Towers anyone ?

[will350]

I'm sort of "in the twilight" of my life. My brain works OK but the rest of me has started to go down hill so I have alot of time to think about this stuff.
There's an outfit in Cal. that builds these tiny little 4 cylinder motors out of weed eater parts. You can get it in 25cc,30cc or 35cc cylinders times 2,3 or 4.
The things make roughly 30hp @ 140cc and turn some astromonical rpm.
There isn't enough room under the flywheel for more ignition or they'ld have more cylinders. Coupling them wouldn't be hard.........but think about "tuning" them and ALL those tiny little expansion chambers.... ("Porquipine-esque" ?)
11 100cc units= a screaming 1100cc motor............. 44 carbs,44 plugs and 44 chambers!
What am I thinking?It'd be a thoroughly terminal headache to get it TO run and probably worse to KEEP it running. It would be interesting though.
See.......... I have waaaaaaayyyyyy to much time to "think".
Will

Interesting brainstorming Will and everyone. The clutch subject reminds me of something that I considered when 80 hp was tops and that was building a frame attached to the top of and Merc 800 mid section with a driveshaft extended up thru the center with a bearing at the top. This contraptaion would be tall enough to mount four or so 30 hp chainsaw or gocart engines in a staggerd radial fasion using a chain and sprocket connecting each engine to the driveshaft. I could never decide if it would need just one or two motors running a gocart clutch and the rest straight drive or all needing clutches. I wounder if noa would have alowed this in Unlimited II? It would almost have been worth the effort just to see the reaction when it was unloaded.
I think I can hear the laughing out there from here.

Tom

[John (Taylor) Gabrowski]

I was staring at a pile of those air conditioning electric (12 volt) engaging compressor clutches and I figured I would pop the question??? Have you ever seen the innards and workings of the various versions of those and in that, would they be of any use cut all up to useable size to horsepower applications and engines like these???

[will350]

I was going to go the the SOA "oldtimers" meeting last night but had a very early AM call I had to be here for so...............
Got this from my brother this AM. This is something that Dwight Malhiot did about 25 years ago. Since I wasn't there to actually "see" it,I'm not positive,but I think it's a Kawasaki 500cc triple with W/C heads and a belt driven Mercury ignition.
I was ,at one time, a service manager for a Kawasaki dealership and in their day,Kawasaki triples(250,350,500,750 2 strokes) were pretty near "untouchable" on the street in stock form and could be really scarey when modified.
I contacted SSwhite in regards to their flex shafts yesterday. Am hoping to hear something from them. We will see.
Will

[7500Blizzard]

Will if you tried the clutch setup and got to stay dry and tuned properly it shouldn't eat belts that bad, a champ sled spins about 10500rpms clutch engages about 7800rpms with a couple hundred 1" or larger pics in the track and i can guarantee there's not a prop in the world that will bite harder that that.

[will350]

Ken, It's not a matter of belt slippage. The drive clutch is regulated by RPM and the driven clutch is reactionary ( pretty sure that you know that but I'm putting that in for folks who don't) Propellers don't present the same constant load to the clutch as a track on a snowmobile. When the prop bites,the RPMs come down and the drive clutch "shifts" and the driven clutch reacts and shifts. The motor spins up because of the shift but the prop slows down and you lose the bite then it "shifts" again.
Then,because of the shift, the prop ventilates and starts the whole process over again. One of those "vicious circle" deals. If you do manage to get it going every time the prop comes out and the motor spins up some, the clutch "wants" to shift and,because of the "time" factor,it can't keep up with what's happening at the prop end. I'm pretty sure that's why folks who have tried this gave up(and I have "heard" that it's been tried before and about all that happened was lots of sceaming belt sounds)
I feel if you can control the driven clutch(becuase you're "smarter" than it)
this will work and you can run just about any prop because you can "change gears". I have couple of driven clutches that I look at and "ponder" over every so often trying "see" how I can do this. I think it can be done and the results will be well worth the effort,it's just going to take a little time and thought.
There will be some extra weight and and a really different "looking" unit and a lot of "what the heck is that thing?" but I'm used to that.
Will

Will if you tried the clutch setup and got to stay dry and tuned properly it shouldn't eat belts that bad, a champ sled spins about 10500rpms clutch engages about 7800rpms with a couple hundred 1" or larger pics in the track and i can guarantee there's not a prop in the world that will bite harder that that.

