Build a Moped
Mopeds are a fun and exciting alternative to more traditional transportation, but if you want to buy a moped at its current price, you might as well save up for a car. If you want to build your own moped, then you can just modify a mountain bike for electric power. It'll work just as well and will be only 1/4 the cost you would pay for a brand new moped, might be quicker too!
Steps
- Decide what is more important, power or speed, this is an important choice to make, and affects the rest of the project greatly
- Buy a cheap mountain bike, disk brakes are optional but HIGHLY dangerous as they will bend and cause you to donkey kick, or spark and ignite any flammable material.
- Go to an online electric scooter store, where they sell replacement parts and upgrades for commercially available models.
- Purchase a motor, it is easier if it comes with a pre-attached sprocket.
- Purchase a controller, it is a little pricey, but ABSOLUTELY ESSENTIAL, it makes sure that the right amount of power goes to the motor, manages speed, battery level indicators...etc.
- Purchase batteries, depending on what power your bike will be (24V, 36V, 72V) most people use lead acid batteries, but they are slow to charge and VERY HEAVY, a few people have used 2, 18 Volt batteries from cordless power tool sets with good results
- Purchase an electric throttle, you COULD be cheap and make your own using a potentiometer, but do yourself a favor and buy a real one.
- Purchase a fairly heavy-duty chain, and a 16" sprocket.
- Note that now comes the hard part, you have to attach your motor to the bike frame very solidly, welding is the strongest, but many have gotten away with using nuts and bolts, ideally, you should place the motor fairly close where the water-bottle holder would go, but below the seat would work too.
- Attach the 16" sprocket to the back wheel by removing one of the other, smaller sprockets, and putting the new, bigger, one in it's place.
- Link the little sprocket on the motor to the 16" sprocket on the back wheel using a chain, you will have to fool around with chain lengths to get it right, it should be tight, but not too tight.
- Mount the controller box to the bike, the best spot to attach it is on the inside-side of the horizontal support bar on the handle-bars.
- Mount the batteries, the only real spot with enough room is in a little container you'll have to mount behind the seat. This will enable easy access and keep them out of the way.
- Remember to know where to connect all the wires, read the instructions that came with the controller box, it is fairly straightforward system, "Batteries into this plug, motor into that one, throttle into this one"
- Treat yourself out to Lunch, because you did it! Now just charge the batteries, double check all of your connections and hardware mounting and go for a ride! Done right, and one should be able to cruise around with minimal or no pedaling at speeds of anywhere between {{safesubst:#invoke:convert|convert}}!
Tips
- You need a valid drivers license in most state to drive a moped, however a recent law was passed distinguishing mopeds from "electric bicycles", now gas-powered bikes are mopeds, and electric powered bicycles that run at under 750 watts are considered bicycles and they can be used anywhere and by anyone a normal bicycle can be.
- You need the strength of a mountain bikes frame, but replacing the rugged mountain wheels with lighter road wheels is a good idea.
- If a website only says the Voltage and Amps of a motor or controller, remember, you can find out the watts by simply multiplying the two. Example 20 amps x 36 volts= 720 watts. That's a good wattage.
- Pedaling a little when climbing hills is a good idea, it will help to keep the batteries alive.
- There's no point making this if it's going to be under 400 watts, it just won't be strong enough to be fun (or useful).
- Buy a strong motor, they come in every size from 75 watts to 2500, most states permit only a maximum of 750 watts (1HP). You are safe with an anywhere between a 500 and 700 watt model.
- Bring a few extra fully charged batteries, you'll be glad you did on long trips.
Warnings
- Expect to get pulled over a little bit at first by police, as long as you obey the law they won't give you any problems.
- Make sure mopeds are legal where you live!
- Mopeds are NOT allowed on highways!
- Put some battery powered lights on the moped, so you don't get run over at night.
- Always wear a helmet, some would go as far as to say even wear elbow and knee pads.
- Buy a controller that is rated to stand AT LEAST 75 watts more than the maximum rating of the motor, when you climb hills, the motor works a lot harder and if there isn't enough power supplied, the controller will start smoking.
Things You'll Need
- A little technical know-how
- A sturdy mountain bike
- A 400 watt or more motor
- A controller
- A few batteries
- An electric throttle
- A 16" sprocket and a chain
- Some various hardware
- A small basket for the batteries
- Optional: Road tires
- Alot of money
- A drivers license (most states)
Related Articles
- Be Cool on a Scooter/Moped
- Make Your Moped Faster and Run Better
- Make a Scooter/Moped/Motorcycle Accessory Bar
Sources and Citations
- Article written by Thayne the Brayne
