HPI Racing - Nitro RS4 Racer 2 Tire Tips

Tire Tips

The new 24mm tires are a good compromise between the weight advantage of Super Narrow tires and the traction of Narrow tires. HPI offers them in different temperature-rated compounds for cool temperatures (use our 23R tires) and hot temperatures (use the 33R tires). Use the 23R tires in the mornings, and 33R tires in the afternoons.

Super Radials work best when the track is very dirty or on a completely unprepared street or parking lot. The directional treads kick out dirt and small rocks. This is the tire 'street bashers' will use the most.

The X-Pattern Radials are best on semi-prepared tracks, that is, lots that are a little dusty or dirty but not very clean, and maybe blown off but not sprayed with traction additives.

Trying using belted slicks on tracks that have been fully prepared (swept or blown off and sprayed with sugar water, VHT or soda), or permanent R/C tracks.

For more steering, try using belted rear tires and non-belted fronts, while staying with the same tread design. The belted tires are slightly harder than non-belted because of the nylon belt inside each one, and the softer tire in front will give more steering response. There are many ways to gain more steering, mixing tires like this is just one way.

Belted tires wear more evenly than non-belted tires, and provide more grip through the turns because the sidewalls flex a little bit less and have less of a "squirm factor" than the non-belted tires. Non-belted tires will flex more and have a less exact feel than than belted tires.

If the track is warm and the sun is out, most racers use slicks if the track is blown off sufficiently. The tires will warm while running and hook up better if the surface of the track is hot. Asphalt can reach 220 degrees Fahrenheit in most locations at the peak of summer, and the rubber in the tires will soften considerably, improving the grip of your car.

Super narrow tires, with their smaller contact patch, are a good companion to small, tight tracks. This is because they respond quicker to turning input from the driver. The reason for this is twofold: the super narrow tires have less rotating mass than a standard width tire and the weight of the car is concentrated on the smaller contact patch given by the super narrow tires. So, while you have less weight overall on the car, the average weight per given unit of area in the contact patch is increased. This higher concentration of the car's weight on the four contact patches of the car results in better turning response, making the car handle better for twisty tracks.

Super narrow tires also allow you to accelerate to top speed quicker and slow down faster, because there is less rotating weight for the motor to move. Lowering the weight of the car is nice, but a lower rotating weight is three times as good.

Standard width tires are used by most racers on medium to large tracks, because of the better acceleration afforded by the larger contact patches as compared to super narrow tires.

For a good commentary on touring car tires, check out this site: http://ourworld.compuserve.com/homepages/Avitaliti/techrepo.htm. Anthony Vitaliti has good suggestions for what to use, and when.