Need help motorizing a 1963 Schwinn with a DC motor

My name is David Lunde. I am looking for a motor that, in a thus far
fruitless attempt, I have been unable to find. PLEASE TAKE THE TIME
TO READ THIS, AND ANY SUGGESTIONS ANYONE HAS WOULD BE MUCH
APPRECIATED.

Bio:
I am 16 years old and I love outboards, bikes, cars and anything that
moves. I wanted to embark on a project that would be cool and overall
silent - meaning I wanted to make something electric. So here is what
I started...

My project:
I have a 1963 Schwinn world traveler (it was my father's) and I want
to hook a DC motor to it. I did some calculations (thanks to my
physics class) and according to my calculations I produce about 2/3 hp
on my bike. Here are my numbers if anyone is interested. You can do
the calculations


THE CALCULATIONS:

1 hp = 33,000 ft*lbs/min

my ft*lbs/min = my weight (224lbs) * length of the peddle from
rotation axis to end of peddle (7 in. or .58ft) * number of times I
peddle in one minute (50 revolutions/min under uphill conditions and
at slowest speed, full weight on one foot) = 6,533 ft*lbs/min

The rear and front sprockets have a gear ratio of 3.06:1 which means I
am actually peddling with 19,991 ft*lbs/min

This then means that I produce about 19,991/33,000 = .65 or almost 2/3
hp (I don't know if this is realistic. I remember reading someplace
that humans are capable of producing 1/5 hp or so, but this is what I
got.

-I would like speed and power, so I decided on a 1 hp DC motor. This
would be more than enough for me, especially considering two special
features on this Schwinn bike. First of all, it has a transmission.
Meaning there is a 17 tooth sprocket sticking out of a cylinder.
Inside that cylinder are three different gears. Lowest gear just
engages the outside sprocket and 2nd and 3rd gear engage gears inside
the transmission. So if I get this thing working I would be able to
shift gears by disengaging the motor and shifting (pretty cool).
Second of all, (this isn't really a function of the bike but...) I can
gear down the sprocket so I would need less than 1 hp but I want
power. Mounting the motor and future 12VDC car battery holder will be
no problem. Procuring a motor is my problem.

My Project PROBLEM:
-I can't find a flippin' 1 hp 12VDC motor for less than $400!! I
don't have that money! My first thought of solving this problem was
to use a starter motor from a V8 engine. If it can turn a fly wheel
in winter I would hope it could push me up a hill. So I went to a
junk yard and found many starter motors, but the motors (or all the
ones I've seen) have the bendix and the motor cast as one piece of
aluminum. Because of this I can't remove the bendix for fear of there
being no bearings left for the motor (I believe the bearings are cast
into the aluminum). Not only that, but the starter motors are NOT
made to run continuously. If they heat up it can melt soldering,
casting and whatever else is near. So that ruled that out...
The great thing about finding it at a junk yard was it was cheap.

What I need:
I NEED A 1HP 12VDC MOTOR THAT WILL RUN CONTINUOUSLY FOR CHEAP. I am
not very rich. If there is an older style car that someone know about
where the bendix and motor are separate I would be willing to look at
that, but I would rather have a continuous running motor instead. So
if there are any suggestions, please please please e-mail me or
respond back to this. All would be much appreciated.


Thank you for reading this and for your time. There are a lot of good
brains to be picked on the Internet.

Any questions just e-mail me or respond to group. I will look daily
for responses.

Sincerely,
David Lunde

In article ,
says...

My name is David Lunde. I am looking for a motor that, in a thus far
fruitless attempt, I have been unable to find.

I wish I knew where to tell you to look, because
there have been such motors available for bicycles
for many years. In fact, when I was a kid, way
back in the 1940s, the boy next door had one of the
first "English" bikes I ever saw - skinny tires
and a 3-speed gear shifter. I had the usual old
balloon-tired single-speed clunker. One day he
miraculously asked me if I would like to swap bikes
with him since he'd purchased an add-on motor
and it wouldn't work on the skinny tired English bike.
Of course I was ecstatic.

