Cars and trucks have different tire profiles and will thus have different risks of damage when driving onto a curb. It is also important to establish whether parking on a curb is legal in your country or city. In most parts of the world, it is illegal to park on the curb.
Low-profile tires are prone to pinching the sidewall between the hard edge of the curb and the car’s rim, resulting in damage. Tires with a large sidewall height, such as off-road tires, are designed for climbing up sharp edges such as curbstones without any damage.
Tire size descriptions are a complicated and sometimes confusing tire size designation that industry experts understand but confuse most consumers. The tire size designation will indicate whether you have a low profile tire or a high profile tire on your vehicle. Driving into a curb at high speed will damage most tires beyond further use and also cause damage to the rims of the vehicle. Let me try to demystify the matter for you.
Will Driving Onto A Curb Damage My Tires
The sidewall of your tires will display the tire size designation in a format as follows:
Example: 225 / 45 R17
The first number, 225, is the width of the tire measured in millimeters. The second number, 45, is the tire profile ratio or aspect ratio. The R means that the tire has a radial construction and is common for all modern car or truck tires. The final number means that the diameter of the wheel rim is 17 inches.
If your tire aspect ratio is low and you drive into or onto a curbstone at speed, the sidewall will be pinched between the metal rim and the edge of the curbstone. Your speed should be slow as possible to avoid tire damage.
The tire size designation is a combination of metric and imperial dimensions mixed in with a ratio and an alphabetic descriptor. No wonder it isn’t very clear!
In our example, the tire width is 225 millimeters, and the sidewall height to tire width ratio is 45, implying that the sidewall height is 45% of 225 millimeters. The calculated height of the sidewall is 101.25 millimeters.
Low-profile tires are an aspect ratio smaller than 50. The tire sidewall is less than half the size of the tire width. Passenger cars and high-performance cars are typically fitted with lowed profile tires as they provide better stability.
High-profile tires are typical on trucks and off-road vehicles. The compression of the tire sidewall provides additional load carrying capacity and shock dampening. Tires are designed to allow the sidewall to deform when the tire meets an object, as happens when a tire drives into a curbstone. The tire sidewall will compress but not to the extent that the rubber of the sidewall is damaged.
The speed at which the tire runs into the curbstone must be low. The off-road adage is “As slow as possible and as fast as necessary.” Climbing rocks and boulders are well within the design capability of off-road tires. Off-road tires have aspect ratios of 60 or higher, allowing for a much large sidewall height.
Why Are My Tires Damaged By Driving Onto A Curb?
Parking on a curb may be required in special circumstances. It would help if you first established whether parking on a curb is legal or not. San Francisco does not allow people to park on a curb but recommends that drivers rotate their front tires to touch the curb when parking on a steep road.
If the brakes fail or the car is hit from behind by another vehicle, the car will not run into the street but be pushed onto the curb. In such situations, it is beneficial to follow such guidelines for safety reasons.
The low-profile tires of passenger cars or crossovers are not designed for climbing up curbs. The sidewall is too low and cannot compress enough to avoid being damaged between the wheel rim and the curb’s edge.
The aspect ratio on trucks and off-road vehicles is well above 50 and provides the tire with the ability to deform when slowly driven into a curb. The tire sidewall is tall enough to prevent being pinched by the rim and the curb edge.
Driving onto curbs is not recommended, and the resultant damage may be to the tire and the metal rim, resulting in considerable repair costs. Driveway ramps from the road onto driveways are at low angles and will not result in tire damage. Driveway ramps should be used to avoid tire damage.
Will The Tire Damage Be Visible After Driving Into A Curb?
Driving onto a curbstone intentionally or by accident may not always manifest in visible damage to the tire. The wheel’s rim may show signs of damage, but the tire still looks fine and is not losing pressure. Don’t be fooled. The tire is damaged.
The rubber surrounds a tire carcass made of steel and fiber. A tire inflated to 20 psi hitting a curbstone at speed will absorb most of the shock and deformation in the pressurized air between the tire and the metal rim. If the sidewall height is insufficient to deform enough to avoid damage to the carcass, the tire may be critically damaged.
The damage is not always obvious after a collision with a curbstone. You should have the tire inspected by a professional fitment center to establish that it is still safe to use. The condition of front-wheel tires is the most critical to the safe operation of a vehicle. If in doubt, replace the front tire with a new tire or rotate with the rear tires.
Conclusion
Parking on a curb may be detrimental to your finances as this practice is illegal in most cities globally and second only to potholes in causing tire damage. Off-road driving abilities do not allow you to park your vehicle on the curb when in the city. Just because you can park on the curb does not mean you should.
Potholes and curbstones are the leading contributors to premature tire replacement. Driving into curbs can also result in invisible damage, which may lead to the catastrophic failure of your front tires at high speed, with tragic consequences.
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