SAFETY

• Only trained people, using safety goggles and following the handbook instructions, should mount tyres.
• Do not try to mount a tyre on a damaged wheel, and do not exceed the maximum pressure shown on the sidewall of the tyre.
• Keep a safe distance from the wheel during the inflating process to avoid injury in case of explosion.
• After mounting the tyres, put a little soapy water around the rim to ensure there is no air leakage.
• Before the race, make sure there are no problems with the tyres (cuts, holes etc.). This is especially important at meetings when you use the same set of tyres for two or more races.

DISMOUNTING

To deflate the tyre it is recommended to remove the valve. You can also just press the valve and still leave some air in the tyre, but this will make the process more difficult and a little slower. Some wheels, especially those made from magnesium, have three screws to avoid the tyre spinning on the rim or 'jumping off' it. These screws are really necessary on tracks with extremely high-speed turns on in situatuions when a very low tyre pressure is the only way to go. In this case, before disassembling these kind of wheels, completely remove these screws to avoid damaging the tyre. When using a bead breaker (diagram 1) you must be careful to avoid applying too much pressure in just one section of the tyre sidewall, so as not to cause any damage to the tyre bead. The wheel should be taken off over the 'outside' edge of the wheel. With both sides of the tyre loose around the 'waist' of the wheel, fold the inside wall (diagram 2) and push in the lower inside part of the wheel (diagram 3). To finally take the wheel off the tyre (diagrams 4, 5) it may be necessary to brush the bead with a soap/water mixture.

MOUNTING

To mount the tyres, you just have to basically reverse the procedure for dismounting. The use of a mixture of saop/water on the bead is recommended (diagram 1). Even though you may feel tempted, never use grease or any other kind of mineral lubricants. The first thing you should do is check which side of the kart the tyre is going to be used, and make sure you are mounting it according to the rotation arrow on the sidewall. Once the outside wall is determined, the wheel inner face should be pushed through it (diagram 2). The next step is to put the wheel inner lip through the tyre's inside face. This si done by folding the inside tyre wall and pushing it into the 'waist' of the wheel (diagram 3). Next, lay the wheel with its inner face up, and push the tyre over the lip of the wheel (diagram 4). To inflate the tyre, remove teh valve for better air flow. The air pressure should not exceed 42-56psi (diagram 5). Care should be taken because of the danger of breaking the wheel when the tyre pops up against the bead. It is a good measure to place the wheel inside a sturdy container to avoid injuries in case of breakage. Some companies have specific products designed for this purpose. You should always use safety goggles during the process, and never under any circumstances try to mount a tyre on a damaged wheel. After mounting the tyre, put the valve back and bring the tyre to the right pressure according to the compound you are using and the track characteristics.

AIR PRESSURE

• Tracks with low grip require higher air pressure - start with 13-15psi (hot tyre).
• On the other hand, tracks with more rubber on the ground require lower air pressure - 10-13psi (hot tyre). This si common at meetings with many karts on the track.
• Weather changes affect chassis behaviour and air pressure adjustment may be necessary to maintain the same chassis balance.
• A softer compound requires lower air pressure than harder compounds.
• Take care fo your tyre pressure gauge. One or two PSI can affect the handling, so it is important to have a good quality gauge and to avoid dropiing it, to keep it accurate for a long time.

TYRE TEMPERATURE

A kart tyre works best when in the 85-95 degrees C range. Use a pyrometer to measure the temperature of the tyres during a test session. It is important to remember that chassis setup or changing driving style can help to avoid overheating the tyres, keeping them at their performance peak. Track conditions at each circuit also play a big role on tyre temperature variations.

BALANCING

Balancing the wheels is very important to achieve the best performance from your kart, with direct effect on handling, top speed, tyre wear and comfort.

The balancing of the front wheels can be done with the tyre and wheel assembled on the kart, while the rear ones need a support or one of the balancing tools available on the market.

The idea is to give teh tyre/wheel assembly a little spin and make sure it stops in random positions every time, without rocking back and forth. Add a self-adhesive balancing weight on the upper side of the wheel if it rests frequently with the same side downs or if it 'spins back' before coming to a stop.

'RUNNING IN' TYRES

The best way is to inflate them to the correct tyre pressures and complete 5 installation laps without braking hard or skidding the back tyres and drive through the corner and not slide through the corner.  In other words drive smoothly for 5 laps.

STORAGE

Deflate tyres after a race or practice to avoid deformation due to the effects that temperature increase has on the rubber. Many times the same set of tyres are used for two or more races in a race-weekend, and this procedure helps to keep a consistent kart behaviour.