Tyres and rims can get damaged by a curb or different objects.An abrasion in the sidewall may lead to the tyre ballooning and then bursting.Abrasion on the rim, on the other hand, may chip the paint and damage (dent) the rim's fringe.A rim with a damaged fringe is more susceptible to corrosion and can, in extreme situations, influence the overall balancing of the wheel.Moreover, a rim with a damaged fringe will lose its visual appeal, which is especially important in aluminium rims.How do manufacturers protect their products from this kind of damage?
Many of today’s tyres protect their sidewalls and rim fringes against such damage by using special shields called protective flanges (tyre rim protector systems).This helps reduce the damage done to the tyre and/or rim when the driver rubs the wheel against the curb when parking or turning.The protective flange is most often installed on passenger cars with a tyre profile of 55 or less, but there are some exceptions (depending on the manufacturer).Why profile 55 and less? Because such tyres, called low profile tyres, are most often installed on alu rims.Moreover, tyres above profile 55 are so "ballooned", that the fringe of an alu rim is easily hidden.But, as mentioned above, the relation of low profile tyres and the tyre rim protector technology is not a rule.Some tyres may be available in the same size in two versions - with and without a tyre rim protector.How is this possible?This is caused by the agreements between car makers and tyre manufacturers.If a given car manufacturer orders original equipment (OE) tyres for their car model, they may wish to have their tyres without the flanges (such tyres make it easier to install hubcaps).
Are the tyres with the tyre rim protector technology worth it?
Most of the standard tyres (above profile 55) do not have any protection, as they are often installed on steel rims.Even though it may seem like an omission at the beginning, this is due to the fact that most steel rims use hubcaps to enhance their appearance.
The lack of a tyre rim protector provides greater flexibility when installing the hubcap and installing the tyre on the rim.
Tyre rim protection is manufactured using different technologies, depending on the manufacturer.Some may have a raised rib tightly fitted against the bead in the lower part of the sidewall, or a receded bead, which partially clasps the fringe.Others have a thicker rib where the tyre is widest (the distance between sidewalls in the widest place).
A raised rib adjacent to the bead or a deeply receded bead is primarily there to protect the low profile tyres and aluminum rims against accidental damage.
In tyres used in light off road vehicles, rim protection also helps to protect the tyre and the rim against dirt and damage by stones, tree trunks and other off-road obstacles
Tyres with one or more raised ribs at the spot of maximum width are often used in delivery trucks and trailers.The additional thickness of rubber at such spot protects the sidewall from damage and increases the amount of rubber that has to be worn off before multiple abrasion by the curb causes cuts or reveals the internal cords.
Regardless of the naming, which depends on the manufacturer, the purpose of all tyre rim protectior devices is basically the same.They are there to protect the internal structure of the sidewall and cover the rim fringe against mechanical damage.
Tyre rim protector names with different manufacturers
In Goodyear tyres
RFP (Rim Fringe Protector)
FP (Fringe Protector)
MFS (Maximum Flange Shield) used by Dunlop
In Continental tyres
FR - Felgen Ripen – a rim-protecting ring
In Pirelli tyres, the Cord name was used until recently to denote the rim protection on the sidewall, but it is no longer used.
In Bridgestone and Michelin tyres, even though tyres lower than profile 55 most often have some kind of fringe protection, the tyres themselves don’t bear any markings.