Is it possible to diy my own electric bike?

[Legolessed]

I bike a lot with my friends and I thought it would be a fun project to attach a motor somehow to the bike and have an electric bike. I don't want to make any permanent mods to my bike and k want to spend very little on this. Is it possible?

[Simon771]

Anything is possible if you put your brains and wallet to it.

[Legolessed]

15 minutes ago, Simon771 said:

Anything is possible if you put your brains and wallet to it.

What motor would work? And could I just mount a motor on top of the tire, have one wire from. The motor leading to a battery and the second one leading to a switch?

[ARikozuM]

Nothing is true, everything is permitted.

 

That said, you can find tutorials online.

 

http://www.wikihow.com/Build-an-Inexpensive-Electric-Bicycle

[Simon771]

1 hour ago, Legolessed said:

What motor would work? And could I just mount a motor on top of the tire, have one wire from. The motor leading to a battery and the second one leading to a switch?

I have no idea about bikes, and motors and how that should work.

Also not sure if there are a lot of people who knows something about that on this forum.

[Hackentosher]

@CUDA_CoresIs doing it. 

[corrado33]

Sorry, the answer to this is no. My other hobby is bikes. You will not be able to do this without A. spending a decent amount of money or B. making permanent mods to your bike.

 

Generally people that do it cheap make the motor forever connected to the tire. That means the bike is useless as a pedal bike anymore because you also have to use energy to turn the motor. 

 

So you put the motor on a hinge. That's more difficult, it's more expensive. 

 

So you think about putting a centrifugal clutch on the motor (like a weedwacker). That's more expensive, and those things require very high RPM to work, so you'd have to make the motor work through some sort of gearing. Again, more money. 

 

There are right ways to do this, and none of them are cheap. You will not be able to do it without significant mechanical experience or a significant amount of money. The batteries for electric bikes are hundreds of dollars. I know, I've looked. 

 

I have thought very hard about building a motorized bike. I'm telling you that I know bikes much better than you do (I work at a bike shop). It's not an easy process and I gave up on it because it would have taken too much time and energy. 

 

It may SEEM simple, but it is not, trust me. 

[straight_stewie]

10 hours ago, Legolessed said:

I bike a lot with my friends and I thought it would be a fun project to attach a motor somehow to the bike and have an electric bike. I don't want to make any permanent mods to my bike and k want to spend very little on this. Is it possible?

It's extremely possible. You could easily cheat and build it the same way that people build friction bikes. The best thing about this is that it proves @corrado33 wrong.

 

As an aside, making a friction bike is definitely not the correct way to add any engine to a bicycle, it's just a cheap and easy way.

[corrado33]

3 hours ago, straight_stewie said:

It's extremely possible. You could easily cheat and build it the same way that people build friction bikes. The best thing about this is that it proves @corrado33 wrong.

 

As an aside, making a friction bike is definitely not the correct way to add any engine to a bicycle, it's just a cheap and easy way.

Please, I would LOVE to see someone try. Please post it here. Seriously. I GUARANTEE YOU that no one here will ever make one that works reliably and easily. 

[Hackentosher]

2 hours ago, corrado33 said:

Please, I would LOVE to see someone try. Please post it here. Seriously. I GUARANTEE YOU that no one here will ever make one that works reliably and easily. 

@CUDA_Cores, care to chime in here? What about the Radpower bikes? Those guys started by building their own electric bikes in their garage then turned it into a successful business. I think you underestimate the wonders of determination, effort, and throwing enough money at a problem until it's fixed

 

[ARikozuM]

1 minute ago, Hackentosher said:

@CUDA_Cores, care to chime in here? What about the Radpower bikes? Those guys started by building their own electric bikes in their garage then turned it into a successful business. I think you underestimate the wonders of determination, effort, and throwing enough money at a problem until it's fixed

 

@CUDA_Cores has been banned after picking a fight with another user over AMD/Nvidia. /s

[Hackentosher]

12 minutes ago, ARikozuM said:

@CUDA_Cores has been banned after picking a fight with another user over AMD/Nvidia. /s

Sheeiit, another one bites the dust. 

 

@CUDA_Cores is in the process of building an ebike using 18650 cells and a hub motor instead of buying a car. Check his old status updates. 

[ARikozuM]

1 hour ago, Hackentosher said:

Sheeiit, another one bites the dust. 

 

@CUDA_Cores is in the process of building an ebike using 18650 cells and a hub motor instead of buying a car. Check his old status updates. 

I hope you noted the "/s" in my post. I'm just using @CUDA_Cores as an excuse to flood his feed with mentions. You know, for science.

[Hackentosher]

2 minutes ago, ARikozuM said:

I hope you noted the "/s" in my post. I'm just using @CUDA_Cores as an excuse to flood his feed with mentions. You know, for science.

I'm blind  I wouldn't be surprised if he was banned given recent bannings.

[straight_stewie]

5 hours ago, corrado33 said:

Please, I would LOVE to see someone try. Please post it here. Seriously. I GUARANTEE YOU that no one here will ever make one that works reliably and easily. 

The internet is full of friction bikes using weedwacker engines. I don't see doing an electric one would be too much different. Instead of mounting a fuel tank you mount a battery pack and instead of friction with the drive shaft of an internal combustion engine, it's friction with the drive shaft of an electric motor. 

I'm not saying that it's the right way to do it, or that it will have any quality or reliability. I'm simply saying that it's the cheapest way to do it.

