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I remember always seeing an ad (in bmx plus?) for mail in instructions of how to buy the parts and put together a motorized bicycle / scooter for under 100 dollars. Did anyone ever actually get these plans or know where some are?

Also, does anyone have their own plans?
 

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I have seen a guy riding an electric he made out of an old mini-bike frame. It had a car battery sitting in the tray where the 5 hp engine would go
 

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Check out this vid:

[ame=http://www.youtube.com/watch?v=JhM81jVx6JM]YouTube - how to build a weedeater motorized bicycle[/ame]
 

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Thats really a good video he made with all the talk about lathes and milling machines etc....

Things have changed a bit however in the MB world. Complete kits are now available starting at about $109.00 for a small 2 stroke kit and up to about $650.00 for the more advanced, higher quality 4 stroke kits. Both versions are easilly bolted on to cruiser style bikes and some Mt. bikes as well. Its all alot easier than the video leads you to believe.Installation times vary bike to bike but a minimum of 4-5 hrs up to about a weekend for a novice. Enjoy the ride....
 

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the video is good as the guy explains the gearing and it easy to understand.

If you have access to good junk sweet:thumbsup:
 

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thats nothing check this out
[ame=http://www.youtube.com/watch?v=g_iviUNmjeQ]Motorized Bicycle with Jackshaft Kit - YouTube[/ame]
 

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I have one of the china kit bikes, and one of the friction drive kits with a japanese auger motor. I'd rather ride the weeder bike any day. The china kits are a hassle, heavy, and end up costing a bunch by the time you get the bugs worked out and get the upgrade cog, fuel shutoff, chain etc that the kit lacked.

bicycle engine kit, bike engine, bicycle engine, bicycle motor

$150 shipped for the dax drive, $80-200 for engines (gave $90 for mine shipped)
 

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And that engine would make it illegal on the roads in Texas with a gas engine without tag, registration and license. Electrics are a little more lax, but there are places you can not ride an electric that you can ride a regular bike.
 

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Whether they stop you or not is another matter, but if you have an internal combustion engine on it, its no longer a bike in Texas regardless of the size of engine. Electric bikes have some limitations but they can be legal.
 

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Give up already. I've been stopped before (for speeding lol). I got a warning. It's not illegal. Its a motor assisted bicycle, not a moped, not a scooter, and not a motorcycle. I don't know why you want motor bicycles to be illegal, but good riddance to you!
 

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But did you read the code? I have and really don't care what you ride or if you got a ticket or not. I did and I know what it said. Others can read for themselves and decide for themselves. Just because you got stopped and didn't get anything but a warning, is not making it legal
 

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Yeah, it is about mopeds and electric bicycles, not about motor assisted bicycles. Just because you misread it, doesn't make it illegal. I think you just are sour and hate motor bicycles, so you want to tell people they are illegal to discourage newbs.
 

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No I didn't miss read the code. The moped definition fit. Unless there were a specific authorization to allow motor assisted bikes, just as they allowed electric bikes with restrictions on wattage, some restrictions on where you could ride and top speed, then there is no such thing as a motor assisted bike. Just because someone sells it and tells you its legal, or you get pulled over and the cop doesn't give you a ticket doesn't make it legal. Everyone that gets on one of those things should check it out for themselves and just because they find someone on the internet that tells them its ok, well gee there is never anyone that is wrong on the net now is there. They may not get a cop that doesn't want to give a warning, and they shouldn't get a big fine without checking it out for themselves first. IF they decide to go ahead, good luck its not my business.

It might surprise you that actually considered getting one registered not that long ago for a number of reasons. I also decided it against it for very practical reasons. For those that care here they are.

First putting a motor on a bike stresses it in ways the bikes designer never intended. Most bikes when built designers would be expecting the top speed to be in the 20 to 25 mph range, and for the most part that would be a constant. Old steel frames might take higher stresses, but they also flex. Over time the bending back and forth would weaken any frame and at some point that much bending will cause it fail. Bend steel back and forth long enough and it will break. A lower speeds with lower vibration levels, that likely isn't an issue. Run the same frame at 30 to 40 for hours on end and the stresses are vastly different. The added weight and speed puts higher stresses on bike tires for which they were not designed to endure. Extra weight and speed would generate added heat and in 110 degrees added heat is the last thing a tire that really wasn't expected to be going that fast for an extended time needs. A scooter or moped frame and tires were, but not a beat up old steel bike. Aluminum might be lighter but my gut would tell me it would also be more prone to cracking.

Next is the fact that the seat and chain stays as well as the forks would be taking a real beating. IIRC from a science class if you double the speed, you don't double the force of the impact. That goes up 4 times with a doubling of the speed (and if any of the engineering types on this find this in error correct me) Regardless road debris, potholes and any other bump you hit on the road is going to be hitting much harder on a frame that has no suspension or a suspension that wasn't designed for the use. That could lead over time to failure of a fork or one of the chain or seat stays in the rear. IF you go down its at a much higher speed.

Then there is the stress on the frame where you mount the engine. It wasn't intended to handle the vibration of a fairly high level of rpm for the speed involved. No matter how that engine is secured, running it will cause vibration. Vibration over time more than likely will cause cracks. Thing is that crack may be under where the engine is mounted and totally invisible unless you pull the engine, that is until it fails with you doing 40.

Given all that, I decided the risk wasn't worth the reward. If I want a motor, I'll buy an ebike or a scooter, both of which are being used in the manner in which they were designed. That is why my decision was made, but if some one feels different good luck and be careful. If you can find a section in the code that describes a motor assisted bike and how it can be legal without a license, I'll be ready to stand corrected. Yet what is to stop someone from mounting a small block 350ci V8 on a bike, leaving the pedals on and calling it a motor assisted bike? Why not just put pedals on a sport bike and call it a motorized assisted bike. The definition of a moped fit, and I found no other code giving this set up and exception. You said yourself you were speeding, and the restriction on an ebike is to not be able to exceed 20 mph on level ground without pedaling. Think they would allow higher than that just because it went from an electric to an internal combustion engine?

No I really don't care what you do. Its your backside that will deal with it. What I do want the newbes to do is to think good and hard first. Gray hair sometimes does have its advantages.
 
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