MICHELIN PILOT POWER the New Michelin Hypersport Tyre, Born in Competition
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MICHELIN PILOT POWER The New Michelin Hypersport tyre, born in competition. Michelin Pilot Power : - Its advantages....................................................................................... Page 2 - Benefiting from a number of components previously reserved for MotoGP................................................................................................ Pages 3-4 - A tread pattern with a very low void ratio and a design that enhances its sporting feel.................................................................... Pages 5-7 - A specific profile and construction..................................................... Pages 8-9 1 Advantages of the Michelin Pilot Power · Exceptional dry and wet grip - Very soft rubber: Shore hardness measurements – 58 – confirm that the Michelin Pilot Power is the softest of the hypersport tyres currently available on the market. It is 6% softer than its nearest competitor. Michelin’s unique compound mixes and use of 100% silica ensures that there is no compromise in terms of durability, that is normally associated with soft compound tyres. Source : At Michelin’s Research and Development Centre, shore hardness measurements have confirmed that the 180/55 ZR 17 tyre is at the same level as the rest of the Pilot Power range. This technique consists of measuring the resistance of the rubber with a calibrated truncated cone plunger with a steel blade corresponding to a hardness of 100. All measurements of rubber compounds provide comparative values if the tests are performed under the same temperature conditions. The lower the figure, the softer the rubber. - A very low void ratio: The measurements of a triangulation laser* at the research and testing centre in Ladoux confirm the very low void ratio of the Michelin Pilot Power with respect to competitors’ tyres. The Michelin Pilot Power has a very low void ratio of 13.28% at the front and 11.58% at the rear. *Test conditions: - Rim for testing: 3.50x17 for the 120/70ZR17 and 5.50x17 for the 180/55ZR17. Inflation pressure front=2.5b and rear = 2.9b · Reduced warm-up times The Michelin Pilot Power owes its quick warm-up time to the advances made in this area with respect to MotoGP tyres. In fact, the Michelin Pilot Power benefits from a rubber compound used in MotoGP over the past two years. · Easy handling, improved rider feedback and maximum lean angles The new front profile of the Michelin Pilot Power, derived from the MotoGP tyre, as well as its specific construction and rubber compounds, has led to considerable progress in terms of handling and high-speed stability. The combination of all these characteristics also provides better feedback and a more progressive performance whilst cornering. 2 Benefiting from a number of components until now reserved exclusively for MotoGP Rubber and grip: Tyres are made of rubber or elastomers to which they owe much of their gripping capacity: The production of a rubber compound requires more than 200 components, which is why the rubber compounds of tyres are called mixes. These are natural and/or synthetic elastomers, sulphur, reinforcing fillers (carbon black, silica) and a number of other materials with diverse properties (formulation additives such as protection agents, vulcanising agents, etc.). Classed as an elastomer, rubber may be synthetic or natural. Once vulcanised the rubber provides the visco-elastic properties of the mix. Unlike elastic material, a visco-elastic material, when deformed, returns to its original shape, but only after a certain period of time. This is the phenomenon of hysteresis. Increased hysteresis leads to better grip. The purpose of the synthetic rubber manufactured in Michelin’s Bassens factory and used for the Michelin Pilot Power is to make the compound more hysteretic, thus improving its grip capabilities. When they are mixed with elastomers, reinforcing fillers such as carbon black and silica also contribute to increased tyre grip. In addition to its properties which are identical to those of carbon black (wear-resistance and ultra-violet resistance), silica also improves grip on cold surfaces. The interaction of reinforcing fillers with elastomer chains is the major factor in the tyre's performance, particularly with respect to grip. Unlike carbon black, silica does not interact naturally with the elastomer chains. It is therefore necessary to introduce a chemical "bonding" agent. To make the blend of silica and the other components as uniform as possible, especially with the elastomers, Michelin selects the finest silica. The silica bonding agent and the mixing procedure are exclusive to Michelin. The grip properties of the rubber will depend on the uniformity of the rubber mix. In the motorcycle tyre domain, ultra-fine silica provides increased grip while maintaining wear resistance. A rubber compound directly from the competition for Michelin Pilot Power Michelin Pilot Power is the first production tyre to benefit from a rubber compound