Thursday, March 15, 2012

How to build a phat ass chopper wheel - Part 1

Atomic Zombie's OverKill chopper


Let's face it, a chopper needs to have a wide rear wheel in order to stand out among the pack. In fact, the wider the better! I remember the days when a bicycle chopping involved hammering a cut off set of forks onto the ends of another set and then replacing the front wheel with a smaller diameter wheel.

Well, those days are history, and now a custom chop may involve a year of work and several hundred dollars of machined “bling” in the mix. Things changed about 10 years ago when department stores began mass producing these chopper bicycles with 4 inch wide tires, something that was not available before that time.

At first, I was thinking "cool, a new source of parts", but then I started seeing these cookie-cutter factory jobs all over the place, and they all looked alike. In fact, the only difference between these so-called "customs" was the color and the eight digit serial number. Seeing this sacred ground infected by the big box stores made me take drastic action, and I set out to make a chopper that would mock these department store bikes both in look and in cost. I wanted to blast the chopper proportions way out there and do it for only a few bucks, so I designed OverKill.

To spew insult at these 4 inch wide rear wheel departments store chops, I would have to go way overboard on the rear wheel, so I started looking at ways to fit a motorcycle wheel to a bicycle hub. After a few prototypes I realized that I was only a slight bit larger, having tires of 5 or 6 inches in width. I scraped the motorcycle wheel idea and went to the auto wrecker to scrounge up something bigger, much bigger.

After a bit of digging, I found an old steel rim with a 15 inch wide drag slick, and that formed the basis for the OverKill Chopper. After that, many other creative chops started popping up based on the OverKill plan, each with some amazing custom twist. Am I laying claim to inventing the car wheel chopper? No sir, but I would like to think I had a hand in putting these department store chops back in their rightful place - well behind the real custom.

So, let's have a look at how easy it is to whip up a phat rear wheel for a bicycle chopper. All you need is an old steel rim with a tire and some common bicycle parts. I didn't have room in this release to show the creation of the wide hub, so we will just start with the process of lacing the wheel, which is much easier than you might think.


Figure 1 - Getting ready to lace a car rim

At this point, we have the custom wide hub which is made from an old steel BMX hub and a set of 72 matching spokes. Why 72 spokes? Because the original hubs had 36 spokes and I drilled a second set of holes on each flange to double the number of spoke holes. This allows the creation of what is really 2 laced rims on each side of the car rim to offer both strength and a thick look to the finished wheel.

Spoke length is not important here, just use common spokes made for a 20 inch rim when you are lacing a 15 inch car rim, and they will fit. If you know something about lacing a bicycle wheel, forget it now because the technique used to lace a car rim is completely different and much more simplified.

Figure 2 - Adding the first two spokes

Start by handing the hub by two spokes as shown in Figure 2. These are both "inside spokes", meaning that you push them into the spoke holes on the hub towards the inside of the rim so that the round head is facing outwards. Spin the spoke nipple around two or three times to hold the spokes in place. Be careful when pushing the spokes around that you don't scratch the paint on your rim. The spokes are sharp at the ends and will easily mark up your new paint job if you are not careful, especially when getting the last few to bend into position.


Figure 3 - Keep adding more spokes into every second hole


Keep adding more spokes to the rim, but only in every second hole so each spoke pair has a blank hole between them. These spokes will all be inside spokes, so they are pushed into the holes towards the inside of the rim. You will need to add 36 of these spokes to the rim.

Only turn the spoke nipple a few times, and try to turn them all about the same amount.

Figure 4 - Turn the hub to remove the slack

Once you have one side completely laced with spokes, you will notice how loose they all are. Did we use spokes that are too long? Nope, this is all part of the plan, and if you give the hub a spin, you will see that the slack is picked up as the spokes begin to exit the hub at an angle. This can be seen in Figure 4, as I have one side laced and have the hub twisted to take up the slack in the spokes. Continue adding spokes to the other side of the rim in the same manner.

More in the February 27, 2012 newsletter  >>