Asymmetric tyres | Directional tyres | MRT Technology | DSST and WARNAIR | TD tyres and rims | MFS | JLB | Aquaplaning | Abbreviations
Asymmetric tyres
An asymmetric tyre has different tread patterns on its inner and outer sides, giving it a distinct performance advantage over a tyre with a symmetrical or directional tread.
- The tread pattern on the inner side of a typical asymmetric tyre has more grooves giving better grip on wet roads
- The outer side has a higher plain surface area, the benefit of which becomes apparent when cornering at speed on a dry road
- A 'Temporary spare' is limited to 50 mph (80 kph)
- A car whose tyres are not fitted in accordance with the instructions on the sidewall will fail its MOT
- Some tyres are both asymmetrical and directional. These tyres carry markings on the sidewall which a) indicate the correct direction of rotation and b) identify the inner- and outward-facing sides. Failure to observe these instructions will impair tyre performance. The above recommendations will also apply.
(Reproduced by kind permission of the BRMA)
Directional Tyres
Designing a tyre tread which will operate equally well rotating in either direction inevitably involves compromises which limit ultimate performance in some respects.
Directional tyres, on the other hand, are designed to rotate in one direction only (indicated by a conspicuous arrow pointing in the direction of rotation on the sidewall along with the word "rotation"); so performance - wet grip, directional stability and handling - far from being compromised, is optimised.
Obviously, a directional tyre can deliver this improved performance only if it is correctly fitted to ensure that it rotates in the direction indicated on the sidewall.
What happens if you are unfortunate enough to have a puncture and your spare wheel is fitted with a directional tyre designed to rotate in the opposite direction to the tyre which it replaces? You are recommended to treat the spare wheel as a 'Temporary spare', drive at reduced speed and have the tyre correctly refitted as soon as possible.
(Reproduced by kind permission of the BRMA)
Multi Radius Tread (MRT) technology
The challenging task while developing the Dunlop SP Sport Maxx was to maximize dry handling without sacrificing aquaplaning resistance and comfort. This has been achieved thanks to Dunlop's exclusive Multi Radius Tread technology.
MRT Technology ensures a homogeneous pressure distribution in the contact patch, whilst simultaneously delivering a larger tyre foot print - delivering superior dry handling, without compromise in the wet.
SP Sport Maxx : Multi Radius Tread
As evident from the diagram (right), the advantage of MRT technology is that it quite literally results in more of the tyre being in contact with the road more of the time, when compared to less advanced systems.
(Dunlop Self-Supporting Technology) and WARNAIR
Advantages of the DSST technology:
- The patented sidewall construction carries the vehicle's weight even when the tyre is flat
- Special tyre construction with newly developed compounds and rubber mixtures avoids tyre destruction due to excessive flexing
- Even with a complete loss of pressure, acceleration, braking and steering behaviour remains unchanged
- Continued mobility up to a distance of 80 km / 50 miles at a maximum speed of 80 km/h / 50 mph in normal conditions
- DSST-tyres can be mounted on any standard rim
TD tyres and rims
The TD tyre and rim concept is a synthesis of two previous millimetric tyre and wheel designs, the DL (Denloc) rim used with Dunlop Denevo tyres and the Michelin TR rim used with Michelin TR tyres. The TD rim incorporates a groove which accommodates the enlarged bead toe of TD tyres and ensures that steering control can be maintained in the event of a tyre deflation.
The following notes should be observed when servicing TD tyres.- In an emergency an equivalent dimension TR millimetric tyre can be fitted to a TD rim.
Warning: TD tyres cannot be fitted to TR rims. TD tyres must only be fitted to TD rims. - Under no circumstances may an inner tube be used in conjunction with either a TD or TR tyre.
- When fitting or stripping TD tyres apply approved silicone-free aqueous lubricating fluid harmless to tyres.
Maximum Flange Shield
The Dunlop MFS (maximum flange shield) system protects expensive alloy wheelsfrom kerbing.
A profile of rubber runs around the circumference of the tyre, located low on the side wall above the wheel flange creating a buffer zone.
Jointless Nylon Bandage
Prevents the tyre from expanding at high speed and ensures an even and wide contact area at all speed levels.
Aquaplaning
Further improvement of aquaplaning safety
The Dunlop SP Sport 01 facilitates low-turbulence water drainage; longitudinal grooves without cross-cuts.
SP Sport 2000
SP Sport 1
Aquaplaning is the phenomenon of tyres floating on water and losing all braking grip.
Comparison test on glass plate.
Speed 80 km/h, depth of water 7mm.
The glass plate illustrates the improvement in water drainage.
SP Sport 2000
SP Sport 1
Abbreviations
| BLT | Raised Black Lettering | NRM | Normal load |
| DOT | Department of Transportation (DOT) code on tyre walls | OWL | Outlined White Lettering |
| EC | 'E' number marked on sidewall | RF | Reinforced |
| FUL | Full Load | RWL | Raised White Lettering |
| HSN | High speed use at normal load | SL | Slim Line White Lettering |
| HFS | High speed use at full load | TL | Tubeless Tyre |
| LR | Low Rolling Resistance | TT | Tubed Type Tyre |
