Michelin Primacy 3 ST: Good stopping Asia-Pacific Tyre

By Lee Pang Seng
MICHELIN has come to terms with meeting regional needs for tyre performance and has introduced its new Primacy 3 range (which is the third generation tyre) as a dedicated product for Asia-Pacific markets. It carries the additional ‘ST’ alphabets, which stands for ‘Silence Tuned’.

The French tyre maker has determined through market feedback that car owners in this part of the world generally value a quiet running tyre that also provides a comfortable ride. It realises that it would be more cost effective and practical to tailor an existing product than to produce a global tyre at a higher cost.

While there is no mention of the difference in tyre price between the Primacy 3 that is sold in Europe and the Primacy 3 ST, Michelin has decided that the tyres would not be sold alongside each other. Where the Primacy 3 is sold, you would not find the Primacy 3 ST, and vice versa.

For cars imported to Asia-Pacific countries (which do not include China) with Primacy 3 tyres, Michelin recommends that the car owner change to the Primacy 3 ST when the tyres are worn or damaged. According to Pierre Azemat, Product Marketing Manager, Southeast Asia & Oceania, there is no difference in the level of tyre performance between the two, except that the ST offers more with a quieter and more comfortable ride. Strangely though, the Primacy 3 ST tyre is not made available in all Asean countries, save for Malaysia, Thailand and a few others.

The Primacy 3 ST was honed by Michelin Japan in the tyre tread pattern and compounds within the technological boundaries that were applied in the Primacy 3. This was headed by Fumitaka Nemeto, Senior Tyre Design Engineer, who moved over from the SUV tyre department. He came in at the end of the Primacy 3 development and set about tweaking the tread pattern and compound to meet Asia-Pacific demands.

That saw 1.3 million kilometres of test over 18 months, including road trials involving fleet rental companies, in Asia-Pacific countries. Malaysia was one of them with a car fleet company running on Primacy 3 ST tyres on a six-month evaluation. The feedback from the Malaysian fleet was so supportive in all the areas of improvement that a clip was made quoting its drivers.

Michelin says its Japan facility also worked with Honda as part of the tyre development to come up with a Primacy 3 ST as an OE tyre for the new Accord (although we may not see that combination here as Honda Malaysia may toe CKD rules and use a locally produced tyre to arrive at a more competitively priced car).

The end result was a tyre that is said to stop almost three metres shorter in distance against a rival tyre; eight per cent quieter compared to other leading brands; and 25 per cent longer tread life over the predecessor Primacy LC. The Primacy 3 ST boasts of four new main technologies – FireMax, Stabiligrip, EvenPeak and CushionGuard.

FireMax is said to promote a safer ride through a combination of two features: flexible tread and chamfered tread blocks. The first item adapts to the shape of the road surface to provide better contact and grip, while the latter prevents tread blocks from distorting under pressure. This is an application of complementary technologies for a common goal: good road grip.

Stabiligrip adds to the good grip factor in both wet and dry: it features the use of self-locking bands in the small grooves between tread blocks. These ‘interlocking bands’ also minimise tread block deformation to improve handling on dry roads. On wet roads, the small grooves allow better dispersal of water for increased traction. Working hand-in-hand with the FireMax technology, Michelin says the Primacy 3 ST’s wet braking distance is 2.9 metres shorter compared to the average distance of ‘leading competitors’.

For a quieter ride, the EvenPeak technology is applied to the tread pattern. Tread patterns designed for safety performance usually generate more noise. Michelin says it has addressed this issue by designing tread blocks with a wider spectrum of sizes and positions on the outer shoulder. This is said to allow the noise generated to be spread across a wider frequency range, without noise peaking, leading to a quieter tyre. It does this without compromising handling or braking performance.