[will350]

After a couple phone calls and failed email attempts, I finally got through to SS White Technologies (the flex shaft folks). Unlike Hilliard corp. ( the clutch people who totally blew me off), they're happy to talk to me and consider my idea about a flex cable drive. I sent a couple Jpegs to them yesterday(1 of the rotax and the rather crude sketch that I posted here) and a rough explaination of what I'm up to. This AM I got a reply, the jist of which is , they're going to assign this to someone for evaluation and get back to me in a few days. You have no idea how refreshing it is to be treated this way as a "one man show" vs a "mega corp.". This could be a very interesting turn of events...
Will

[Dan M]

Will,

Good luck with the flex shafts. I've been thinking about the "clutch" situation that you have discussed in previous posts. Snowmobile clutches typically respond the way that you mentioned. The primary engages and the secondary allows the "upshift". I can see why this is a problem with the prop loading and unloading, causing the secondary to shift back and forth. It got me thinking about how other variable drives handle the speed or gear ratio changes. Because the snomobile type secondary is actuated by spring pressure and helix angle, you're trying to balance the load on the track with the power output of the motor. On a sled this works very well because the load from the track is almost constant. The grip of the track pretty much stays the same thru the shifting range. In the boat scenario, the prop doesn't give the consistant load to the clutch, and it is constantly searching for the best ratio. Could the secondary be set up in such a way that it is only allowed to shift via a cam type action? Think throw out bearing and fork setup to allow the sheaves to move. No springs or very light duty. Mechanically set the distances that the sheaves can move. That way, the primary acts as the "squeeze " to the belt, and the ratio will only shift if it is allowed to by letting the secondary open up via mechanical means. It's not like we need another pedal in the boat or anything, but you could set up a low/high arrangement with a pedal in the boat. Start the motor, the primary is disengaged. Set the secondary to "low gear" by pushing the pedal, and bring up the R's to engage the primary. Boat jumps up on plane in low gear and accelerates to max motor rpm. Gently release the pedal, and the primary will shift out to where ever the secondary allows the ratio to go.

It's Friday and it's been a long week. My mind may have missed something, but Ron sounds like he really wants the clutch thing to work. My $.02

Good luck with all the projects.

Dan

[RichardKCMo]

I was wondering if anyone remembers that Buick had what was called a dynaflush/flow trans., just think those wonderful cars will be made by foriegners now.
I 'm not mechanical, just a thought.
Richard F.

[7500Blizzard]

I still think you could get a clutch system to work if set up right check out a sno-x sled there air as much or more than they're on the ground and they don't have too much troouble with all the shifting. Or set it up with a 1 1/2- 2'' pulley on the shaft and a long travel tensioner to make up the size diff from the secondary.

[will350]

Dan,
An altogether excellent thought. I've been sort of "stuck"on the thought of controlling the drive clutch while allowing the driven clutch to "do it's thing".
This new perspective,in the form of feedback, is more "doable" than what I had in mind. Looking at the problem from this angle,The simple and easy thing to do is not even worry about the shifting business but modify the clutches so that ,say, the drive clutch comes in at 4000 and the driven clutch can only open to a "given" point which would be adjustable to change the ratio. The rational here is that,with a low enough engagement speed on the driven side,
when the wheel bites, it won't shift as radically as it would with normal driven clutch. Added to that the more RPM,the more belt tension. Another plus is having the belt to absorb the impulse loads to the foot. Experience has shown me that you can run alot more load when the load is "damped" or added gradually(so to speak)
When it comes to being the "sharpest tack in the box" I'm fairly
"pointy", but there's always someone with a view that I didn't or couldn't "see" that puts a new light on the subject. I always appreciate FEEDBACK!
Whether it's negative or positive... I always appreciate it.
Thanks Dan,your input has set off a whole new approach to solving the issue of making this work.
Will



[QUOTE=Dan M]Will,
Could the secondary be set up in such a way that it is only allowed to shift via a cam type action? Think throw out bearing and fork setup to allow the sheaves to move. No springs or very light duty. Mechanically set the distances that the sheaves can move. That way, the primary acts as the "squeeze " to the belt, and the ratio will only shift if it is allowed to by letting the secondary open up via mechanical means.