I've seen similar motors advertised in very recent years.
Typically they are designed to roll
onto and off of the front tire and have rubber
rollers that grip the front tire and thereby add
thrust. I'm not sure where the battery pack goes.
Or maybe they use small gas engines - I can't remember.
There are the gasoline engine "motor bikes" very popular
in Europe and other parts of the world that have
pedals along with the small engine. The engine is
started by pedaling momentarily. Good luck with
your project.

"Cal Dia" wrote ..
........I'm not sure where the battery pack goes.
Or maybe they use small gas engines - I can't remember.

There was a kit available after WWII whereby a very small 2-cycle
engine attached to the handlebars and ran against the front tire.
Called a Whizzer. These made a brief comeback during the gas shortage
in late '70s (?). A competitor engine was also available and even a
complete Whizzer bike. The market went to minibikes instead.

Hi David

I've had several electric bikes over the years, most of them used what
we call Pancake Motors, but they can be changed to drive the gear
instead of using friction against the tire.

Although the newer Hub Motors sound good, they eat way to much juice
which makes them basically worthless.

You sounded like you were wanting to drive the bike by using the pedal
gear as the connect, that's not a good idea.

My best bikes used pancake motors, but instead of driving the tire, I
installed a regular small pulley on the motor and a very large pulley
to the bicycle wheel, the large pulley measured two inches less in
diameter than the bicycle wheel excluding the tire and actually
attaches to the ferrules the spokes screw into. Uses a belt instead
of a chain so you can use the existing drive system, only in reverse
of the way it was meant to work.

I have fooled with various starter motors, they draw a lot of current
and get real hot real quick, but salvage ones are cheap!
You don't have to worry too much about the Bendix just lock it in the
engaged position either buy using a spacer or a spot weld to keep it
in place.

If you keep your eye on yard sales, often you will find motorized kids
toys on sale, usually broken, for real cheap. These are often only
250 watt motors and you need about 400 watt motors for a good bike.
But two of them mounted such that the belt can run across both of them
will give you just under a full horsepower and sometimes more,
depending upon the toy it came from.

Just for grins we collected several cordless screw drivers once and
after removing the gearboxes and installing small pulleys we mounted 8
of these things in an arc over the back wheel.
We were quite surprised, that bike would climb a hill like a mountain
bike. We probably could have gotten by with only 4 of these little
motors. Our rheostat was bad so you had to lean over the handlebars
to take off or it would dump you over backwards. When working with
more than one motor, theres no using a slipping belt clutch system, hi
hi.....

Good luck with your adventure!

TTUL
Gary

In article , says...


Called a Whizzer.

That's the gadget! Thanks for the memory.

In article , says...

Called a Whizzer. These made a brief comeback during the gas shortage
in late '70s (?).

Here is a great article that discusses the "comeback"
and the companies that produced/sold the "strap-on" motors,
and why they no longer do so.

http://www.users.globalnet.co.uk/~pa...cc/arc0394.htm

"Cal Dia" wrote ...
Here is a great article that discusses the "comeback"
and the companies that produced/sold the "strap-on" motors,
and why they no longer do so.
http://www.users.globalnet.co.uk/~pa...cc/arc0394.htm

Thank you thank you thank you.
When I was a youngin I wanted to put a motor on my bike so bad I lost
sleep trying to design it. A friend of my father mounted a
conventional horizontal 4-cycle single cylinder engine on his bike and
was having a ball.

During the gas shortage I was walking to work and would see a swarm of
these Whizzers and related types buzz by sounding like steroid
mosquitoes. Envied them much.

In article , says...

Thank you thank you thank you.

My pleasure. Here is another web site that I dredged up.
I'm not sure that this "Spitfire" bike is any better than
the average "Mo-ped" but it's a good example of the type
of engine that uses the crank of the bike as the crankshaft
for the single-cylinder gasoline engine. I've had the
good fortune to travel much of the world in my lifetime,
and the "Mo-ped" type of bikes are very popular in much
of the "third world" as well as more developed countries
in Europe.