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[motogrunt]

Hello there,

I've been recently inspired to build my own electric motorcycle...but i'm not wired (pardon the pun) for electrical work.
Anyone here want to give me a run down or a link to a solid website that can explain to me how to match an electric motor to batteries (numbers wise). I have a general idea, but i'm lost on the values of watts and volts and all that.

on another note. how would one add in a charging unit? Are the batteries simply wired into it or is there something else?

last thing..does anyone have a good suggestion for a motor? my wish to to get at least 90mph out of it if possible.

thanks for the help. if you have anything else that yout think i would know before continuing, please let me know

[Fran K]

Hello there,

I've been recently inspired to build my own electric motorcycle...


on another note. how would one add in a charging unit? Are the batteries simply wired into it or is there something else?

 if you have anything else that yout think i would know before continuing, please let me know

Batteries are made up of cells and other stuff.  I can see how to buy the cells in my ktm freeride battery but to actually build the electronics in there as well?  I think it has about 7 connectors to connect to the charger.  The public charger down at the town hall might have 5 or there about connectors.   There must be some trade off whether some functions are put in the charger or in the battery.  There are a bunch of cells in series and in parallel dc at the battery exit while some sort of phased current must go to the motor, see three wires in that Ducati prototype on here lately.  I took apart a Husqvarna battery pole saw lately, same thing 3 wires going to the motor.  You are looking at a modern brushless motor?

[motogrunt]

I'm going to use a ton tesla batteries (18650 batteries from Panasonic). So i'll be wiring in everything myself. And yes, I was looking at a brushless motor

[NEW2elec]

Well I've put my foot in my mouth before by reading just a few posts and underestimating members skills, but you won't get many replies same as everybody else who does this type of post.
It's like going to a doctor's forum and asking how to do a kidney transplant yourself, on yourself.

It's a lot of things working together, controlled by a master program with safety limits that keep you from catching on fire or flying into a wall or loosing power on the highway.

Learn all you can about what makes the bikes that are out now work.  What their operating voltage is what size controller they use how they handle heat and what kinds of chargers they use.
In the not too distant future I think components will be more standardized and plug and play ready but right now what you can put together won't come close to Zero or Alta or Energica

Good luck and please look around the forum at all the info already out there for the taking.

[T.S. Zarathustra]

You have a lot to learn. I'm an electrical engineer and I don't have answer to all of your questions. Some Chinese websites offer motor and controller as a kit so that solves some off your problems. But you will have to mount all this in your bike, which is different kind of engineering.
As for "watts and volts and all that". Here is the oversimplified version. 750 watts are roughly equal to one horsepower. To go 90 miles comfortably you need up to 20 hp. Batteries need to provide enough Watthours to provide power for the distance or time you want to use the bike. Watthours is Watts usage over one hour. Voltage is the pressure that pushes electrons (that is called Amperes) through the motor and causes it to rotate. Voltage and Amperes multiplied together equal Watts. You can have same Watts with either high Volts and low Amperes or low Volts and high Amperes. High Amperes need thick heavy wires, high voltage needs bulky insulation (and is more likely to kill you if you touch the wires). Look at electric bike as chemical, to electric, to kinetic, energy conversion and remember that no conversion is 100% efficient.
My advice is, be careful and start by buying an fire extinguisher.

[motogrunt]

and this is why i love forums. thanks for you hlep. that's what i was looking for. I have a general idea and have messed around with electronic stuff before. just not on this level. once again, thank you for your help and advice