formula specific to competition tyres: C-RAO (Compounds-RAcing Optimisation). The grip properties of the Michelin Pilot Power rubber compound, and in particular its quick warm-up time, result essentially from a combination of three 100% synthetic components, identical to those used for MotoGP tyres: 3 · Formula additives such as macro-molecular components (MMC) and high-technology synthetic components (HSTC), used in MotoGP in 2002/2003. This compound will be used to characterise the rigidity level and the performance of the rubber (warm-up time). · 100% synthetic elastomers exclusive to Michelin, originating from MotoGP (MRSE – Michelin Racing Synthetic Elastomers), also used in MotoGP in 2003. Michelin's expertise in mixing elastomers with other materials makes all the difference. These mixes were created and developed by Michelin. The Michelin Pilot Power also owes its uniqueness to specific rubber compounds. The rubber compound for the rear tyre was developed to handle the engine torque. The front rubber mix, meanwhile, was designed to ensure that the steering axle transmits the trajectory accurately. The Michelin Pilot Power is the softest tyre in its category and does not compromise longevity. Softer rubber is better at compensating for unevenness of the road/track surface. This is why the Michelin Pilot Power provides excellent grip on wet and dry surfaces. The Michelin Pilot Power also owes its very short warm-up time to its rubber compound, which remains soft even at low temperatures. Until now, the use of soft compounds resulted in rapid tread wear. The revolutionary Pilot Power has spectacularly improved the grip, whilst preserving the longevity of the tyre. This is due to the use of ultra fine silica, new additives and synthetic elastomers. 4 A tread with a very low void ratio and a design that enhances its sporting characteristics Role of the tread pattern: ð Water evacuation: The presence of water interferes with the grip mechanism. In wet conditions, to maintain grip water must be evacuated to give dry contact between the tread and the road surface. A tyre's tread is made up of drainage channels called grooves that evacuate water. The tread pattern dries the road beneath the tread so that it can make contact with and grip the surface. It breaks the film of water that accumulates in front of the tyre, stores the water in the grooves, and in a few thousandths of seconds, ejects the water away from the contact area. The grip mechanism: Zone 1: Aquaplaning Water height > 0.5 to 2 mm Zone 2: Viscoplaning 10µm < Water height < 0.5 to 2 mm Zone 3: Wet and dry Water height < 10µm 5 Zone 1 : The evacuation of standing water is ensured by the tyre’s bow-shaped footprint, which mimics the bow of a ship as it cuts through the water. Zone 2: A small amount of water under the tread remains to be evacuated: this is the role of the tread grooves. Breaking this remaining film of water will enable the rubber to contact the road. Zone 3: This break is ensured by the edge of the tread grooves cutting through the film to the road. A bow-shaped footprint ð Tyre rigidity: During riding, tyres undergo deformations due to speed, the load/weight of the motorcycle and the road surface. The rigidity of the tyre affects the level of deformation and guarantees road grip when riding at high speed. Like the casing, the tyre’s tread also affects the rigidity level. A very low void ratio encourages greater tyre rigidity. The particularly soft Michelin Pilot Power rubber compound is the reason that the tyre can perform in all conditions despite its very low void ratio. The Pilot Power design enhances its sporting characteristics The tyre tread design also expresses the tyre's performance. After looking at the tread, the motorcycle rider will quickly form a first impression of the tyre. ð Measures taken by the designers: - A tyre that follows the same trend as motorcycles: The hypersport market is changing radically. Motorcycles are approaching the one bhp to one kilo power to weight ratio. Tyres must respond to increasingly stringent technical and aesthetic requirements. - New tyre, new tread: its fluid lines must express its high performance character for sports riding under extreme conditions. - Raw, taut lines: no more soft " curves " and bowed forms 6 KATANA cut ((centrall grooves)) Speed enhancement on straights Clean cuts between grooves Non-parallel lines SAII cuts ((llaterall grooves)) Grip through corners Smooth curves Asian culture was the main inspiration for the designers who designed and presented the tread to convey the impression of the Michelin Pilot Power's speed and precision. The shape of the central grooves (KATANA sword thrusts) evokes the Michelin Pilot Power's sporting side and its performance characteristics. The fact they are separate, unlike the transversal grooves on the Pilot Sport, conveys the guiding effect, aquaplaning performance and optimised contact area. The lateral grooves (SAI shape), which flare in the centre of the tread band, with their bevelled end also contribute to the excellent handling of Pilot Power on wet surfaces.