BMW’s One series coupe is a handsome looking car. It has that easily identified styling that makes it immediately recognisable as a member of the BMW family. Inside it does what every good coupe should do, in that it provides comfortable accommodation for four people. Of course it helps if the two rear seat occupants are young and agile, as getting in and out, is a lot more difficult, than in a car with four passenger doors.
In its normal size, the luggage boot is of a size that compares favourably with cars in the medium size class. When you need additional space, the rear seat backrest is divided 60/40 and folds down onto the seat cushion, which more than doubles the luggage space available, but naturally at the expense of passenger accommodation.
Its overall size makes it a handy urban runabout, while its comfort and performance should make it the perfect touring car BUT ! Like all BMWs the 123d coupe is rear wheel drive and the space below the luggage floor is allocated to the battery and other electrical components. There is no spare wheel. BMW say that a spare tyre is not needed, as the car is fitted with runflat tyres.
If I review my motoring life, since I got my first driving licence when I was eighteen years of age, I can count the number of punctures on the fingers of my two hands. I had one car back in the nineteen sixties, that I had more punctures with, than I have ever had before or since, but when I changed the tyres to another make, that problem ceased. In the light of this you may well ask, as BMW do, whether a spare wheel is necessary at all, especially if you can drive on the tyre when it is flat. Unfortunately in the recent past, whilst touring, on two occasions I got blow-outs, when the cars were loaded with all my touring baggage.
In the first instance the car concerned had one of those latex puncture kits. Unfortunately latex does not cure a blow-out, so I had to avail of the AA rescue service, which put the car up on the back of a transporter and took us all the way from south west Scotland to north east England. More recently whilst travelling from Wales to the south of England, I got a blow-out on a motorway. The car concerned had a Spacesaver spare wheel, but trying to keep below fifty mph on a UK motorway, is frightening to say the least. However, that was the easy part. Driving slowly on a narrow country road is a nightmare, especially as you build up a very irate convoy of motorists behind you. On both occasions it was late afternoon with evening and nightfall approaching, so it was not simply a matter of dropping into the nearest tyre centre, assuming I knew where it was and buying a new tyre. For piece of mind when touring, I am convinced, that a full size spare wheel and tyre is essential ! Of course, BMW have a problem here, as the car had different size tyres on the front and back wheels.

BMW have a reputation for building, thoroughbred sporting machinery. In recent times they have been very successful with their Efficient Dynamics programme. As a result of this the 123d diesel, with the six speed manual transmission, can deliver an urban fuel consumption of 43 mpg (6.5 lt/100 km), which stretches to 64 mpg (4.4 lt/100 km) on the extra urban cycle and averages out at 54 mpg (5.2 lt/100 km) on the combined. While doing that it can still offer a top speed of 238 kph (148 mph) and a 0-100 kph acceleration time of 7.0 seconds. All that and exhaust emissions of 138 gm/km. That is impressive ! That exhaust emissions figure puts the 123d coupe in the Euro 150 p.a. road tax bracket, at current rates.
So how does it manage those performances ? It is all down to what BMW call Efficient Dynamics. When you stop at the traffic lights or in traffic and put the car into neutral, the engine automatically switches off. It restarts as soon as you depress the clutch pedal to shift into gear. The alternator only charges when braking, decelerating or when it is actually needed to top up the battery. Thus no driving power is absorbed unless it is absolutely essential. Gear ratios have been adjusted to give lower engine speeds, especially when in the higher gears. In the case of the 123d this has been very skilfully done, so that the engine does not drop below its normal point of useful torque, when slowing down temporarily.

