Is the OB class doomed?

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Okay, here is one of my new FE Outboard Lower Unit Concept drawing that I am going to send out for quote and have made for my current O/B Hydro project. Yea I know it's an FE but all the things the nitro car motors will need is there. Notice how extremely low the mounting plate is. This drops the c/g of the unit considerably lower that any other unit available for nitro. Also notice the engine is laying at 40 degrees.

This is a 7.5 size cable I'm showing you so that yall can get ideas for a 3.5cc size unit. The radius cable radius is the same radius of the K&B 7.5. This unit is a highly modified configuration of Wedall's Gas lower unit.

The skeg is offset and is part of the cav-plate. The radius edge construction makes it very strong and the skeg has a rigger support that reduces flex (this rigger will ride clear of the waters surface and cause no water drag at plane) The cable is squared on both ends just as a typical outboard. The prop assembly housing is a replaceable strut type construction and easy to machine and replace if needed.

Like Wendall's unit, my FE version is going to be machined from black delrin to be as light as possible. If someone will take some interest in this idea for nitro and build a purpose designed lower unit for car engines you could end the strangle hold that outboard manufacturers have had on these classes for that past 40 years.

If yall will pool all your talents and machine capabilities together and maybe build something like this as a collective manufacturing group this could be a solution for the 3.5 class. Racing outboards is going to be a hard sell for yall if you don't have something that can be bought off the shelf as a complete unit or a partial kit of some kind. Anyway, there is an idea for you to think about. - Carl
 

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Hi Carl,

I actually disagree with the high CoG you speak of being an issue...I get the best lap times I have ever seen (on a 21 nitro setup) with my R2104 on a gearbox...handles awesome. Depending on gearing you have a lot of options for props. I am using an OS lower, but a Lawless would also work well.

This setup is also using a car pipe, not a 'real' outboard tuned pipe.

while I was 'only' getting 85ish (mid 50mph) kmh on the straights, the corner speed was awesome. This setup is faster (lap times) than my Mod Keep motors and Cooper pipe setups which do which go 60mph+ top end.

 
Hi Carl,

I actually disagree with the high CoG you speak of being an issue...I get the best lap times I have ever seen (on a 21 nitro setup) with my R2104 on a gearbox...handles awesome. Depending on gearing you have a lot of options for props. I am using an OS lower, but a Lawless would also work well.

This setup is also using a car pipe, not a 'real' outboard tuned pipe.

while I was 'only' getting 85ish (mid 50mph) kmh on the straights, the corner speed was awesome. This setup is faster (lap times) than my Mod Keep motors and Cooper pipe setups which do which go 60mph+ top end.


This is just freakin’ awesome 👌 I have never had any CoG issue with gearbox setup. The boat are fast and reliable. You can pick an engine of your choice, find the optimal gear ratio based on prop and course, then you’re good to go.
Good job on that boat, Kris 👌
 
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I 3D printed an outboard lower unit for electric motors. It wouldn't work for nitro without a bigger metal core. By the way, we ran a Mike Bontoft custom quick change gear box in our full sized hydro. A smaller version might be great for nitro engines. I could get a metal 3D printed version built into the lower unit made fairly inexpensively. These days metal 3D printing is quite inexpensive.

Lohring Miller

Motor with Gearbox.JPG
 
Hi:
Okay, here is one of my new FE Outboard Lower Unit Concept drawing that I am going to send out for quote and have made for my current O/B Hydro project. Yea I know it's an FE but all the things the nitro car motors will need is there. Notice how extremely low the mounting plate is. This drops the c/g of the unit considerably lower that any other unit available for nitro. Also notice the engine is laying at 40 degrees.

This is a 7.5 size cable I'm showing you so that yall can get ideas for a 3.5cc size unit. The radius cable radius is the same radius of the K&B 7.5. This unit is a highly modified configuration of Wedall's Gas lower unit.

The skeg is offset and is part of the cav-plate. The radius edge construction makes it very strong and the skeg has a rigger support that reduces flex (this rigger will ride clear of the waters surface and cause no water drag at plane) The cable is squared on both ends just as a typical outboard. The prop assembly housing is a replaceable strut type construction and easy to machine and replace if needed.

