Electric bicycle time

[DeathBlade556]

Well I'm bored so a new project, adding a electric motor to my bicycle I picked up a 2000lb winch from harbor freight on monday and I took it the machine shop at RMU yesterday before the baja meeting and ripped it apart, cleaned the brushes, drilled some vent hole, milled out the bottom and hooked up a tach to it. At 24volts I got some 3400rpm out of it I'm going to use a 10T sprocket on the motor and a 48T on the rear wheel for a 4.8:1 gear ratio
I'm going to mount the motor above the rear wheel and attach the 48T sprocket to the left side of the hub opposite of the normal gears.
like this


27" rear wheel (cir 84.75")

3400 / 4.8 = 708rpm

708rpm * 84.75" = 60,003"

60003" / 12" = 5000.25"

5000.25 / 88 = 56.8mph

[Ragnorox]

your my hero

[Muzikman]

Wait...no Paint CAD drawings yet?!?!?

[Cebby]

Does it have a free spool function? What's the duty cycle on the winch motor?

[sb406]

It'd be really bad ass if you set it up for regenerative braking.

[92YJCBG]

is it going to be time travel capible?

[jackb1]

is it going to be time travel capible?

Looks like it will only do about 57mph. That's a little short of the necessary 88mph for time travel. Duh

[SirFuego]

A motorized bicycle!! You should patent that idea and make millions!

What are you doing with the pedals? It'd be sweet if they could be used to charge the battery. Are pedals going to still power the rear wheels if the motor takes a dump -- sorta like how an escalator still "works" even when it doesn't. Or are the pedals just going to be for bling?

I always get a big smile on my face when you start one of these threads.

[jeepxj3]

A motorized bicycle!! You should patent that idea and make millions!

What are you doing with the pedals? It'd be sweet if they could be used to charge the battery. Are pedals going to still power the rear wheels if the motor takes a dump -- sorta like how an escalator still "works" even when it doesn't. Or are the pedals just going to be for bling?

I always get a big smile on my face when you start one of these threads.

Its been done before, its called a moped! Electric has also been done before, its called Bionx
http://www.greenspeed.us/bionx_motor_bike_kit.htm

[Macabre]

sorta like how an escalator still "works" even when it doesn't.

http://www.comedycentral.com/videos/...-wall-knocking

Man, I miss that guy.

[r6cyclegal]

I have something like that. It's called an R6.

[2002wranglerX]

Does it have a free spool function? What's the duty cycle on the winch motor?

huh, ya for pedaling that could be a problem if not.

[DeathBlade556]

Well I'm mounting the 48T on the rear hub and I'm keeping the pedals so I can pedal when I need to. The rear gears will free spool when I'm usingthe motor so the pedals won't be turning(and ripping off my shins) like on my last protoype, the the motor will turn when I'm pedaling so if I can find or make the right controller I should have regen braking. Its just finding a circuit which can do PWM at 24V and 120amps.
As for the duty cycle its more of 'is it hot yet?' when I'm done adding the blower for cooling it will take a while longer before I get to 'is it hot yet?'

[Bill]

I have one question...

Where the hell do you come up with this stuff?

[BigDukeSix]

I think you should invent a velocipede that combines an internal combustion engine that powers a mobile platform with four wheels and steering. You could call it a "car".

[DeathBlade556]

Since there was on electricity at RMU I went home and worked on some projects, the super paper shreader is coming along nicely, the windturbine v2 is in need of a good PM DC motor to use as a generator and the Ebike tried to kill me.

I had attached the sprockets to the motor(12T) and bike wheel(48T), then broke the chain and got it tentsioned. The psychotic vibrations that threated to fip the whole think though the air were manageable at 12volts then stupid me decided to wire in the other battery for 24volts. Bad idea. It seams that 1/8"x3/32" derailleur chain
cant stand the motor output at 24volts, 156amps x 24volts = 3744watts = 5.02HP

It ripped the chain off of the 48T sprocket and snapped the fix link I was using to hold it together, it got jammed on the 12T and it went flying around like some unholy weadwacker till the motor spooled down.

Note to self bicycle chain is not for power transmission.

I got a 9T #41 sprocket and chain on order from grainger and an 56T on the way from ebay. Lets see this thing break that.

[DeathBlade556]

I got the 56T sprocket, it took forever to get it on straight. put the wheel back on and its way out of balance anybody got a way to balance a bicycle tire.

[Jpdst29]

i didnt even know there was a way to balance a bicycle tire. or that anybody did such a thing.

[BAD_GNR]

anybody got a way to balance a bicycle tire.

Most people have it done professionally, but all you really need is a spoke wrench and a lot of patience. Just throw the wheel on the bike frame and spin it. Wherever it's rubbing you'll need to tighten or loosen 5-6 spokes depending on which side you need to pull the tire. Just keep adjusting them and spin the wheel to get an idea of your progress. Just make sure nothing gets over or under tightened. It takes a while.

[JeepSteeler]

Why don't you try belt drive instead of fooling with the chains/sprocket?

Lord knows you already ripped both shins off, I'd hate to see that chain get ahold of you.

This might be the first thread of yours I've been able to follow *almost* the whole way (patting my back)...

[abrzrkr]

Most people have it done professionally, but all you really need is a spoke wrench and a lot of patience. Just throw the wheel on the bike frame and spin it. Wherever it's rubbing you'll need to tighten or loosen 5-6 spokes depending on which side you need to pull the tire. Just keep adjusting them and spin the wheel to get an idea of your progress. Just make sure nothing gets over or under tightened. It takes a while.

That's how you would straighten the wheel. Now if you want to balance it I would start by taking off the reflector.

[Backwoods Couple]

I think it's pretty. That's about all I can get from this.. Oh.. and slightly insane!

Diane

[DeathBlade556]

Finally got to working on my bike project(have a wind turbine project going), I took the #41 chain and found my ebay sprocket is not #41 like the chinese claim but some kind of odd size I took it to the local bike shop its not metric chain, is not ANSI, its not bicycle, its some, 'we are china!, we have no quality control!, who cares that size the teeth are! its only going to spinning at high speed." size. But we found a BMX type chain fits it ~ok~ probably wont come flying off.
After that I took the 9T to the machine shop at RMU between classes friday. Turned it down to fitt the BMX chain.
Was bored after my OBA explosion so I fabbed up a crappy frame from some 3/4" angle and 1/2" tube.
One of the engineering professors is looking over my controller circuit I'm basing it around a 1200Volt 300amp IGBT.

[Bill]

but will it wheelie?

[DeathBlade556]

It might, If I run it at the stock amperage of 140amps and at 24volts its should be 3360watts / 764 = 4.3HP if I take it up to 36volts thats 5040watts / 764 = 6.5hp!!