motorcycle engine for canoe mv?

Shoeshine · Post by **Shoeshine** » Thu Sep 30, 2010 12:10 am

OK my first stupid question for the 2011 season...

I am thinking on possibilities for a small MV based on a trashed outrigger canoe hull I can obtain for free/favors.

My first thought is to put a motorcycle rear end through the hull at the back.

I am trying to figure out how to figure out what kind of engine size I neeed to be thinking about/looking for.

The hull would seat maybe 6 people in actual canoe state. You could probably pile on a dozen if you didnt have to worry about capsizing.

Setting aside suspension/frame questions. (That is another discussion going on concurrently off-site) what kind of power do you think I would need in first gear to push 8-10 people (max... 4-6 would work for the idea) + around 300-400lbs vehicle weight + weight of the engine itself @ 5mph. Would a 250cc cut it? are we talking a 1200? more?

And please tell me if I am completely off my rocker. I have a 600cc honda as a personal bike with which I have sucessfully pulled a parade contraption (utility trailer frame with 2 drummers and a tympani). Didn't seem to stress the engine, but of course this was on a street. But I cant really say that I understand gearing and torque. (Would I be better served by looking into tractor/atv engines and drive trains, etc...)

Anyway, a shot off into the aether... This hull is free for the taking as I said (with another offer of a trailer that could haul it for the borrowing) and it seems like a chance not to dismiss lightly.

any thoughts or leads on the realities of this greatly appreciated.

Shoe

Bob · Post by **Bob** » Thu Sep 30, 2010 8:07 am

I've heard scooters eg the Honda Elite are pretty adaptable.

Shoeshine · Post by **Shoeshine** » Thu Sep 30, 2010 9:08 pm

hmmn, Am I right in understanding that you think a 50cc scooter engine would push 8-10 people if geared correctly?

That is almost couple thousand pounds...

Am I really overestimating what I need here?

Isotopia · Post by **Isotopia** » Thu Sep 30, 2010 9:12 pm

Am I really overestimating what I need here?

Quite the opposite.

I think you may be grossly underestimating what you'll need.

ygmir · Post by **ygmir** » Thu Sep 30, 2010 9:19 pm

I could see one of the old Honda CT 90's.....with the high/low transfer case and centrifugal clutch.......maybe geared even lower via chain drive/sprockets......

I love 'em.......I've got 2.
another question, is, what are you using for drivetrain/tires?

Shoeshine · Post by **Shoeshine** » Thu Sep 30, 2010 9:43 pm

Well I was imagining I would simply use the whole drive train from the motorcycle in the rear. bolted into the frame that will hold up the canoe.

The front end is currently on the drawingboard using a rack & P setup from an old mini dune buggy (I am trying to convince a buddy to part it out to me) Its on a tube steel frame with approx. 16" tires.

So basicly a reversed enlongated trike.

Shoe

ygmir · Post by **ygmir** » Thu Sep 30, 2010 9:47 pm

think about stability with 9 people inside.......

Shoeshine · Post by **Shoeshine** » Thu Sep 30, 2010 9:56 pm

I hear ya Ygmir...

the frame on the buggy is currently a little over 4" wide. I was thinking to extend it out another foot on each side. (just need new tie rods) so about 6'+ total

The canoe is around 14'. the front suspension would probably be around 2' from the front. the rear tire maybe a foot inside the transom. what do you think of the stability inherent in that setup?

Shoe

ygmir · Post by **ygmir** » Thu Sep 30, 2010 10:19 pm

seems, it'd be fine, as long as everyone stays put....and understands balance.

Especially with suspension, though, it'll want to lean if unevenly loaded.
and, with a single wheel in the rear, if the weight got back there to much.......

I'd sure be tempted, if hauling that many people, (not to mention that you don't know them, or, how altered and willing to listen to direction they are)
to go with 4 wheels, to fore, two aft.

wide is good, but, keep the load in mind. As you widen the frame, the span of "members" increases, and center load capability lowers.

I'm sure there is an engineering type here that knows better, but, those are my thoughts.

good luck

Captain Goddammit · Post by **Captain Goddammit** » Thu Sep 30, 2010 10:38 pm

My 25' Land Yacht cabin cruiser has about a 6-foot wide rear track, and the front wheels are only about a foot or two apart. It's stable enough to cruise the playa, so I'm sure if you have a similar track width at either end of your outrigger and a single wheel at the other you'll have more than enough stability.
Of all the possibilities to power your canoe, I think you're probably right to look at motorcycles, they're likely the cheapest and simplest way to go and have the right general configuration to fit in the canoe hull. I also think you should gear it way down... if you use a good-sized (at least 250, but I'd go bigger) unit, it's not so much for power reasons that you wanna gear down, it's because it'll be a pain in the ass to cruise it around at low speed and stop-and-go among foot traffic like playa vehicles do unless you give it super-low gearing. You'll probably also fry your clutch if you don't gear way down. If you use a "real" motorcycle powertrain, it'll almost certainly be chain drive, making it fairly simple to do something creative with the gears.
I'd find a four-stroke bike to use, it'll be MUCH more pleasant to listen to, and torquier.
I'd forget the little scooters and use a big motorcycle; you can probably scrounge up an older or wrecked one super cheap. Using a big motorcycle chassis means you'll get a sturdy rear suspension and a wheel/tire that can handle the weight of your MV full of people and an engine that won't have trouble pushing it.
It'll even have a brake that's adequate for stopping a slow-speed MV.