Like Wendall's unit, my FE version is going to be machined from black delrin to be as light as possible. If someone will take some interest in this idea for nitro and build a purpose designed lower unit for car engines you could end the strangle hold that outboard manufacturers have had on these classes for that past 40 years.

If yall will pool all your talents and machine capabilities together and maybe build something like this as a collective manufacturing group this could be a solution for the 3.5 class. Racing outboards is going to be a hard sell for yall if you don't have something that can be bought off the shelf as a complete unit or a partial kit of some kind. Anyway, there is an idea for you to think about. - Carl
Excellent design work!... perhaps, this type of Outboard Lower Unit allows the placement of a nitro engine with gearbox, without condemning the C.G. so much.
I really love this design, Carl Van Houten... it is a very well achieved practicality and clean design!!... thanks for sharing it; thank you very much!
 
Very good design Carl I wished somebody would pick this design up and start manufacturing this. I don't know how much the price would be for one of these would it be possible to keep it under $100 I was hoping that somebody would be able to 3D print lower units but as I read they say that it's expensive to do so now. I guess 3D printing is only good for some things but not the best things. Maybe one day they'll allow inboard electric motors on an outboard tunnel or strut unit and still call them outboards in support of the hobby and keeping prices lower. I do think that it is cheaper to go with inboard motor strut and rudder then to buy a lower unit for over $100. All I can say is start thinking about the price of the hobby and making things for a cheaper price but yet still make enough money that you will make for your time
 
Hi ACTION JACKSON:
... Maybe one day they'll allow inboard electric motors on an outboard tunnel or strut unit and still call them outboards in support of the hobby and keeping prices lower....
I´m very sorry to disagree with you... I don't think that, to save a category, you have to change its configuration. For that, there are already OTHER categories of RC speedboats.
I prefer the usual OBs, and if they are 3.5cc Glow Tunnels Boats, MUCH BETTER!!... Although I feel a certain envy of the 1/4 scale ones: they are jewels on the water!!
 
That looks really good Carl. By chance is there a rough guesstimate on the price that might be
I only posted that concept drawing hoping to encourage some new thought. People think that you can just keep running the same left handed nitro engines but the truth is that is exactly why you are where you are now.

O/B racers are likely going to have to make this happen or it just won't get done. Who ever steps up to the plate will have to be serious. Maybe one of the current lower unit manufacturers will pick this ball up and run with it,

TFL
LAWLESS
HYPER PERFORMANCE
OTHERS???
 
GREAT! Get them tested and on the market! Advice: They place the engine too high... You need to get the power head down LOW!

While I agree using adaptors on Lawless and OS lower units is not the best for CoG...the motors sit lower on these new units (that I pictured above) than current setups allow...so IMO, you are worrying too much about CoG (as far as height goes)

I have been running modified lawless lower units for years with motors at this height and have seen no need to get it lower.

on your unit above, how much further back is the prop from the transom compared to an OD?

Ultimately, the hobby is dead compared to what it used to be. the 'hay day' is done and dusted...this really hurts me to say, but it is the reality. Check out the average age of racer at ANY event recently, particularly nitro or Gas. FEW has some younger competitors, but the average age is still very high.

Thanks
Kris
 
This could be the next best thing??
I agree with the very low participation. It's just a fact and if it were that way across the board I would say "its dusted" as well BUT, the decline is the result of multifaceted issues. Other classes are on the rise. Just recently a new gas class was added: Super Boat. So why is the current class attraction moving away from outboards?

For the ones who are still interested in racing O/B's the core upfront issues are still first availability and second price then third comes glow plug prices. Gone for ever are the days of the $3.00 glow plugs. They are $8.00 to $12.00 now days and then there is fuel prices. Feeding a 7.5cc fuel all afternoon can get a bit pricy.

At the moment the neat & simple left handed power head that we have enjoyed for many years can not be purchased new anymore and we are now left with lower units that require them.

If a comeback is possible from this point, a lower unit needs to be built around a right hand engine to prevent this from ever happening again down the road. Will it be gear drive, belt drive or right hand direct drive? Somebody that is interested in outboards, retired and owns a decent CNC can fix the current availability issue fairly quickly but who is that person?
 
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