Earlier I mentioned that different size tyres are fitted front and rear. These are ultra low profile with 40 in the front and 35 at the rear. On Fingal and north Dublin’s roads, the ride is very hard and uncomfortable. Every little ripple, wave, undulation, as well as every pothole and crater are transmitted through to the car. Whether this is due to those ultra low profile tyres, or whether it is due to the spring rates, I do not know. What I do know is that on smooth roads, of the sort one expects in a civilised society, the 123d glides along as if on a magic carpet. However, on Fingal and north Dublin roads, you need to make absolutely sure, that your false teeth are well cemented in, otherwise they will be dislodged several times in every kilometre.
The steering is nicely firm and direct. It is geared to give three turns from lock to lock, which is leaning towards the comfort zone, rather than the sporty zone, yet it gives a positive feel to the driver. The whole steering sensation is helped by the excellent quality and feel of the leather covered steering wheel. The gearchange likewise, has a very positive and quality feel to it. I must admit that I would probably have preferred the alternative automatic transmission, but to do so would incur certain penalties. While the top speed and 0-100 kph acceleration time are insignificantly different, the exhaust emissions are 10 gm/km higher, sufficient to move the car up into a Euro 290 p.a. road tax band, at present rates.
The engine’s performance is impressive, with a specific output of 75.187 kW/lt. To achieve that figure BMW fit twin turbochargers. A small lightweight turbine needs very little energy to keep it revolving. This does away with any turbo lag and once spinning the power it helps to generate, quickly gets a larger turbine spinning, to give a smooth and powerful boost. Fuel is injected directly into the combustion chambers at a pressure of 2000 bar and the injectors themselves are capable of several timed injections per combustion stroke. Interestingly, although it is a diesel, it runs at a comparatively low, for a diesel, compression ratio of 16 : 1.
In order for a driver to be able to enjoy the car’s performance to the full, he/she needs to know that there is an effective braking system at their disposal, to keep the driving safe, and enjoyable. The 123d coupe has large 330 mm ventilated discs at the front and generous 300 ventilated discs at the back. The system includes anti-lock, cornering brake control, dynamic stability and traction control and automatic stability control.

Above and below : Severe rust on brakes, callipers and wheel hubs, rear and front

However, when examining the brakes and suspension, I discovered severe rusting on the wheel hubs, callipers and brake discs. This is totally unacceptable on a car that is at the most a few months old and has under 10,000 km (6,300 miles) on the odometer. It is insulting to say the least, on a car with a list price in excess of Euro 50,000 and purporting to be a quality car.

Inside the car was finished in black, with bits of silver trim on things like the door handles and the facia to brighten up the sombre blackness. While black would most certainly not have been my preferred choice, I would be able to live with it if I had to. The two front seats were very comfortable, with well bolstered sides to hold you firmly in place. Both front seats were fitted with the optional extra heating which costs an additional Euro 460. The backrests on both front seats tilt and then the whole seat slides forwards to facilitate entry and exit to the two, individual rear seats.

The hooded instrument binnacle contains the speedometer, tachometer and fuel gauge. Generally speaking all three are easy to see whilst driving. The centre console houses the audio equipment and the air conditioning. Again these are generally easy to see and use whilst driving. The steering wheel had controls for the audio, as well as the Bluetooth telephone installation. The Bluetooth installation adds Euro 1,075 to the price and the test car also had an optional USB/audio interface (Euro 420) and a special BMW radio/CD (Euro 295) installed. I am not so sure about paying Euro 310 extra for the privacy glass on the rear side windows, as I found that it inhibited visibility when exiting at a shallow angle from a side street, into the main traffic flow. Automatically dimming interior and exterior rear view mirrors are probably a good safety feature, so I would expect them to be fitted as standard on a car of this price and quality, rather than having to pay an extra Euro 445 for them. Cupholders are not high on my list of priorities, so I would definitely not pay Euro 60 for them, although I know people who find cupholders to be an essential part of the equipment. The parking distance control is certainly a useful feature, in this day of parking bays that are far too narrow and the number of cars that are badly parked in said narrow bays. On the other hand Euro 430 does appear to be a bit steep for such a gadget. However, if simple floor mats add Euro 145 to the price, perhaps that parking distance controller is not overpriced after all.

Technical data