Prior to the M749’s official debut at the Hanover IAA Commercial Vehicle show, Tyres & Accessories visited Bridgestone’s Aprilia proving ground to see the Japanese manufacturer’s new highway tyre in action.
Bridgestone’s latest drive axle offering is clearly presented to fight off the company’s number-one competitor, and therefore, it promises much. According to Bridgestone officials, the new M749 is more cost efficient because of superior mileage, excellent rolling resistance, and a “high capacity” for re-grooving and retreading. The demonstrations Bridgestone staff gave on the track were particularly designed to show the product also has strengths in “handling and wet safety.”
Technological developments were another consideration for the research and development team behind the new truck tyre. With up to 70% of long-haul vehicles now equipped with retarder systems, tyres today face enormous braking forces, which tend to deform tread blocks and lead to irregular wear.
Bridgestone engineers claim they have met this challenge head on by developing a new uni-directional tread pattern for the M749 with an asymmetric block design to combat excessive stress. The "closed" shoulder blocks use of tie-bars to increase block stiffness and help reduce block deformation to produce more uniform contact pressure distribution and more even wear.
During T&A’s Rome visit, Bridgestone UK commercial sales director Greg Ward gave a presentation on the particular benefits of the new tyre. Bridgestone’s simultaneous claims of both increased wet performance and better mileage were what really stood out.
According to Greg Ward, long-term mileage tests on the M749 conducted in Germany, France, Italy, the U.K. and the Benelux countries found that it out-performs “competitor A” (marked in blue on the powerpoint slides) by 10%. And of course this has a knock-on effect on costs per kilometre (CPK). In a further test conducted under the supervision of road transport consultant Roger Denniss, Bridgestone found that CPK was down by 6.1% against the same competitor. The tests were conducted over a three-year period between the third quarter of 2003 and 2006 on a truck travelling an average speed of 86 km/h with a 10.5 tonne load on the drive axle.
In addition, Bridgestone says the M749 outperforms its nearest competitor (which in every demonstration T&A saw was Michelin XDA 2E and XDA 2+E tyres) by 5% in braking distance and 8 per cent in wet cornering. These results are said to have been produced, at least in part, by the tyre’s unique tread design, which features five circumferential grooves and a combination of straight and s-shaped sipes. Bridgestone says noise emissions are minimised by ‘noise fences’ in the grooves, which dampen the noised caused by air pumping.
The M749’s casing construction is described as “extra-durable,” with a “high” capacity for retreading. The M749 went on the market in three sizes from September 2006, with further sizes to be added in 2007. It will also be available as a Bridgestone Qualitread retread tyre.
The introduction of the Bridgestone M749 highway drive-axle tyre follows the launch of the R249 steer-axle and R168 trailer-axle tyres, and is said to complete Bridgestone’s line-up of “new-generation” highway tyres.
U.K. fleet manager Duncan Platt concluded by presenting the truck product portfolio as part of the wider “total fleet management” services that Bridgestone provide. This includes fleet systems, tyre management, retread systems and the new tyre range.
If the technology T&A saw in action is anything to go by, the equipment behind Bridgestone’s total fleet systems is becoming increasingly advanced. The Tyre Inspection Module is already updated in real-time via the Internet with an integrated billing system, but new equipment means it is becoming more and more mobile.
Although no official time-scale has been set, Bridgestone is close to releasing a wireless tyre pressure monitoring system for use in fleet management. The system uses sensors embedded just under the tyre rim to send tyre pressure and temperature to a handheld device. This can then transmitted wirelessly to a palmtop or smart phone, and then uploaded to the Internet.
The handheld sensor has a very short range and “you basically have to walk up to each wheel.” Results can be exported in an Excel-compatible CSV data file. The in-tyre sensor is battery powered and, according to officials, has a projected lifetime of between 5 and 10 years. There are apparently no plans for a kinetically powered alternative system and Bridgestone representatives were wary of mentioning RFID.
Development of the system was originally announced back in September 2004 and is designed for truck and bus applications. European testing has been going on since January 2005 and trials are currently continuing in the U.K. and Holland.
Bridgestone’s Truck Point tyre management chain now has over 2,000 outlets across Europe including 274 in the U.K. Over 60 million euros has been invoiced via Bridgestone Total Fleet Systems in 13 nations, with over 95,000 tyres fitted online in 2005.
The new M749 will initially be available in three sizes 80 and 70 series sizes; 60 series sizes are scheduled to follow in 2007.