CushionGuard is the one that keeps ride smooth and comfortable. When the tread blocks make contact with the road, the FlexMax compound cushions the vibrations. Working together with the curved shock absorbent sidewall, it forms the CushionGuard technology. This does not give the tyre a rounder shoulder, thus maximising the tyre’s footprint on the road. What the new technology does is give the sidewall a greater ability to flex upon road impacts so that the harshness can be reduced. Again, Michelin says this is done without weakening the sidewall structure or compound. There is also a layer of noise-filtering rubber to diminish the vibrations.

Michelin Malaysia is focusing on the popular sizes, ranging from 15-inch to 17-inch, for executive cars Although the French tyre maker acknowledges that its tyres are not cheap, its market feedback has indicated that once a car owner has used them, he would continue to do so based on the positive experience. On the same token, market growth is also helped by this word-of-mouth promotion.

Michelin’s Bonanza Experience
Michelin arranged a drive experience for the regional media and dealers at the International Bonanza Speedway in the hill resort area of Khao Yai, about two hours’ drive to the east of Bangkok. Conducted over almost a month with successive groups, it involved a fleet of executive cars, including the new Mercedes-Benz A-Class and the latest Honda Accord.

All the tyres were replaced by new ones at the end of each day’s impression drive to ensure that the performance of the Primacy 3 ST would always be at its optimum level. The event covered four routines: wet grip and wet braking; dry handling; ride comfort and quiet drive; and a 10km-plus ‘scenic’ drive in the area.

We came away impressed by one aspect; the better stopping performance on wet road surfaces. That routine saw us driving Toyota Camry 2.0G, one with Primacy 3 ST and the other with a Thai-made tyre by a Japanese brand. We had about three laps each on a wet course with varying degrees of corners at speeds of 70 to 90km/h and a wet braking session during which we slammed on the brake pedal from a constant 85km/h.

Our average stopping distance was 1.6 metres, about half a car’s length, shorter than the Camry with rival tyres. That could easily decide between disaster and safe braking. The group’s average was almost three metres, which suggested that some of the media guys experienced even longer stopping distances between the two tyres. Grip-wise, the Primacy 3 ST held its own although we felt that the rival tyre had marginally better grip to give us a sharper turn-in into a corner. It’s safe to say that we were confident with both tyres through the wet corners at the recommended speeds.

The ‘scenic’ drive involved quite a mix of cars, including the new Accord, which we had the luck of the draw to pick. The exercise was to give us an idea of the tyre’s improved ride comfort running over normal roads. Our impression was coloured somewhat as we were distracted by getting a feel of the new Accord, both as a passenger and driver. We did drive over a few potholes to gauge the impacts, but we were not sure if it was the car’s better damping performance or the tyre’s improved absorbent quality, although it was more of a combination of both since they were developed to complement each other.

The ride comfort session was conducted ‘over a series of rumble strips’ back at the Bonanza circuit, with the ‘silent’ drive done on a short straight, during which the sound level inside the car was recorded. The cars involved were Camry 2.5G and the rival tyre was a different Japanese brand. Pierre says the approach was to compare against the best possible among the rivals in the Thai market.

We couldn’t quite discern the difference between the two tyres although our Thai co-driver pointed to the lower note of impact over the rumble strips and the softer cushioning with the Michelins. The ‘quiet’ drive was too short for us to gauge the reduction in noise intruding the cabin. The recorded decibel level, however, indicated a marginally lower noise level with the Primacy 3 ST tyres.

Rain almost ruined the dry handling routine. The light drizzle that took place left the track surfaces dry enough. It included taking a fairly sharp corner at 75km/h; an object avoidance course at about 70km/h; and a slalom course taken at 60km/h. This routine was conducted in Volvos S60 and the rival tyre was again the Thai-made Japanese brand.

It re-affirmed the impression that we had earlier during the wet handling session: we found the rival tyre’s grip to be marginally better as we could steer more accurately into the corner at the suggested speeds. Nevertheless, the Primacy 3 ST has all the positive qualities to win hearts over through first-hand experience.

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