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      07-09-2013, 08:58 PM   #2
djej
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Post First BMW i3 drive reviews (Edmunds and Drive.com)

http://news.drive.com.au/drive/new-c...710-2pp3q.html

Radical electric car is fun to drive and funky to look at.

Forget everything you ever thought about electric cars; BMW's i3 is a sign of things to come.

First previewed in concept car form back in 2011, the highly contemporary four seat hatchback has now progressed to pre-production stage with Australian sales slated to begin in 2014 as part of a worldwide roll out for BMW’s i brand.

The i3 is the first road-going BMW model to be based around a body structure constructed entirely out of carbon fibre.

BMW says the use of carbon fibre within the structure of the i3 has not only helped in achieving an impressively low - by electric car standards - 1195kg kerb weight, but also provided greater scope with its overall performance potential by allowing the use of a smaller capacity battery than would have been possible with more conventional steel monocoque construction like that used by its more traditional models.

Stylistically, the production version of the i3 differs little to the most recent concept of the new four seater. It is a modern looking car boasting proportions not unlike those of the Mercedes-Benz B-Class but with a much more contemporary appearance. The lack of B-pillars (the pillars at the side between the front and rear doors) has allowed the use of coach doors at the rear to provide excellent access to the rear quarters.

Power comes from a 125kW electric motor mounted low down within the rear axle assembly – a position that has allowed BMW to devote the entire space under the bonnet to improve crash worthiness.

But as with all electric cars, it is the torque rating that really counts. With 250Nm, BMW’s first ever series production electric car boasts 10Nm more than the turbocharged 1.6-litre four-cylinder petrol powered Mini Cooper S, and it arrives 1600rpm earlier, from the very first degree of throttle travel. It is all sent to the rear wheels via a single ratio gearbox that offers the choice between a trio of driving modes: Comfort, ECO-PRO and ECO-PRO+.

BMW’s efforts in keeping weight in check are clearly reflected in the official acceleration claims which see the i3 dash from 0-60km/h in 3.8sec and 0-100km/h in 7.2sec – figures which see it burst out of the blocks and achieve typical urban speeds with greater gusto but pretty well on par with the Mini Cooper S to the traditional benchmark. Top speed is limited to 150km/h, at which the engine is pulling a maximum 11,400rpm, to protect the state of charge and subsequently its range.

On that important subject, the new BMW is claimed to provide an overall range of up to 190km on a single battery charge, although this should only be taken as a rough guide to the sort of distance it is actually capable of achieving. BMW’s own real world projections are altogether less optimistic at 130km in wintery conditions but 200km in summer climates. Still, they are well within the 41km average daily commute the German car maker has identified in worldwide customer trials of the Mini E and BMW 1-Series ActiveE – the latter of which ran the same basic driveline as the i3. As it is, BMW describes the i3’s range as being “adequate to meet the day to day mobility needs of the target customers”.

To allay any lingering uncertainty these customers might have about stepping from a traditional petrol, diesel or hybrid into the fledgling ranks of electric propulsion, BMW will offer the i3 with a range extender (REX) option by way of a modified version of the 650cc two-cylinder petrol engine used in the company’s CT650 GT motorcycle with a nine litre fuel tank sited low down ahead of the front seats in the space usually dedicated to the gearbox in a conventional front-engined car. This is likely to be the only option available in Australia when the i3 arrives next year.

Mounted next to the electric motor underneath the boot floor at the rear, the combustion engine has been tuned to operate at up to 4300rpm. It acts purely as a generator to provide electricity to the battery. Unlike the system used by the Holden Volt, it does not provide direct drive of any kind, which is a first for a series production electric car. So configured, the new BMW is claimed to provide a range of up to 300km.

The 22kWh battery used to power the i3’s electric motor is produced by Samsung and comes with a warranty that is valid for up to eight years or 100,000km. Claimed to weigh 230kg, it consists of 96 individual cells mounted low down across the entire length and width of the car’s flat floor. BMW says the lithium ion unit, which operates at 360 volts, has been designed to allow replacement of damaged cells and is kept at an optimum operating temperature of 20 degrees Celsius by an individual air conditioning unit.

Recharging times for the i3 vary quite dramatically depending on the strength of charge available at an individual property or charging station. BMW offers a so-called wall box charger that in its most basic 2kW configuration is claimed to provide a full charge within six hours. When plugged into a contemporary 40kW fast charge station the battery can be charged from 20 per cent to 80 per cent capacity within 30 minutes, according to BMW. Interestingly, field studies with the Mini E and 1-series ActiveE determined that 90 per cent of charging was carried out at private residences.

Underneath, the i3 uses a bespoke chassis that is claimed to boast a typical-for-BMW perfectly balanced 50:50 front-to-rear weight distribution. The front end is supported by MacPherson struts while the rear end uses a five link arrangement that mounts directly to the bell housing of the electric motor. Within the generously dimensioned wheelhouses are standard 19-inch forged aluminium wheels shod with relatively narrow 155/70 profile tyres – a combination that BMW claims not only provides weight savings for low unsprung masses but excellent aerodynamic properties and extremely low rolling resistance.

Getting in the i3 you step up over substantial sills and sit rather high by traditional BMW standards. The seat squab is mounted a considerable 170mm higher than that in the 1-Series at 670mm from the ground, placing your shoulders well above the waistline and providing a commanding view of the road. It is even 90mm higher than the seat in the X1, so you sit at genuine SUV height.