I'd attach it to the canoe hull by welding square tube to the motorcycle chassis, sticking straight out the left and right sides. I'd through-bolt flat metal plates to the inside of the canoe hull, and weld the square tube to that. The front end... well, I'd have to look at it... you'll figure out something!

Shoeshine · Post by **Shoeshine** » Thu Sep 30, 2010 11:58 pm

Thanks Cap. That's exactly the kind of input I'm looking for...

(real life MV exp.)

Great thoughts on driving conditions... one of the reasons I was momentarily psyched on the scooter idea was the auto transmisson. But the weight considerations + brake (never even had that on my radar) are good to consider.

...and yeah the frame is still a WIP too, dont know that I trust the structural integrity of the thing. I was sort of thinking tube from rear to front with the canoe bolted through, kind of sitting on top.

funny enough I'm going back and forth between about 5 windows, one being craigslist and just saw a suzuki "savage" 40ci (@655cc if I did the math right) and chain drive. $600 . two-banger though, probably loud as hell.

Shoe

PS. Can I use the word "torquier"... I have no idea how i will pull it into conversation but that's just great.

TomServo · Post by **TomServo** » Fri Oct 01, 2010 1:03 am

Whichever power source you use, make sure to conceal the power plant...creatively. It would be a shame for you to put in all that work, only to be denied at the DMV. Motorizing a canoe sounds like a sure pass, but just to be safe....

Lassen Forge · Post by **Lassen Forge** » Fri Oct 01, 2010 9:44 am

Been thinking on this...

Slow speed, high torque - I'd think about something like an old goldwing - the water cooling would make it easier to keep it cool at the low playa speeds you'll be doing. Gearing may be a little tricky (they're shaft drive) but then you don't have the problems of a centrifical clutch. And the whole kaboodle is sealed, and low to the ground.

Speaking of - the playa eats Centrifical Clutches for breakfast. Seen WAY too many MV's die over this. They can't handle the unstable duty cycle and excessive weights imposed on them in a usually semi-unlocked state. My plans for a MV involve a flat belt and clutch tensioner system (like the production/assembly lines of old)... IF I can get it together enough to find space to build the damthing.

I had another idea - Honda used to make a GL-650 (the v-twin silverwing) servi-car set-up... they were designed to run slowly, over long periods, water cooled, etc.. You would have both a frame setup and a dual rear wheel driven system (increased stability and you wouldn't low-center your driven wheel if the outrigger wheels hit a tall dune)... Availability and cost are an unknown, but start checking cycle salvage places, police auctions etc. Another possibility are the meter maid/cushman type vehicles.

gyre · Post by **gyre** » Sat Oct 02, 2010 10:29 am

The larger clutches start at 600 cc for bikes.
Just because you have power doesn't mean a bike is built for much load with weight.
You may succeed with a single purpose vehicle though, built for limited speed.

Consider the load on the transmission, clutch and bottom end of the engine.
A formula car may have massive power but lightweight components designed for a very light load under power.
Of note that ferrari rods are quite beefy for this type and seldom break.

Yes, you can silence a two cylinder engine, even one of 1500 cc.
I'd start with an X-pipe.

Unless there is a specific reason for using a bike engine, I'd go with a different type drivetrain.
It is often done for hypermileage cars, to take advantage of new technology or for three wheels.
There is experience in this area out there.

Shoeshine · Post by **Shoeshine** » Sat Oct 02, 2010 1:51 pm

Thanks everyone...

My primary though in using a motorcycle engine was cost and availibility. I can craigslist a wrecked bike (bent frame or the like with a still working drive train) for a couple of hundred bucks.

I am also familiar with bikes, and feel comfortable that I can modify/extend the control systems (brake and throttle cables, etc..)

I've looked at riding lawnmowers in the classifeds that are in the right kind of price range but I really know next to nothing about them.

I have seen small engines for farm equipment that would be perfect for this, but we start getting into the thousands of dollars range just for the engine and transmission. Then I have to custom build a drive train.

I would more than happy for any suggestions on anything else that would be both readily availble and easily re-purposed.

