Tyres are one of the most abused components of any vehicle. They have to deal with bad roads, debris and sometimes, enthusiastic drivers. Keeping this in mind, the tyre manufacturers have started designing tyres that can protect themselves from these harsh operating conditions.
Most of the times, the measures consist of thicker rubber moulded at key areas like the tyre sidewall. Most commonly, the damage to the tyre is caused by tyre sidewall scuffing or making an impact with the curbs. Extra rubber provided on the sidewall helps to reduce the damage and prevent the internal structure of the tyre from getting damaged.
In spite of knowing how important these protected areas are for the tyre, sometimes manufacturers choose not to feature them on most of the standards and mass-produced tyres. This is because these standard tyres are often mounted on steel wheels that utilises hubcaps to enhance the appearance. The tyre protectors might interfere with the proper fitment of some hubcaps. So, the manufacturer choose not to feature them.
Although different tyres incorporate several designs, most of the tyres feature raised rib that runs along the bead area that also envelops the edge of the rim. Another common design is the thicker rubber rib at the maximum section width (the widest area of the tyre measured from the tyre sidewall).
Most of the low-profile tyres feature the raised rib running along the bead area. This is because low profile tyres are more susceptible to sidewall damage. Moreover, it protects the alloy wheels too. Generally, low-profile tyres are mounted on alloy wheels therefore, fitment of hubcap is not a problem.
Off-road or all-terrain tyres, on the other hand, use rubber rib at the maximum section width. Off-road vehicles have to tackle a lot of bad patches, debris or other random obstacles. Keeping this in mind, it is important to prevent the sidewall from getting damaged. Protecting the rim is not an issue for them as the tyres are mostly high-profile tyres mounted on steel wheels. The design of these sidewall protectors might differ from each other but their basic purpose is to sacrifice themselves to protect the integrity of tyres.