Towers anyone ?

[7500Blizzard]

If you want Rotax stuff there's still lots around all of the 340 440 and 521 bottom halves are the same and cylinders are out there along with heads. You might have a hard time finding many xenoah 250l/c's restoring rupp's is getting popular (allouette's too)..

[7500Blizzard]

The cases listed above run from 78-85 maybe even a few of the newr with same case.

[will350]

I put out some feelers on another site and found a couple 250s and 3 340s.The 250s need pistons and rings(probably some crank work too) and 1 of the 340s is an "NOS" never run "in the crate" but I'm pretty strapped for "extra money" right now so......(and I some how have lost that address)
I have 2 354s and a 454 Rotax but they all have that maddening Bosche
ignition with 2 of everything. I do have an ND ignition for Rotax but it's not a "bolt on" for the motors I have. The crank taper is too small and I'd have to do some machine work on the cases to get the stator to center right. I either have to get a whole later crank or a late ignition end of the crank and install it on mine. That might be the easiest and least expensive solution.
When it ran "right" , the Rotax was a rocket,"better" everywhere on the course than the Polaris but not as consistant.The Polaris(once I "figured" it out) was very reliable and consistant and tougher than John Wayne no matter how much you abused it.These are NOT the delicate and finicky things that most PRO motors are because of their "intended" use. No offense but I really wouldn't one of the current PRO motors in a rig that you're going to running off 50-60 miles into the wilderness. That doesn't mean Rotax and Polaris motors don't fail or break..... they're just not as likely to because their design parameters and their intended use. They're very,very robust motors.
Will

If you want Rotax stuff there's still lots around all of the 340 440 and 521 bottom halves are the same and cylinders are out there along with heads. You might have a hard time finding many xenoah 250l/c's restoring rupp's is getting popular (allouette's too)..

[QUINAULTRACING]

WILL, Been thinking about driveshafts. Do you know if anyone has ever tried to use wire rope. Like the piece between 50 merc carbs or a speedometer cable but bigger. Ends could be put on very easily and if you used rope with the correct wrap, as you were putting power to the shaft it would try to unwind but as it tried to unwind it would try to get longer. With the shaft between the crank and drive shaft to the lower unit. It would limit how much it could unwind. Even better might be to run the wire rope say 7/8" inside 1" or 15/16" pipe to keep it from unwinding too much. It would not have to be attached to the ends to do the job. LATER..steve

[Ron Hill]

I asked Will the same question last year....As Chad and I thought we could build and OUTBOARD like the K and B Model outboard...We actually were thinking of using the wring that holds up telephone poles... I'm trying to stay focused on only 40 projects, but I think it will work....and I was going to use a JET outboard drive....

[will350]

This is another one of those things that runs through my brain at times.
If you look at weed eater cables,you'll see that they "wind up" when they"drive" the spool. They use tension to transmit load.They're specifically wound to transmit loads like that. They get shorter with more load,hence the slip couplers on the ends(keeps the end load off the motor). If you tried to turn them "backwards"( so to speak) instead of "pulling",you'd be "pushing" on the wires in the cable.Not saying that you"couldn't" do that but the inherent strength(and design strength) in cable(pretty near any cable) is all about tension and not "compression".
I think you could "do" this with wire rope,a "torque tube" and , let's say,"bushings". The trick is how you're going to handle the thrust and side load on the prop shaft. You're going to want the prop shaft to "stay still".No fore and aft movement. Means your "power head" end will have to float or you could "float" both ends(might be better). The amount of "bend" that you can pull off with this "idea".........? Probably one of those "trial and error" things.
The deciding factors are going to be how much deflection and what sort of friction loss you're going to encounter vs your cable size? There are some real benefits in a drive like this.None of those bloody expensive L/U gears to go TU for one and a smoother transmission of power cause the cable will have a tendency to "absorb" the impulses from the motor. You should be able to figure out couplers for both ends and they should hold up fairly well too cause of that "absorbtion factor". It will require a bit of R&D but it'll be inexpensive(once it's worked out) and it might even pass the PRO "drive" rules......(providing you don't "kill" the rest of the field first time out.That's sure to get it banned for eternity)
It's an ,all in all,doable thing and simple really(I use the "KISS" principle on everything),it's pretty much just a matter of "doing it"
Will

WILL, Been thinking about driveshafts. Do you know if anyone has ever tried to use wire rope. Like the piece between 50 merc carbs or a speedometer cable but bigger. Ends could be put on very easily and if you used rope with the correct wrap, as you were putting power to the shaft it would try to unwind but as it tried to unwind it would try to get longer. With the shaft between the crank and drive shaft to the lower unit. It would limit how much it could unwind. Even better might be to run the wire rope say 7/8" inside 1" or 15/16" pipe to keep it from unwinding too much. It would not have to be attached to the ends to do the job. LATER..steve

[will350]

I ,obviously, have too much time on my hands..................
This is the way I "sort of" envision a really simple cable drive. Basically a smooth bore housing( appropiate wall thickness pipe),bent to the correct radius,skeg on the bottom. Propshaft afixed to the cable through 2 bearings to handle thrust and side load.The inner bushings are to keep the cable from "winding up" and spread out the friction points. After I got this drawing done,
I started thinking about "how" you were going to load them in the housing....
I think making them a ring would make it tougher (you have to figure they're going to have to slide over one end or the other and having cable to prop shaft-power head couplers ,that might be difficult) So...... after some thought, I think you could make them spherical and "split" them. That way you can load them on the cable as you slide it in the housing and they present more surface to the cable and less surface to the housing. That should have less friction than 3-4 times as many "rings". You might get away with a phenolic water lubricated bearing for the prop shaft and a water lubed phenolic thrust bearing. Really CHEAP and easy to R&R pieces in and out of.
Friction loss will depend on the size of the cable vs the amount of bend.
The smaller the cable you can get away with,the smaller the housing can be.
If 1/2" cable will handle the loads,you could probably get the overall width down to an inch or so. BIG BENEFIT compared to 2 1/2+ inches that you're usually dragging around.
So what do you think?
Will

[John Smallin]

Will
Maybe looking at model engine exploded view will help. They have a teflon sleeve around the cable with square ends just like a speedometer cable. The thrust bushing at the lower end is fixed in place as are the bearings at the engine end. The housing is split lengthwise about the shaft. Go to www.mecoa.com/kb and click exploded view, cursor down to model 8907 or 8935 and click exploded view.
I couldn't figure out how to attach the file.
Regards
John

[Ron Hill]

Does anyone but me remember what Tommy Lasoda answered when he was questioned about Dave Kingman's performance...there were 57 bleeps in a minute and fourty second tape...Tommy started out What the F&^*ing do you hink of his performance...

What do I think??? Will: I won't get BLEEPED out but but you are going to need more time when we start building these things by the thousands. I think your PERFORMANCE here has been amazing, your tower is awesome...and thing drive, with clutch, will be a screamer...

A. I will make any casting you need.
B. How much will this project cost? I will buy into it TODAY...
C There are air cooled HONDA FOUR STROKE VERTICAL SHAFT MOTORS of about 25-35 HP...Electric start... What do you think about a Honda for power????
D. I'll start building my FOAM BOAT NEXT week...

[will350]

This what I ment when I said "spherical bushing". Easy to see that they suppor5t the cable really well and cut way down on the housing contact.
I don't think that a "K&B" sort of thing is feasable. I looked high and low for a "spiral wrapped" drive cable and no can find, I feel like a minimum DIA. would be 1/2"+ and we're going to be transmitting a LOT of power. I'm not sure if a "normal" steel cable will do but that's available in a variety of sizes and grades.
Will