# Electric Motorcycle

1. Sep 4, 2010

### ƒ(x)

I've been trying to think of a hobby and stumbled upon the idea of constructing a motorcycle. The catch here is that it would have to be electric--I hate having to use gas stations. I would only use it for commuting to school (a little over 2 miles each way) and in-town driving (who knows, anywhere up to 10 miles each way). But, I live on a hill that is fairly steep, so the motorcycle would have to be powerful enough to handle about an 8 to 10 degree incline for about 1/4 or 1/5 of a mile. Even though I'd stay close to home, I'd like to make it go as fast as possible.

Now, the most difficult part of this will undoubtedly be the power supply. Lithium battery packs are probably the only things I'll be able to obtain--I'm using my own money for this, so the budgets pretty low.

Before I plunge head-first into this project, I thought it would be wise to get the opinions of some science minded people.

One last thing, also before I start I'd like to have the math worked out (engine output, power requirements, braking, maximum weight, all that stuff). I don't know any formulas outside of the ones from my high school physics class and don't know if those are applicable to this situation.

2. Sep 4, 2010

### cronxeh

What is your budget? I got into Lithium-Iron-Phosphate batteries (LiFePO4) and they seem to be the highest capacity batteries you can get. A small 20 Ah / 36 Volt pack would run you for 350-400 bucks. You would need about 4 of these for a 50-70 mile range

3. Sep 4, 2010

### ƒ(x)

If I really got behind this and decided that it would be a good idea...about 3k, maybe more.

I'm also concerned about safety, since its a motorcycle (I live in the US, people here drive like idiots)

4. Sep 4, 2010

### cronxeh

Yeah you better drive fast, I don't break for scooters

5. Sep 4, 2010

### ƒ(x)

hahaha. Is it possible to make an electric motorcycle using items available to your average consumer that goes 80 mph?

6. Sep 4, 2010

### cronxeh

Yes! But if you can get it to 88 mph you can travel back in time and tell yourself to study hard, get a job, and buy a car

In all seriousness, yes you can get it up to 90 mph with right parts and design, but for a rather short time. How short a time and all the needed calculations are rather time consuming and expensive and unfeasable to even ponder about. I would not recommend riding around on a scooter faster than 30 mph.

7. Sep 4, 2010

### ƒ(x)

I take it you arent a motorcycle fan

8. Sep 4, 2010

### cronxeh

I am, but you must be suicidal to want to go 90 mph on a scooter that you are going to build yourself with high school physics knowledge. Are you going to include breaks on this thing?

Watch this hilarity at 3:25 onward:

This dude, stretched out flat on the ground, is epically hilarious.

9. Sep 4, 2010

### ƒ(x)

I was going to strip down a gas powered one and replace the motor with an electric one and put the batteries where the gas tank was.

10. Sep 4, 2010

### cronxeh

OK but how are you going to connect the motor to the driveshaft? Chain? Or how about having the motor built into the wheel? Its going to get very complicated, needless to say tolerances for errors are rather small. This thing will almost likely fail and stall or have the chain ripped off and cut your leg.

My advise to you, forget motorcycle concept entirely. It sucks in the winter, it sucks in the rain, and it sucks under a brick falling off a building. Rather try building an electric powered batmobile. Start your concept around the safest most comfortable bucket seat you can imagine with double seatbelts and crash gate, then put that on an alloy frame, no backseat, just a fireguard cage for 200 pounds worth of LiFePO4 batteries, and all that enclosed in a Porsche Boxter looking exterior, sport breaks, sport suspension, front and side airbags, air conditioning system, liquid cooling for the motor, trunk space.

Hey while you are at it, why not enroll in Mechanical Engineering program?

Last edited: Sep 4, 2010
11. Sep 4, 2010

### ƒ(x)

Really?

12. Sep 4, 2010

### ƒ(x)

damn...i really want an electric bike

13. Sep 4, 2010

### cronxeh

14. Sep 4, 2010

### ƒ(x)

I'm 17...can't do a mech program

15. Sep 4, 2010

### Topher925

My advice is just to start out with a small electric skooter and try to keep in under 5kW. When you start going over that power limit things tend to get complicated, dangerous, and expensive. Also, 3k isn't really much of a budget to build an electric skooter that works well but it is a place to start.

16. Sep 4, 2010

### ƒ(x)

3k was more of a lower boundry..if I take the time to do this--I'm thinking car/go-kart kind of thing now--I'd want it to be good.

17. Sep 4, 2010

### Integral

Staff Emeritus
From an article in the Sept '10 issue of Pop. Sci. the current state of electric motorcycles.

http://www.motoczysz.com/main.php?area=home" [Broken]

Last edited by a moderator: May 4, 2017
18. Sep 4, 2010

### Ivan Seeking

Staff Emeritus

19. Sep 4, 2010

### Ivan Seeking

Staff Emeritus
You know, I think I might have to do a 4-wheel drive version of that go-kart. That looks like just tooooooo much fun!!! Course I'd probably never be able to get it away from Tsu. :grumpy:

20. Sep 5, 2010

### ƒ(x)

Ok, so everyone i've talked to thinks that a motorcycle is a bad idea. But, I really want to build something--anything that helps with college applications would be great, but a car is my primary focus right now.

I'm quite new to this, in case you couldn't tell. Any tips?