The radial revolution
A revolutionary construction for unrivalled performance...
Thanks to its X tyre with radial casing plies, Michelin set out to conquer the world with a considerable advance in technology.
Its revolutionary construction for the time had the special feature of separating the sidewall function from the crown function.
|Dimension||Seat||Sculpture||TT/TL||Load Index||Speed Code||Section width (mm)||Outside diameter||Circ. bearing||Rim width (mini-maxi)||Tube|
|125 R 12||12''||X||TL||62||S||132||518||1555||3.0 3.5 4.0||12 C 13|
|7.25 R 13||13''||X||TT||90||S||180||654||1988||5.0 5.5 6.0||13 F 13|
|155 R 14||14"'||X||TL||82||T||157||604||1831||4.0 4.5 5.0||14 F 13|
|125 R 15||15''||X||TL||68||S||127||598||1818||3.0 3.5 4.0||14 D 13|
|155 R 15||15''||X||TL||82||T||157||630||1910||4.0 4.5 5.0||15 E 13|
|125 R 400||400mm||X||TT||69||S||130||619||1882||125 135||16 C 13|
|135 R 400||400mm||X||TT||73||S||138||631||1918||125 135 145||16 C 13|
|145 R 400||400mm||X||TT||79||S||142||649||1973||145 155||16 E 13|
|155 R 400||400mm||X||TT||83||S||150||660||2006||145 155 165||16 E 13|
|165 R 400||400mm||X||TT||87||S||162||677||2059||155 165 185||16 F RET|
|185 R 400||400mm||X||TT||91||S||185||707||2149||165 185||16 F RET|
|5.50 R 16||16''||X||TT||84||H||172||690||2088||4.5 5.0 6.0||16 F RET|
|185 R 16||16''||X||TT||92||S||180||707||2139||4.5 5.5 6.0||16 F RET|
The benefits of the radial tyre compared with the standard tyre were visible in all areas:
- greater safety: clearly improved road-holding, grip, braking.
- economical to use: double the mileage, significantly reduced fuel consumption.
- increased comfort thanks to sidewall flexibility.
In the 1950s, the superiority of the X tyre was such that a number of racing drivers adopted it, although Michelin was not officially involved in car racing.
The adventure of
The radial tyre was the first major innovation from Michelin and was initially marketed as the “X” tyre in 1949.
Lancia was the first car manufacturer to fit the X tyre as original equipment on the Aurelia model.
From 1955 onwards, radial technology became increasingly popular and the majority of European car manufacturers opted for this solution.
The X could be fitted to cars of very different categories, from the original and popular 2CV or Beetle to the fascinating Mercedes 190SL or Facel Vega.