48V Electric Flat Tracker

About a year ago, my dad and I had the idea to convert a beach cruiser bike into an electric motorcycle. We purchased the bike and all the parts necessary and got to work. We modified the frame and rebuilt the bike from the ground up. When we finished, we were extremely satisfied with the results - a 48 volt, 15 horsepower board track racer.

Step 1 The Components

We started with a Felt beach cruiser because it had the right look. We wanted a beefy bike that could fit all the components. The goal was to keep the center of gravity as low as possible. Here are the rest of the main components we purchased:
- Briggs and Stratton Etek motor (now discontinued)
- Alltrax AXE 300-amp programmable controller
- Magura 0-5K ohm twist-grip throttle
- 4 x 12V, 21Ah sealed lead acid batteries
- Avid BB7 mechanical disc brakes (160mm rotors)
- #35 moped chain
- 13-tooth drive sprocket
- 66-tooth rear sprocket
- big power switch
- 300-amp fuse
- 8 1/4 in. stainless steel motor mount (this replaces the original bottom bracket)

Comments

[1up]

Without a doubt, the nicest electric bike I have ever seen. Amazing work.

[iminthebathroom]

When I talk about instructables to people, I use examples of exceptional work to illustrate it orally to them, yours is one of the ones that tops the list!

[rangerweavere]

With the amount of speed that you claim for the EV-12 to reach you would have to get it registered as a motorcycle or risk the possibility of large fines and possible jail time.

[woodstockbirdy]

God you are stupid. It's a bike, thats electric. No where does anyone say you have to get it registered as a motor bike. They sell commercial ones all over the world, and the don't have to get theirs registered and they go way faster.

[rangerweavere]

No that would be you.
Once you hit 60cc's then its considered a moped.

[woodstockbirdy]

Well, I guess I'm in Canada and they don't have to be registered, but I don't know in the US.

[lloydrmc]

In my state it's 50cc and 30mph, if I recall correctly. I don't recall the regs on electrics. I have read that they go by speed, (either what it will do by itself, or the speed it assists you reaching if you are pedaling), and they are very strict.

[mookiex4]

Well actually in my State at least. If you leave the peddles and crank on it, they consider it still a bicycle and would be legal. Bicycles already have to obey the rules of the road just like cars. That means remaining under the speed limits and obeying all other traffic laws for the state. The only thing you wouldn't have to do is register it as a motor vehicle. If you look at most of the videos on youtube and such the bikes have digital speedometers on them.

[lloydrmc]

Oh, please - "jail time"?

[woodstockbirdy]

I agree.

[Super Cronk]

It depends on the laws of your state. I know in North Carolina you don't have to register a bike that's under 50cc. However I don't know how electric bikes are covered there. You do raise a good point though. You want to make sure you know the laws where you live so you don't get yourself in trouble.

[kbales]

For most US states the limit is 50cc and/or 2 bhp. So electrics would be limited to that 2 horse power range.
Many of those states also require that the top speed be either 30 or 40 mph but it looks like this thing may be doing better than that.

[isaacwilk]

If you're not driving on roads you don't have to register anything.

[woodstockbirdy]

Even if you were on roads you would not have to register it.

[lloydrmc]

There's a specialized registration in my state for motorized bicycles.

[ComixDude]

i am sure someone already asked but, how do you charge them ?

[Pengwin3]

Well, it runs off of 4 12v batteries, so you could just hook it up to a car battery charger.

[The MadScientist]

How many watts is your motor?

By the way nice bike.

[The MadScientist]

How many watts is your motor?

[AudioMaximus]

I think I just found my summer project...
My design however will have no welding, since I don't own welding aterials anyways. I'm thinking of using a motor from a lawn edger that I don't need anymore. i don't know if it will be enough horsepower (probably about 3-5 hp), but it's worth a shot. If it isn't I can always get a better one from a friend for a good price.

[fmadwid]

Where can u get a rear sprocket with 66 teeth. Can't find that anywhere. I've everything else but that.

[fmadwid]

I live in Canada, Ontario and can't find a Felt here. Does anyone have one willing to sell me?

[geminitriplets]

Are the brakes sufficient for your bike? It seems that the increased weight and the speeds you can achieve might be too much for ordinary bicycle brakes.

[hayme]

Well that sucks. in my country i cant buy parts like this. Is it possible to make some kind of a Tesla turbine placed on this? or if i can salvage some kind of a powerful fan engine or a boat engine, can i still put it in? what are the possibilities that if i did not follow your components, i am going to explode and burn?

[Radioactive_Legos]

I figure as long as you have a source of power that fits and that you can control, you should be safe(ish).  But always use your best judgement, and if you don't feel comfortable, don't do it.  Tesla turbine would be hard to adapt for use on something like this, though.  High RPM and low torque would have to be geared way down and you'd lose a lot of efficiency doing that.  Plus you'd have to supply some sort of fluid under pressure to keep it running.

[hayme]

goddamn dude! when you said safe(ish) it feels like if i do it my way i am going to be like a taliban chopper with with paul bin hamad teutel sr. ok dude thanks for the advice and imma show you my stuff before i try to run this thing and hope for me not to go BOOM!

[pie R []ed]

What's the range like on this?

[Machine]

That is really a nice job. It looks very well made and has got an interesting 'steampunk' kind of look to it. (see Google images for an idea of that).

Don't stop at one, perfect the design, make a few of them and sell them, you have the skills.

Expensive battery-sets are one of the major problems with electric bicycles. SLA batteries are the cheapest, are commonly available and electric bike lovers will like that when their batteries die. They can get cheap replacements and easily.

Personally, I'd like to see more of a steampunk look, but that's just me... hahaha.

[Aron313]

NICE!

[Gunther45]

Ever think of Painting it. It has an Early 1900's Indian/Harley look to it. Give it an early retro/steampunk paint job and I guarantee you could sell these things. The point is just to make it but Just saying. A++ on the bike though.

[Matt Carl]

How did you cut the aluminum and attach it to the bike?

[red9er]

i assume he just cut it w/ a metal blade for a jig saw or band saw.
as for attachment i can see metal screws or bolts just above the batteries on the 2nd picture that attach to the frame.

[Super Cronk]

What kind of range have you been able to get on this?

[Davidfromcali]

If that really puts out 15 horsepower it is way too much power for a bicycle frame, chain, brakes, and wheels. That would be enough to hit over 60 mph. Extremely dangerous. Simply becuase the parts fit doesn't make it safe. Crazy.

Nice looking.

[FurtherThanTesla]

I want to make a solar racer with that motor setup, and was wondering- Whats the gear ration on the sproket and motor? and how much was that particular motor?

[LiquidLightning]

13 tooth drive/66 tooth wheel sprocket. 5.08:1 ratio.

[PyroBuilder15]

The new version of it is about $450 USD, i found it here, http://www.robotmarketplace.com/products/ETK-ETEKR.html
You might be able to find it a bit cheaper somewhere else though.

[FurtherThanTesla]

Ive seen similar Perm Mag DC motors on ebay for upper 200's

[BIGHAIRYDUDE]

you know you have the front fork backwards but overall nice

[sovereign]

The fork is actually the correct way, or else the brakes or bike wouldn't work.