[corrado33]

13 hours ago, straight_stewie said:

The internet is full of friction bikes using weedwacker engines. I don't see doing an electric one would be too much different. Instead of mounting a fuel tank you mount a battery pack and instead of friction with the drive shaft of an internal combustion engine, it's friction with the drive shaft of an electric motor. 

I'm not saying that it's the right way to do it, or that it will have any quality or reliability. I'm simply saying that it's the cheapest way to do it.

Ok fine, let's take your example. 

 

Cheap electric motors run at high RPMs. How do you plan on getting it to spin slow enough to match a reasonable speed on a bike? How do you plan on charging the MASSIVE battery pack you're going to need to run this thing for more than 5 minutes at a time? You realize how dangerous this is if you're using Li-Ion? Ok, so chalk up an "expensive charger" to the bill of materials.

 

Next question is this. There's no sort of freewheel or clutch on electric motors. So basically it's either 100% on, or 100% off, unless, of course, you buy a nice H bridge setup and send PWM to the motor. So what are you going to do there? Is your simple "on off switch" still going to work? You realize that if the motor had any purchase on the tire it'd just flip the bike over immediately correct? If it DIDN't have purchase on the tire it'd simply burn a hole in the tire from spinning against it. 

 

Just for the record, 500W motors (a typical bike motor wattage) are AT LEAST $100. Most of the time they're more up around $200. You can tack on another $50 for the controller itself. To run the bike for ONE HOUR, you'd need 5x7 18650 cells. That's at LEAST 35 cells. Assuming cheap chinese cells which are likely to break very shortly, that's at least $87.50. That's to run the bike for ONE HOUR. If you bought actual name brand batteries, it'd be 2-3 times as much. 

 

So, how do you charge such a massive battery? In all honesty, I have no freaking clue. There doesn't exist a stock charger large enough. So you'd have to make something yourself.

 

Still think it's an easy project? How do you plan on mounting the motor to the bike? The motor itself will be heavy. Do you still want to go with a friction drive? If not, how much are the gears going to be so that you can use a chain. I'll let you in on a secret, gears aren't cheap. You can probably chalk up another $50-$100 in gears alone. 

[ARikozuM]

You two do realize that it's entirely possible to add a throttle to a bicycle, right? 

 

Refer to my previous post for the Wikihow link that works very well on most bikes.

[corrado33]

1 hour ago, ARikozuM said:

You two do realize that it's entirely possible to add a throttle to a bicycle, right? 

 

Refer to my previous post for the Wikihow link that works very well on most bikes.

OP wants to spend "very little" on this.

 

It's not possible. Period.

[Shog]

Yeah this is definitely feasible. I think instead of asking which motor would work you should read an article or two on it and decide how far you might want to go. 

For $150 (prices have gone up since I last looked, you can buy a motor for $50 then rerun the chain and buy the parts of the kit separately) you can get a hub motor kit and then buy another $20-50 for batteries/knickknacks and be on your way. I guess it depended on what you meant by permanent, just pop the wheel off when you're done. 

Personally I have a job and a bike, I'll probably put in about $750 and build myself one that'll go 40+ mph for quite awhile  (Lithium iron phosphate batteries would be the majority of the cost) Buzz past those commuters in their puny cars. 

Feel free to ask me more questions if you want specific opinions or question answers. I think it's entirely reasonable with a budget to slap $150-200 down on some parts and build your bike. It'll probably take 10 minutes to swap out the tires and batteries if you set it up right and replace wheels at a forgiving pace. 

[ARikozuM]

1 hour ago, corrado33 said:

OP wants to spend "very little" on this.

 

It's not possible. Period.

I did this on an old Schwinn and it only came out to $120 with 2 batteries, some wires, and a master link.

[Hackentosher]

3 hours ago, corrado33 said:

Snip. 

Dude chill. This isn't rocket surgery, it's clearly possible. Also OP hasn't given a budget, the term cheap is relative. We don't know if the OP has $20 or $200 on this project. 

[corrado33]

4 hours ago, Hackentosher said:

Dude chill. This isn't rocket surgery, it's clearly possible. Also OP hasn't given a budget, the term cheap is relative. We don't know if the OP has $20 or $200 on this project. 

Absolutely possible yes, possible to make a cheap/reliable bike? No.

 

Cheap/Reliable/Easy to install

 

Pick 2. 

 

You have no idea how many "failed" motorized bikes I've seen come into my shop. The ones that work are the ones that buy a $200 ebay kit with a motorized hub. And those ones usually come in because the battery crapped out. 

[straight_stewie]

8 hours ago, corrado33 said:

-snip the angry "it's impossible" response-

You may work in a bike shop, but some of us are engineers. 
Besides that, I keep agreeing with you that it can't be done (e-bike) cheaply and still meet all three criteria. Yet you keep biting my head off. 

To be quite clear, you can cheaply do this problem with a cheap, low speed, low power motor (like you could get out of a used garage door opener or washing machine) and a car battery, some glue circuitry, and the right gearing. So please, tell me again how it's impossible. Obviously @Legolessed isn't trying to build anything like what's on this list. Perhaps, however, he would be ok with something that he could cheaply build himself, even if it's not as nice as a production bike would be (obviously, because that's exactly what he asked).

IMO, OP would be better suited by a normal, weedeater friction bike anyway:
 

 

[Cyborgsmith]

On 11/29/2016 at 10:36 PM, Legolessed said:

I bike a lot with my friends and I thought it would be a fun project to attach a motor somehow to the bike and have an electric bike. I don't want to make any permanent mods to my bike and k want to spend very little on this. Is it possible?

There are some DIY style kits that you can buy that work as an "addon" the problem is they tend to be load and seem gimmicky compared to the direct drive hub motors.