telephone and talked to all the directors and convinced them to give the O.B. classes a chance. Fred McBroom was the president and he thought hydros were the only classes that were important and he was against it all the way but the board won out. A few simple rules were put in place to allow O.B. tunnel hulls and hydros to be run. Some one came up with the idea that Hydros would run better with a turn fin instead of turning the motor ( I don't remember the reason that was given) but that's how that rule came into play. Originally there were no specifics given for the motors or boats and It was probably done that way just to get the issue closed. I truly believe they though the classes wouldn't last but it seems the O.B's are still doing well after all these years.
Wow. Those are great history points Tommy. I had no idea Doc helped get the OB classes established. If the definition of the outboard is approved by the membership and written into the rule books, that should at least keep the class as it was originally intended by you and others.
 
My intent is to define an outboard something like this. "An outboard motor (nitro, fast electric or gas)"shall be defined by the following criteria

1, it shall be a self contained power unit, and must be removable as a complete unit.

2, it shall mount externally to a nearly vertical transom.

3, it shall use a metal propeller that drives the boat by direct contact with the water, no air propulsion.

4, it shall be steerable as a unit for outboard tunnels, but may be locked in place, for outboard hydros, if the hydro is steered by a separate water rudder.

5. The intent of these rules is to make the outboard resemble the full size outboards used in racing.

6, nitro engine classes shall consist of A, B, C, D, E and F (modified) B sport (stock apearing) SST 45 (modified but no tuned pipe.

7, fast electric (to be determined)

8, gas (to be determined )

9, grandfathered outboards, outboards currently being raced in IMPBA that do not fit the new rules, will be grandfathered as needed. Not all will be allowed.

This is just a rough draft. Please feel free to comment. If you don't currently run one of the "questionable outboard", don't ask to get one grandfathered.

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Bob,This looks great as a first pass except #4. Outboard Hydros should be treated just like outboard tunnels. The engine can not be locked down and a separate rudder should not be allowed on ob tunnels or ob hydros.
 
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In all fairness, full size outboard hydros typically run a separate mounted rudder, if we're trying to keep it "Correct".

Just because we haven't seen full size manufactures design outside of the box lower unit designs, does not mean they aren't an innovation worth taking further. Let's be honest, K&B lowers won't last forever, eventually that stock will be depleted. Lawless is a great option, as well as O.S. But what's left? Hyperprod sells lowers that have never been well reviewed or that I've ever seen in competitive racing.

If someone can innovate new ideas into tunnels isn't that a good thing? We should be promoting these ideas, giving people more options. The advantage other class's hold over outboards is the options you have. More boats, more motors, more parts. Why limit how far tunnels can expand when that's something we all agree we want. When you eliminate choices and limit innovation, growth stops.

Not to mention, Shane's "inboards" turn as a whole unit under one power. If a traditional transom is such a taboo subject, a simple L bracket would keep him within those graces, such as the yellow hull in the fourth picture.
 
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i would like to see them also

marty

power head an lower same manufacture the same
I dont see anything that would make the Lawless have a need to be grandfathered. Where did that come from????? They are a standard lower unit that mounts to a vertical transom.
Ron, read the quote I quoted. They are discussing making only Power-head/lower combos from same manufacturer being legal.

I can't imagine why that would be a good idea, or necessary. Taking this thing to an extreme, for no good reason at all.
 
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Rather than make simplistic rules complicated, our focus should be on why our race, the World OB Tunnel Championships, has had its number of boat entries slashed in half and then some within 4 years of a race that brought in over 200 boats.
 
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i would like to see them also

marty

power head an lower same manufacture the same
I dont see anything that would make the Lawless have a need to be grandfathered. Where did that come from????? They are a standard lower unit that mounts to a vertical transom.
Ron, read the quote I quoted. They are discussing making only Power-head/lower combos from same manufacturer being legal.
I can't imagine why that would be a good idea, or necessary. Taking this thing to an extreme, for no good reason at all.
Oh, I see what you mean. That's out for sure for reasons Brandon mentioned above. We still have lowers from Lawless, OS, and Hyperprod. Maybe there will be others but not smart to exclude the few production lowers we still have left.
 
