How to Mount a Tire

with Justin Stefani
Technical Director for Compkart

This is one of the most frequently asked questions not only to Kart360, but also in general. At first glance it is thought to be all about brute strength or big hands, yet this couldn’t be further from the truth. Justin Stefani from COMPKART walks us through his preferred technique on mounting karting tires.

Wheel Maintenance and Preparation

Figure 1

Whether you have dismounted an old set of tires and are mounting a new set or you are mounting tires on a brand new set of rims you should always inspect the rim itself, the bead locks, the valve stem, and the o-rings that go onto the bead locks (figure 1). Look for any cracks or abnormal wear and make sure you have the correct amount of bead locks and o-rings. Each wheel will take three of each.

Figure 2

Next you will want to insert the bead locks with the o-rings attached into the wheel. They will simply be hand screwed in, but it is important to make sure they do no protrude into the inside of the wheel (figure 2). This will damage the tire when setting the bead with air.

Mounting Process

Figure 3

As stated above this is more about technique than strength. We recommend using a small amount of soap and water solution on both the inside and outside bead of the tire. Next place the inside part of the rim at a 35-45 degree angle and press the rim into the tire (figure 3).

Figure 4

Flip the tire and wheel over to mount the other half by pressing in one side of the tire and pulling the rim up to create another 35-45 degree angle. Place the rim flat onto the ground and press on one side of the rim to finish the mounting process (figure 4). Depending on the stiffness of the sidewall you may have to work your way counter clockwise if you are right handed until it is full mounted. Lastly work the tire so that the bead sits flush around the rim. This will help with the popping of the bead.

Inflation and Popping Bead

The next step is to pop the bead. You may want to spray a little more soap and water solution around the bead to allow for easier inflation. As you inflate you will hear two pops, one being the inside and the other the outside bead. Once both beads have popped you will want to remove one of the bead locks to allow for all of the air to escape, which protects the tire from over inflation. If you do not do this you run the risk of stretching the tire and possibly causing a difference in tire circumference side to side.

Finishing Touches

Figure 5

Once all of the air is removed from the tire you can screw in all of the bead locks. It is important to not over tighten the bead locks as this could damage them. Once they are tight inflate all four tires to the same pressure (we recommend 15 psi or 1 bar). We will want to make sure there are no air leaks in the tire. We can take water and pour a small amount over each bead lock and the valve stem. If you see any bubbling it means you have an air leak (figure 5) and most likely they will just need a little extra tightening. Once you have ensured there are no leaks the tires are ready to be mounted onto your chassis.