about electric motors

Facts

Regenerative braking usually requires a hub motor, as most chain drive setups do not transfer power from the wheels to the motor(or your peddles). There is no regenerative riding, only braking. If you peddle against the braking, or have a gas engine work against it, or you are motor braking down a hill, that would be "regenerative riding", but it's all braking. Also, anyone who says electric is slow is misinformed. http://www.youtube.com/watch?v=WKAMus3oSdw Granted, that is an expensive setup, but brushless motors with lipo batteries can be faster than gas. One last thing, electric motors do NOT make max torque at stall, however they do make max torque early in the rpm range. And one last nice rule of thumb I like, an average person peddling makes 250 watts.
 
The only thing that gas has over electricity is the initial cost is lower..
However, over time, the electric bike is cheaper.
My current setup allows for 80miles distance @ 20mph.
Any faster or longer distance, buy a motorcycle...
My cost is ~$1500 for the bike.. Yes, it takes 3 hours to "refuel" from "empty" but trust me, after 80miles you NEED the rest.
 
I hate to disagree ,But

The main problem with electric powered bikes is the fact you just can't store that much energy in a conventional battery as to the chemical power in gasoline. Granted that they do make high storage low weight batteries for laptops and cel phones,but even they are not even close to the power per weight of a ounce of gasoline.

I looked up electric bike when I first was looking at getting a commuter going. The best thing I could find would not serve my needs. Motor bicycles are noisy,they rattle,they smoke and pollute, but they have the ability to go a long way at a reasonable speed for a reasonable cost.

mike
 
The only thing that gas has over electricity is the initial cost is lower..
However, over time, the electric bike is cheaper.
My current setup allows for 80miles distance @ 20mph.
Any faster or longer distance, buy a motorcycle...
My cost is ~$1500 for the bike.. Yes, it takes 3 hours to "refuel" from "empty" but trust me, after 80miles you NEED the rest.

I'm running ICE powered bikes but those kind of performance numbers are certainly getting into the ballpark for me with an electric.

As to cost, after toying with an HT engine some years back I moved on and come to know decent gas powered bikes/engine set-ups are gonna run a $1000 anyway so your number on that is not out of line. Good news!
 
As exhibited at the Tuscon Death Race, electric technology is overtaking ICE power with great momentum. Using the electric push in RC aircraft as a catalyst, many homebuilders are seeing much greater gains I'm power and torque than even the 2 strikers can reproduce. Paul's bike was putting out 4.5 hp, but with the linear torque curve of the electric motor, he was able to accelerate as fast as Alex on his 10 hp Morini. He also had about a 25-35 mile range and his bike only weighed about 50 lbs. He can then recharge in about an hour or two and only spend about $.10. If one was a fabricator, he could reproduce Paul's setup for less than $1500. His ride was also fairly conservatively run, he could probably pump 2 or 3 more horsepower through his system before things began to break.

I love the motored bikes, especially te old flat tracker style, but electric will always win out when you need a little peace and quiet.
 
peace and quiet

Your right about peace and quiet. the bike will not make a sound while you are waiting for the battery to charge. How many hours is another matter. As for the range of the bike, my little motorbicycle will go about thirty eight miles an hour for about sixty miles on a tank(half gallon of super)

Granted all of the other problems I brought up with internal combustion are true. But its still a grate way to store a huge amount of energy. And yes I know that most of the energy that you expend when you burn gas actually goes out the tail pipe in the form of wasted heat.

mike
 
I am about to get a system going with an electric motor. I am going to use a 24v brushless here: motor http://www.alibaba.com/product-gs/266907604/electric_tricycle_motor.html or something similar. should draw around 15 amps. at 12v or 9 amp at 24v. That is only a guess on my part. I am gearing it to go 20 mph max. 12v battery has around 100 amp hours. 100/15=6.6 or 6.5 hours. 6.5 * 20mph = 130 miles 100/9=11 11*20=220 miles.

Cut that number in two for battery sake gives 65 and 110 miles as a minimum and pedaling also would give better results. Am I way off base here.

I know the batteries are draining faster than the 20 hr rate but stop and go traffic so it is not constant. Who can ride for six hours without stopping anyway. I think the speed is going to be a lot slower 20 mph is rather fast for in between stop lights.

Dan
 
A 12v 100AH battery is going to weigh about 60lbs and the motor is going to pull more like 40a at 12v, and the usable ah of the battery is 60ah, so figure 1.25h running at 20mph = 30miles actual.
 
Besides that, can you think of anywhere on your bike you would want yo strap a 60# battery that is at least 8 inches wide? You're gonna fry that motor at 12 volts too. I appreciate your enthusiasm, I was the same way when I wanted to build my first bike. Try this website:

http://www.peltzer.net/ebike/

A lot of good information for consideration here.

The easiest way to get into ebikes is with a Hub motor. You should be able to get a full kit sans batteries for about $250. If you are interested, pm me and I will send you a link.
 
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