Tech How-To
Many dirt riders groan at the thought of an afternoon burned changing a flat tire in the garage. But at least that misery is consigned to an area with shade, tools and refreshment easily at hand. What do you do when you get a flat on the trail or at the track? Do you let it ruin your ride? Or do you throw that bad boy in the dirt, wrestle in a new tube and fix that tire and your day of riding? You fix it and ride, duh! Fortunately (for you), Karel has more experience changing tires than most riders, with some 25-tire days, but Jimmy makes him look like a novice. On an off-road test one rider had a flat, and we had a pro photographer to document the process. Then we sacrificed an old wheel, and cut it in half to better illustrate what's happening when you change a tire.
 01 Before you get carried...  01 Before you get carried away, take an inventory of your tools and flat repair supplies to make sure you can complete the job in the field. It is a good idea to use your fanny pack to change tires at home, so you know you have everything you need. |  02 Start by removing the...  02 Start by removing the rear wheel. This is another reason you need to do tire changes at home using your fanny pack tool set. Ryan Orr has just realized that this WR axle was not tightened with a six-inch crescent wrench. |  03 With the axle nut off,...  03 With the axle nut off, turn off the fuel and lay the bike down so the axle head is facing up. Pull out the axle, and set it where it won't get dirty. Jimmy placed the other hardware on his tool roll to keep track of them and keep them clean. |
 04 Get the chain off the...  04 Get the chain off the sprocket, and pull the wheel straight back out of the swingarm. On most bikes the wheel spacers are identical from side to side, but keep track of them. You don't want to lose them or mix them up. |  05 Look for a flat, fairly...  05 Look for a flat, fairly firm spot to work. Most riders include a shop towel in their packs; use that under the sprocket to keep dirt out of the axle's hole. Loosen the rim lock and remove the valve core from the tube at this time. |  06 Jimmy shows the most effective...  06 Jimmy shows the most effective way to use your boots to break the bead on a tire. The longer the tire has been on the rim, the harder it will be to break the bead loose. Using a heel close to the rim maximizes your efforts. |
 07 The rim has a dip or well...  07 The rim has a dip or well in the center to allow you to change tires. The bead of the tire must be down in the well of the rim on one side, so you can work the tire over the rim on the other side. These beads are pushed in but are not down in the well. |  08 With the bead of the tire...  08 With the bead of the tire pushed into the well opposite the side you're working on, the tire will easily work over the edge of the rim on the other side of the wheel. Kneeling on the tire with the wheel on the ground will naturally hold the bead down. If you need to fight with the tire, the opposing bead is not in the well. |  09 Start by inserting two...  09 Start by inserting two tire irons under the bead. Pull the first one over and tuck the end under the disc if the iron is long enough. If not, kneel on one, then work your way around the first side of the tire taking small bites with the second tire iron. |