by betty.k

These are the tires I’ve been using, but use whatever you want. Mount the tires on some wheels & axles to make it easier to hold. The 2 most important tools for this job are:

A new, razor sharp scalpel or hobby knife, small is good. Ideally you want a curved and a straight blade, but either will do.

PATIENCE!! Be prepared to ruin a few tires before you get this right. Start on some crappy ones.

Notice how there’s 2 halves to the tire. Divide each half into thirds. Start the first cut 2/3 of the way into the outside half. Cut around the diameter of the tire, but no deeper than the actual chevron (chevrons = the knobby bits).

Start 1/3 of the way in this time and one by one, cut at about a 45 degree angle towards the first cut so the 2 cuts meet up at the base of the chevron, no deeper. So you’re removing the middle third. You can see one of the middle bits on the scalpel blade.

Repeat the procedure for the inner half of the tire. This is a finished rear tire. Angle the cuts whichever way you want, I find that this design with 4 sharp edges facing outwards provides the best cornering traction.

For the front tires, do the same with the outer half. Then make a cut in the middle of the tire, around the diameter of the wheel. Again, just cut as deep as the chevrons, this cut is a guide for the next step.

This is where the straight edged blade comes in. hold the wheels sideways, and cut straight down into the inner side of the tire to the halfway point you marked, NO FURTHER! Then cut sideways along the halfway point and meet up with the vertical cut. Go around the whole tire like this, a bit at a time until it’s round all the way. I do this to prevent the front tires from rubbing on the chassis when turning.

Once you’ve evened them up and mounted them on my custom wheels, you’ll notice that they stick out a little on the inside compared to the ones on the car. I just trim this flush with the wheel, mainly for aesthetics, but it doesn’t need to be there and may rub on the chassis.

…like this!

As you can see, the tire would have rubbed on the chassis if it were not cut down.

The finished products! These tires excel on concrete, but are suitable for most outdoor and off-road applications.

Next: Off-Road Bits – Part 9: Ramps

This entry was posted on Friday, May 28th, 2004 at 4:06 pm and is filed under Fabrication, Micro. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.