Darin, reread the comment(s). Marty was thinking that it's supposed to be the same mfgr for powerhead and lower. That is for SPORT(IMPBA) or STOCK (NAMBA) class only. This discussion is what makes an outboard an outboard. K&B and Lawless lowers are availabe and have always been. To me, there has always been reliable lowers out there for the 7.5 + classes to be purchased.
 
47 comments and 1000 views!! This must be important enough to need the attention of all outboard racers

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If it was important there would be a 1000 post not 47 .

Just saying ,800 views is me seeing what you two are going to say next ,which affects me and my wallet.
 
Well, the consenses is that there is nothing wrong with the current. Outboard rules in IMPBA or NAMBA. I guess the people have spoken. I can quit wasting my time. You can do what you want.

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Hi,

example what is not a outborder ,the pic show motor mount on transom ,is adjustable and has controlable propeller pitch . But the fin is stearable and it is only a thing to tought . The running sushi ,as the blade are made from two cool kitchen knife .

Happy Amps Christian

image.jpeg

image.jpeg
 
As a new tunnel boater my concerns are where did all the gas tunnels go .there is not any signed up for the fall nats ? I myself have several boats a d a e and a gas that would fall into open tunnel in my district. I let other people drive my boats just trying to keep the tunnel classes alive .Instead of trying to take more boats out of the running the effort should be to make the classes grow
 
Hi,

example what is not a outborder ,the pic show motor mount on transom ,is adjustable and has controlable propeller pitch . But the fin is stearable and it is only a thing to tought . The running sushi ,as the blade are made from two cool kitchen knife .

Happy Amps Christian
OK, I have to ask. Did that concept actually work? It looks like someone took the blade off of Rod Geraghty's margarita blender and stuck it on an outdrive.

JD
 
Hi Jerry ,

since some years i want to build up such drive and now i had the time to do it . Belong a lot to the flywheelpropeller i show in the propeller form here IW . So 5 days ago i took a modelhelicopter rear countertorque gear and adopt it to the short toothbelt drive with the high torque outrunner . The two propellerblad are cut from two kitchen knife with wedge shape profile. Drill the hole that it can mount by the srew and ready for a first test in my pool . And it lookes very promising . With no angle of attace start to rev up the drive and than ad pitch will result in a realy good working surface drive that has very high trust . Moore than i knew from normal outborder with surface propellers . This led me to buy a fifeblade helicopter main rotor head ,as i want to test it for my flywheelpropeller system .

I will make a small video on youtube next days with my son and show it at flywheelpropeller tread here.

Happy Amps Christian

image.jpeg

image.jpeg
 
Hi Jerry ,

since some years i want to build up such drive and now i had the time to do it . Belong a lot to the flywheelpropeller i show in the propeller form here IW . So 5 days ago i took a modelhelicopter rear countertorque gear and adopt it to the short toothbelt drive with the high torque outrunner . The two propellerblad are cut from two kitchen knife with wedge shape profile. Drill the hole that it can mount by the srew and ready for a first test in my pool . And it lookes very promising . With no angle of attace start to rev up the drive and than ad pitch will result in a realy good working surface drive that has very high trust . Moore than i knew from normal outborder with surface propellers . This led me to buy a fifeblade helicopter main rotor head ,as i want to test it for my flywheelpropeller system .

I will make a small video on youtube next days with my son and show it at flywheelpropeller tread here.

Happy Amps Christian
Well, that is a terrific example of "thinking outside the box." About the only "thinking outside the box" I do is pondering my order at the drive through at the Jack In The Box.

JD
 
Hi,

a very short vid of the prop . The problem is the toothbelt that broke and so i can not shot full power operation . The video show only slow operaation . I change the pitch ,but this is moore the barge operation speed . https://youtu.be/hSKaDLaL4aQ .

For the next i will try a direkt motor drive without any gear .
 
Wow seeing this is alittle crazy. I understand that people want a tunnel with the engine mounted vertical on the back of the boat. We have a lack of outboard lower manufactured in the hobbie. Ernie made a adapter to use different engines mounted vertical for a 67/80 and 45 RS type engines mounted on a K&B 7.5 lower. Can't use a 90 or 1.00 or 1.01 cube engines because the lowers can't support the power being put on the shaft.

Here's what I have. Now if anyone want to collectively come in with me I have the design for a 1cube plus engines adapter the problem is whose going to build lowers to support the power ??? The lowers are the problem that's why people are thinking outside the box to keep the classes alive.

Julian
 
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