The seats themselves offer little in the way of lateral support within the squab but they possess firm cushioning and feature a deeply dished backrest with integrated headrests. There is no electronic seat adjustment. And there won’t be, even as an option. Such a modern day luxury would require electricity that could otherwise be used to extend range, argues BMW. Manual seat adjustment it is, then.

The interior layout is unlike any other from the German car maker with heavily raked windscreen, deep dashboard devoid of any traditional centre stack and a completely flat floor – all of which gives the i3 a feel that is oddly reminiscent of the old Mercedes-Benz A-Class in many respects, at least from the front seats.

The new BMW provides ample room for four adults, although the rear windows are fixed and the rear seat is not much than a mere bench with adequate but far from outstanding levels of legroom. The boot is also quite small and boasts a rather high loading lip owing to the state-of-the-art driveline sited beneath it.

It is a thoroughly modern driving environment dominated by the horizontal themed dashboard, a steering wheel that is not as vertically mounted as in other BMW models and upright seating.

The main control takes the form of a pod which extends out from the steering column and sits well within your line of sight, housing the starter button, park mechanism and gear shifter – forward for D; middle position for N; backwards for R. There’s also a second cluster of controls down between the front seats, including a new take on BMW’s iDrive rotary controller, a mechanism for an electronic park brake and the all-important switch to alter the drive mode – very much the key to balancing performance and range.

Pressing the start button (instead of turning a key) and then nudging the gear lever forward (rather than drawing a lever backwards) with the palm of your hand selecting D in one movement feels very intuitive – and distinctly new world. There is a faint whine from the electric motor as we get underway but apart from the distant sound of the tyres rolling across the bitumen the cabin is pleasantly hushed. In the first kilometre or two, it is the directness of the steering, a variable ratio system tuned at a nominal 2.5 turns lock-to-lock, that gets our attention. The electro-hydraulic system, closely related to the set-up to be adopted on the new Mini hatchback due to make its world premiere at the Los Angeles motor show later this year, is terrifically weighted for a car conceived primarily for urban driving, and unlike some systems it is also keen to self centre. The fact that the front wheels are not asked to channel any power clearly helps.

Thanks to its relatively low weight, the i3 offers instantaneous acceleration and entertaining pace up to and beyond typical city speed limits. The official performance claims appear entirely conventional for a car of this size, but the reality of the whole 250Nm being delivered to the rear wheels the very moment you brush the throttle relates to genuinely urgent properties – the sort you just don’t get with a traditional petrol or diesel powered car.

The default driving mode is “Comfort”, which is designed to provide maximum performance up to 150km/h. The rate of energy recuperation, and with it the braking effect on a trailing throttle, depends on the mode you choose. Backing away from the throttle in ECO-PRO+, the most efficient of the three driving modes, provides quite aggressive levels of retardation as the electric motor is used as a generator to collect kinetic energy on the overrun; so much so that you rarely need more than a fleeting dab of the brakes.

The energy recuperation system is so assertive in its action, BMW has programmed the brake lights to illuminate if it causes the i3 to decelerate abruptly, something it says would only ever occur on downhill runs. As well as calling up the most aggressive energy recuperation, ECO PRO+ mode also limits top speed to 80km/h, reduces the performance of the air conditioning system in a bid to save electric charge and, in combination with a wide range of navigation features, will also route you on roads with favourable topography in a bid to provide the maximum possible range.

The combination of such strong accelerative properties, a seamless power delivery and an energy recuperation system you can rely upon to provide an instant braking effect the moment you come off the throttle gives the impression that the i3 will be a terrific city car. We’ve only driven it on a test track, but our limited test drive revealed it possesses all the likeable traits of the earlier Mini E and 1-series ActiveE, but with even more impressive performance, added range and a far more commanding driving position.

But this is not the best it has to offer. Sheer agility is the defining characteristic of the i3. With its lightweight carbon fibre body structure and lithium ion batteries mounted as low as possible underneath the floor, the new BMW boasts a centre of gravity that, at 470mm from the ground, is described as being close to that of the X1. Combine this with typical rear wheel drive dynamic qualities and the super responsive driveline and you have the ingredients for a truly engaging drive.

There is a noticeable degree of roll when you throw it into tightening corners at higher speeds. The tall but almost comically narrow tyres provide a surprising amount of grip, allowing you to edge up to the point where purchase begins to fade with a tell tale squeal with a fair deal of confidence before the DSC (dynamic stability control) is set into action.

We’ll need more time behind the wheel on public roads before we can deliver any confident appraisal of ride quality. On the rougher road surfaces around the periphery of the BMW test track where we drove it, the i3 hinted its relatively long wheel base, high aspect ratio tyres and generous wheel travel provides the basis for a more comfort oriented feel than recent BMW models. There’s no obvious fidgeting over smaller ridges, although the jury is still out on its ability to cope with bigger bumps.

Pricing is yet to be announced, although officials suggest the i3 will land here at around $60,000. The range extender option, something BMW’s studies suggest won’t be required by many potential customers but will clearly be sought after for peace of mind, will likely add a further $5000 at least.

Those in the market for an electric car are aware of their limitations. But ultimately there are very few with the new BMW. The i3 is not a family car – not in the traditional sense, anyway. It is a highly individual but inherently practical and fun to drive alternative to existing city cars.
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