Hello All. Showing off and input needed

I spent at least 8 hours reading this forum upon discovery. I am very impressed to say the least.

I have a few active EV projects that I would like some input on:

The E-bike is currently a 24v 10amp WE brushed motor on a I belive steel frame (because it responds to a magnet). As the frame is a $60 walmart frame and I do not know exactly what the frame/forks are made out of, I am wondering if I should trust the forks with the 36V WE controller (36v 600watt??). Also the brakes suck (what are they called when the grab with a cressent from the top?).

The next project is a go motor board 1500 that crapped out. I just thought I'd share its progress. It's a mix between goped hardware, gomotorboard hardware, and random computer hardware (gutted rackmount hub, brackets etc.)

Hi Smoker, welcome aboard. You are right, there is a lot of talent on this forum. I don't contribute much, but sure enjoy it.

I started with a $53 Wal Mart MB when I ended up with a trashed 24v scooter. After burning out the scooter motor, I set the bike up with a WE BD36 and it worked out pretty good. The brakes were lousy also, but I eventually got some pads that worked better, but were noisy. I needed more power and the ability to carry stuff, so I ended up with a power trailer on the MB, giving me 3 BD36's (one on the bike, two on the trailer). Then I fell in love with a recumbent trike and set it up with 3 WE BD36's just like the MB, but all 20" wheels.

Moral of the story: Start by spending a couple of hundred dollars, and end up spending a couple of thousand dollars. But it sure is fun.l

Hi Smoker:

Your current setup should produce a maximum of about 200 watts. Which isn't too powerful. I'm sure you have to pedal most of the time.

The formula for power is

Power = current * voltage = 10 amps * 24 volts = 240 watts

However, motors are about 80% efficient, and there are some mechanical losses too, so maybe you're getting 200 watts.

If you upgraded to 36v it would be more likee 300 watts. But you could probibly run more current too. I don't know what that hub can handle, but I'd run some more serious current through it and see what happens. See if it heats up.

I don't think you'll have a problem with the forks with your current setup.With a $60. Walmart frame chances are it's all steel. If you were to bump up to 36 volts which your controller will allow you'll improve the top end speed and still not have issues with the forks I would think.

Fork issues tend to arise with suspension forks (which it seems your bike doesn't have by looking at the photo)or running a Crystalyte 5xxx series motor in a front fork as the torque attained with these motors can rip them out of the dropouts.

Eric

Welcome aboard,
Is that box on the GoMotorboard all batteries? 50 mile range?

WE has an upgrade kit that converts their BD24 to a BD36 that includes a new throttle, controller, and an additional battery. That leads me to believe that just adding a battery may not work. But even if it did, you would be limited to 10 amps, whereas their BD36 controller goes up to 35 amps.

Beagle123, why do they call the BD24 a 400 Watt system when it is only ~240 Watts (depending on battery charge) at 10 amps, but they call their BD36 a 600 Watt system when 36V X 35Amps = 1,260 Watts?

Sorry,I thought Smoker was running 24 volts with a 36volt controller,which would allow for another batt.

Guess I read that wrong...

Eric

Thanks for the input guys

I bought the 36v/35amp controller from WE. I saw somone here running theirs at 48v. I could connect a 40mm fan for cooling. Is this adviseable?

Yeah the gutted network switchbox will house the batteries. I plan to put 4 12V 20AH SLAs in it. It's 11 teeth on the pinion and 56 teeth on the 6" tire. Motor is a 250w 3000RPM Max. How fast do you think i'll go? 15mph?

Also, I am thinking about buying a quantity of brushless 400 watt hubs, do you think $115 ea. shipped. is this a good price? (not the kit. just the hub and spoke/rim assembly)

On a steel front fork, 48 volts is the max I would put. In my experience and about 3 trashed front forks, 48 volts appears to the magic number. Anything more and I always seem to split even the strongest steel bike forks.

Rassy said:

Beagle123, why do they call the BD24 a 400 Watt system when it is only ~240 Watts (depending on battery charge) at 10 amps, but they call their BD36 a 600 Watt system when 36V X 35Amps = 1,260 Watts?

Click to expand...

I'll give you my best guess as I understand it:

I beleive that the hub motors have a rating for continuous usage of 400 and 600 watts. That means they can handle those type of power outputs without overheating. Its up to you how much voltage and current you want to pump through them. If you run 24v, 10amps through a 400 watt motor, you'll just be getting half the performance from it (200 watts). You could safely upgrade your controller to 20amps (400 watts), and the motor should handle it. Also, if you ran a continuous 35 amps through the 600 watt motor, you'd get a smoking motor because it can only handle about 20 amps too (at 36v).

I run a 750 watt motor at 36v, and many times I hit almost 30 amps of current through it (1100 watts) on hills etc. Howver, I can't do it continuously. I can only push the motor that hard intermittantly, like on hills.

Motors simply run the current through windings of copper wire to pull the shaft, so you can hook-up and voltaage/current setup you desire. So when a motor says 36v on it, it just means that it is "tuned" to run at 36v. You can still run it at 48v, it will just be slightly less effecient.

Thanks Beagle123. your explanation makes good sense.

"because it can only handle about 200 amps too (at 36v)."

I think you meant 20 amps in the above.