Kids' bikes with 20-inch wheels are abundant at the dump and yard sales, especially the cheap steel frame units. These bikes not only take a beating, but they are outgrown in a year or two, so you will probably find a lot of them at your favorite scrap yard or city dump. These frames are easy to chop, and 20-inch bikes make great choppers, but unless you are only 4 1/2 feet tall, there won't be much leg room on one of these bikes.

The problem of size is compounded even more if the head tube angle is taken back to add more rake, as this pushes the handlebars even closer to the seat. At this point, your only option is to move the seat higher or farther back, creating either a goofy looking chop, or a flying death trap that pulls uncontrollable wheelies on so much as a sneeze.

To get a little more leg room on a chopper made from kid's 20-inch frame, two frames will be joined together in order to move the bottom bracket further up. The head tube will also be pushed forward, allowing for a nice long set of forks to be installed without creating a super tall wheelie machine.

More cool projects can be found at: http://www.chopzone.com and

Step 1: Find a Donor Bike

The sacrificial lamb is a typical steel girl's frame 5-speed bike (Photo 1), fresh from the garbage heap at the local dump. For this project, you will need two 20 inch frames, and the components to make one complete bicycle. Depending on how you join the frames, the condition of the front half of one frame and the rear half of the other may not be important, as you will soon see.
<p>How do you take off the fork of a bike?</p>
Cool project! good work.<br>You dont want wide wheels ?
du u arc or mig weld? oops i forgot, or tig?
&nbsp;That's pretty tight and I know a thing or two about bikes considering I race BMX. Good job with this one!
&nbsp;brilliant... a fine piece of engineering
sick liking the dubble sproket
That's seriously cool. If I had a bike like that I'd ride it all the time (walking is for suckers).
It doesn't take long to build this. Give it a try!
I'm thinking of something similar for a trike cause I'm tired of falling over with a standard 2-wheel with my box full of stuff. But I want it to look cool. Either that, or I'll make the Trike off-roadable.
ok my parents still make me wear a helmet and its one of the big fat ones does anyone have any ideas for one that looks halfway decent and still works?
Go to your local bike shop and look for one. I have one that's not too bad, and yet still works.
I'm 32 and wear a helmet. Mostly because a lot of people who get hit by cars or fall off when biking suffer crippling braindamage as a result. But get a cooler helmet.
It's good to wear a helmet...especially if you wipe out often, but that doesn't mean I wear one. Anyway, if it's one of those big skater helmets, you could do a custom paint job to match your bike, I'm sure any reasonable parent would accept your argument. Just sand down the existing paint (not all the way, just so it's rough)then spray paint a base layer, and paint whateever you want on top.
nice chop..so nice i made one for myself..but i used 24 inch frames..nd changed some parts...
Could this bike be made bigger by using larger frames?
TOP CHOP,....very artistic,...love the ghost sprocket.
i really like how clean your bikes are. They appear to be made from a factory. i'm working on a twelve footlong chopper right know. all i have to do is paint it. keep up the good work.
Thanks! Join our Support Forum and send us pics of your completed chopper. We'd like to include it in our Builders Gallery. ATOMICZOMBIE.COM
sickkk im doin that to all my bikes in my garage
That looks deliciously dangerous.
cool thanks
would it be possible for a 13 year old to make this?
Depends. I know I could, but I don't know about the other 99% of kids in my school... (Then again, if you go here, then you can't be all bad :-) )
Absolutely! Basic welding is required, but if you know someone who can help you with that, you can easily build this in a weekend.
We use only a basic AC welder and a small angle grinder & drill. We don't recommend brazing at all for this type of work.
What type of welder are you using? I am looking at this for a winter project, but want to buy the right components... I'm torn between oxy-acetylene, arc, wire-fed... Don't know which one would be best for scrap projects like this...
Whoa! Cool stuff. Make sure you send us pics of your completed Hammerhead.
Aha! You have solved my goofy looky wheelie popping death machine problem.<br/><a rel="nofollow" href="http://static.flickr.com/60/162009890_726f28e588.jpg">http://static.flickr.com/60/162009890_726f28e588.jpg</a><br/>I've been thinking of ways to stretch this and make it more ridable. I was planning on extending the stays, but some variation of the above will work much better. <br/><br/>Your book was what got me started on hacking bikes. I'm currently saving up parts to turn this: <a rel="nofollow" href="http://static.flickr.com/65/169664786_385a81144c.jpg">http://static.flickr.com/65/169664786_385a81144c.jpg</a> into a hammerhead.<br/><br/>You rock!<br/>
Another cool project from you guys. Just got your book a couple weeks ago and totally dig it. Highly recommended.
Thanks, fungus! Have you joined our online forum yet? It's a great way to connect with other builders, share ideas, ask questions, etc. Also, don't forget to send pics of your completed bike projects for the Builder's Gallery. Hope to chat with you there. Cool stencils, btw.
Nice! Do you flickr? This bike would be perfect for the Orange Bikes photo pool:<br/><a rel="nofollow" href="http://flickr.com/groups/orangebicycles/">http://flickr.com/groups/orangebicycles/</a><br/>
Thanks for the link. Just uploaded some photos of this chop as well as an electric mini bike called Sparky that we just built.
another awesome build... I really love that extra chainring in there :P
Thanks! I'm just getting into hydroponics, so your projects are going to be a big help. Thanks for sharing.
Thanks guys! It wasn't easy finding a banana seat, though. Just lucked out at the dump one day.
Wow, I want one! Thats really cool!!

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More by KoolKat:Bike Hacking 101 - How To Perform a Bicycle Autopsy Build the SpinScooter Making Trike and Quadcycle Hub Flanges Without a Lathe 
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