Shoe

Captain Goddammit · Post by **Captain Goddammit** » Tue Oct 12, 2010 7:19 am

I've done a couple riding-mower based BM M/Vs. Mine were old Craftsman 11-horse units, with loud Briggs & Stratton vertical-shaft engines.
They had a rear transaxle thingie, and the clutch was just a tensioner pulley on the drive belt. The belt was a standard automotive-style V-belt.
Re-gearing was easy, there was a small pulley under the motor and a large pulley at the transaxle, and I simply cut them and welded equal size old car water pump pulleys at each end. I expected trouble with the holding power of the drive belt after the gear-up, but had none at all.
I used a full-size car battery, and if I had it to do over, I'd also use car alternators driven off the motor from a separate pulley.
Mine was made to be a "BiPlane" so the B&S mower engine noise sounded "correct" but it might be a little obnoxious on a canoe.
A nice thing about using a drive belt with tensioner pulley as a clutch is if you do wear it out, it's easy to carry spares and fix it. While not ideal, I consider that acceptable for a one-week vehicle that needs to be cheap.

You'd really want to gear it up, they're just too slow even for a BM M/V. When I did, I then found the stock mower steering was designed for 1 mph and was way too sloppy at any real speed, but your canoe probably isn't gonna use the front part of the riding mower (if you go that route) anyway.

Best part: I've collected many riding mowers, always free! If you're near Seattle I still have one you can have just for getting it outta here.

Shoeshine · Post by **Shoeshine** » Thu Oct 14, 2010 12:01 pm

good thoughts Cap,

I appreciate the offer but I am at the extreme other end of the coast in San Diego. Luckily they are around here for the asking too.

Did you get enough torque to move a few people when you geared it up?

Thanks for all the input.

Shoe

Post by **mdmf007** » Thu Oct 14, 2010 7:13 pm

If I were to build this project Id trash the motorcycle parts and simply get the parts for a gokart and 3-5Hp motor with centrifugal clutch from a place like Northern tool, or any of the other online supply houses. 3-400 bucks would get you all of the mechanical parts and a warranty to boot.

Drop a PM, and ill give you part numbers and other websites.

It would be way easier to adapt, easier to control, easy on the wallet with no surprises, warranty, etc.

Bob · Post by **Bob** » Thu Oct 14, 2010 7:46 pm

Per upthread, he's building a party bus to carry ten people.

Post by **mdmf007** » Thu Oct 14, 2010 9:43 pm

Bob wrote:Per upthread, he's building a party bus to carry ten people.

I thought we were still talking about the 1200 pound unit... 5Hp is plenty, there is a speed limit on playa!

ygmir · Post by **ygmir** » Thu Oct 14, 2010 9:54 pm

mdmf007 wrote:
Bob wrote:Per upthread, he's building a party bus to carry ten people.
I thought we were still talking about the 1200 pound unit... 5Hp is plenty, there is a speed limit on playa!

I agree...........*pointing up thread*..........

theCryptofishist · Post by **theCryptofishist** » Fri Oct 15, 2010 8:56 am

*stands next to Ygmir, Bob, and mdmf, looking upwards*

What's up there? A blimp? Winged squirrel? Oh, I see, a duck wearing a telephone.

Pretty interesting.

dragonfly Jafe · Post by **dragonfly Jafe** » Sat Oct 16, 2010 11:39 am

a little rough math may help;

kinetic energy = 1/2 * mass * velocity^2

assumptions
-----------------
10 people = 2500 lbs (worst case)
vehicle = 1200 lbs (???)
= 3700 lbs total weight
max speed = 5 mph

this works out to ~8300 Joules if I did the math right, assuming a 50% loss between gearing and playa surface. That means about 11 or 12 Hp is needed.

I would bump that up by 50%-100% more, so you are not maxing out your power system to keep up speed, so 18-24 Hp should be your goal (assuming a gas engine).

Captain Goddammit · Post by **Captain Goddammit** » Sat Oct 16, 2010 6:05 pm

I'd advise NOT using a centrifugal clutch for durability reasons. It's gonna be in slip-mode a lot.
Speed isn't the issue when deciding how much power you need, playa surface condition (in other words, rolling resistance) is the issue. On a smooth hard playa, I have to drag the brakes as I roll along idling in "drive" on the boat, other years when it was very soft and silty I had to throttle it to keep rolling. That's why you need power.

I did see a really cool canoe several years ago on the playa; it had an "outboard motor" that was a motorcycle back end mounted like an outboard motor. The concept worked great! "Real" boats often have outboard motors, and this one simply had an outboard with the right type of "propeller" for the "lake" it was on. It swiveled like an outboard motor, which eliminates the need for steering at the front. If I remember right, it just had a handle with the twist throttle that you grabbed from sitting in the rear of the canoe to steer and drive. I think it swiveled on it's head tube where the forks originally were.

It was simple and worked great. The motor didn't need to be hidden, because outboard boat motors are SUPPOSED to be hanging out on the transom. There really isn't any room inside a canoe to put the powertrain anyway.

Maybe if you copy that layout you could go the extra mile and dress up the motor with an outboard motor cowl... maybe cut it in half and attach the halves to each side of the bike gas tank or something.

ygmir · Post by **ygmir** » Sat Oct 16, 2010 6:37 pm

problem solved: