Q What is silica and why is it now so common in bike tyres?
Answered by Mark Sears, Motorcycle Product Support Manager for Dunlop
Silica, otherwise known as silicon dioxide, is a major constituent of sand, so there is plenty of it around. It is an ingredient used primarily to deliver wet-weather performance and provide flexibility through lowheat build-up.
Silica is used widely, but it wears quite fast, so it needs to be mixed with a substance called ‘carbon black’ to suppress wear rates whilst silica provides traction in the wet.
Tyres with performance credentials in wet conditions, such as our new Dunlop Roadsmart III, use more silica than carbon black, while a road/track tyre such as our Dunlop D212 GP Pro would have a higher level of oil and carbon black.
Silica was introduced to motorcycle tyres in the early ’90s and was first seen in the racing arena, where it was one of the key factors in reducing lap times in the wet. For example, if a rider was achieving a 1min 30sec lap time in dry conditions with a slick tyre, he would be able to achieve within 10% of this lap time in wet conditions using a wet tyre with silica. Lap times improved by 2-3 secs straight away and the extra grip made sharper profiles possible.
This technology quickly made its way into road going products and as bikes have become more and more powerful, silica is playing a major role in transmitting the power.
Today’s brilliant wet weather grip performance is made possible by silica