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Old 02-08-2013, 08:01 AM
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Crazy Horse Crazy Horse is offline
Join Date: Feb 2009
Location: USA
Posts: 1,150
Thumbs up Re: Crazyhorse's Custom Motorized Bicycle Builder build a shop with Harbor Freight To

Steps to Build a Custom Bicycle Frame

Before you start on your endeavor of making a custom bicycle frame, you must consider the fact that you need to be adept at tasks such as cutting the metal and welding the different parts together. If you are not skilled at tasks such as these, then you need to take the help of someone who is skilled enough to help you. ie your local welding shop Here you can with patience learn to build a your own bicycle frame as it is the easiest to build. In order to build your very own custom bicycle frame at home, there's a small list of things that you must have.

Materials And Tools Required

Frame jig ( See CulverCityClassics Thread Inexpensive Frame Jig Thread )
Tube bender
Long steel tubes (1" to 1.25" diameter and 10 to 16 gauge thickness)
Steel tubes diameter is whatever your preference is
Measuring tape
A saw
A angle grinder
Nuts and bolts
Engine plates
Steering neck
Safety gear to protect your hands and eyes

Now that you know what are the things you need, let's move on to the procedure of making a custom bicycle frame. Follow the steps suggested / given below.

Step 1: Creating the Design
The first step is to draw the design you want, on a piece of paper. Use your imagination and make a rough sketch and mention the specifications on the drawing. You need to specify things such as the rake (angle of the steering head aka headtube), stretch, strength, trail, wheel base(distance between the center of the wheels), etc. You can even download technical blueprints from the Web to serve your purpose. Once you have the sketch ready, you can put it up before you for reference. You can go to your nearest Kinkos copy center and have them print you full sized drawings of your design.

Step 2: Taking Measurements
The next step is to measure the length of the various parts and mark them on the steel tube. Use the protractor to measure the rake angle and the angle of the neck. Normally the rake angle is close to 40 degrees (measured from a vertical line drawn through the center of the neck). As for the axle heights, it depends on the wheels you use. Let's consider you're using 21" front wheel and 18" rear wheels. In that case, the front and rear axle heights will be 10.5" and 9" respectively. Now, is a good time to place the engine on the frame jig to locate the positions of the engine mounts. Remember to hold it a little above the jig to account for the thickness of the frame tube. You can try aligning the neck to decide the angle of the downtubes. Let's consider the angle of the downtubes to be 70 degrees.

Step 2: Cutting the Parts
Now that you have all the measurements ready with you, the next step is to cut the parts using the an angle grinder or saw. Remember to cut the pieces a few inches longer than the desired length. This is to allow for the pieces to be cut short if need be, in case of errors during welding. You need to cut pieces to form the rear triangle, dropouts / axle, center brace, headtube / steering yolk, the downtubes, the top tubes and the bottom tubes.

Step 3: Welding the Parts
Before you begin welding the parts using a welding gun, make it a point to wear protective gear. Wear goggles to protect your eyes and gloves to protect your hands from the sparks during welding. Place the pieces along the jig and start welding. First of all, I start lower or bottom tube of the frame, and work my way up to the top tube. After you're done with the welding, you can begin assembly of the bike fix. This completes the basic structure of your custom bicycle frame.

Step 4: Adding the Finishing Touches
Once you have finished with the basic structure, use the sandpaper to file the joints to make them appear smooth. If you know how to paint a bicycle, paint it in a color of your choice and baa-bam! Your attractive brand new bike is ready for a ride!

Thus, you see that building a custom bicycle frame is not as difficult as it seems. If you are not skilled enough at tasks such as welding and metal-cutting, you can still have a customized bicycle of your own. All you need to do is to get an old bike and redesign it to give it a look of your choice! This may appear easier and takes less time. So, go ahead and give your bike a new look or better still, make a new one to suit your tastes!

Here's CulverCityClassics thread cheap bicycle frame jig

P.S. Builders check this thread for in depth info for Horizontal 4-stroke Honda crf50 Pitbike / Dirtbike / Atv engines:
These engines work best used for motorizing the Stretch Cruisers & Chopper builds.
P.S. Builders check this thread for in depth info for Horizontal 4-stroke Honda crf50 Pitbike / Dirtbike / Atv engines:

These engines work best used for motorizing the Stretch Cruisers & Chopper builds.

Last edited by Crazy Horse; 02-09-2013 at 02:57 PM. Reason: typos
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