Paul's commuter Ebike #1

I found this bike in the woods all messed up. I converted it to electric and use it as my commuting vehicle to work. It's very simple. No controller. Only a $4 on/off switch. Top speed of about 35-40 mph. Good acceleration. Total cost: $230

Category:

Autos & Vehicles

Tags:

• bike
• electric
• ebike
• hybrid
• bycicle
• cheap
• plug-in
• global
• warming
• chevron
• GM
• Who
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• The
• Electric
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• allan
• Lloyd

[definitionofis]

I have been studying torque mathematics and I read somewhere that the braking requirements increase at a rate of the square of the speed.

That idea makes sense because it is pulled from the notion that stored kinetic energy is a square relation to velocity.

I'm just posting this as a warning about the limits of those brakes on that bike.

You need a plan B if those hand brakes fail.

Does your new controller have a braking feature ?

[MPaulHolmes]

Brakes? I only have one working brake! hehe. You are right. The new controller for the car has lots of built in safety features so that it shuts down if something bad happens. But since this video, I've added a controller to the bike and I try not to ride on major streets. You are right.

[definitionofis]

I wasn't kidding about using the controller as a brake. If you send reverse polarity pulses to the motor it would be a good brake.

Also, just shorting the wires on a permanent magnet motor provides some braking torque as generated current flow provides a reverse magnetic force, which opposes rotation of the motor. That technique is sometimes used to slow wind turbines.

[MPaulHolmes]

Oh! Yes.  It doesn't have that. It's a weird phenomenon too. I've wired the motor wires togther and tried to push it and it is really really hard. That's a interesting idea to add it as a controller feature..

[alscompute]

how many watts is the motor?

[MPaulHolmes]

I don't know what it's rated for, but I use it at 48v, 20 amps about, which is 1.5HP. haha. I don't do that continuously though, since it's probably more like a 400watt motor.

[definitionofis]

You can also use that effect to recharge your batteries instead of just shorting it and wasting it as heat, inside the motor coils.

[MPaulHolmes]

Well, as long as you only use the motor once you are moving pretty good, an on/off switch won't draw too much power. My motor worked with the switch for about a year before I added a controller. A switch was perfect for cruising at high speed.

[ez3usx2]

oil companies do about anything to protect their business.they run the goverments banks and universities.they should be charged with treason and we can start with standard oil for selling the germans special fuel for their planes during ww2.we wont be free until we kick the oil companies butts for ruining the earth and killing people. nice bike i try not to buy any more oil than i have to.

[DVMsucks]

wellllll, the controller lets you have variable speed, it saves your battery life, and your motor will crap out in no time without a check on the power its getting.