BMW M135i vs BMW 125i

What's the difference?

To answer the question of whether it matters that the new 1 Series is no longer rear-wheel drive, I say no it doesn’t. It may not be as romantic on the absolute limit, but it is better in every measurable way, and still feels distinctly BMW despite moving to the conventional layout of its rivals. 

Be sure to check out Mal’s video review from the 1 Series launch last December:

I’m the first to say the 1 Series is kind of the ugly duckling of the BMW family, but those looks grow on you, especially when you consider that this is exactly what a BMW hatch should look like. That this is one of the only rear-wheel-drive hatches left on the planet makes it even more special – and of course engaging to pilot. The downside is the price and the lack of value from a features perspective, plus safety could be bolstered with more technology. Still, anybody who likes to drive will commend you on your choice of a BMW.  

Yes, that kidney grille is rather large. If you want everyone to know you drive a BMW, you’ll love it. If not, get used to it. The X7, recent 7 Series update and upcoming 4 Series suggest they’re only going to get bigger. 

Nose aside, the 1 Series hatch has always had a distinctive, long-bonnet profile, which has generally been attributed to the rear-drive layout. Despite the move to a transverse engine, the new one is actually very close in proportions when compared side by side.

It’s just 5mm shorter in overall length and 13mm taller, with body width being the most notable change at 34mm wider. 

The key difference is that the front and rear wheels have been moved further back into the body, because of said engine layout change, and to make more back seat space in the rear.

Surprisingly for a model aimed at a younger demographic, the new 1 Series interior design isn’t quite the same step forward as the recent G20 3 Series.

It’s a cut above the X1 and X2 SUVS the new 1 Series shares its underpinnings with in terms of the shapes used, but is still classic understated BMW. 

However its headline act is the Live Cockpit driver display on both models, which gives you fully digital instrumentation and replaces traditional analogue gauges once and for all.

The 1 Series looks exactly how a BMW hatchback should. I know that sounds silly but what I mean is BMW could easily have designed something that was proportioned more like other hatches; that popular sort of bubble on wheels.

Instead, what you have is a hatch that retains BMW’s traditional attributes – there’s the long nose, the cabin set back, the high sides and the wheels placed almost at the very corners.

Seriously, look at the image of the orange 1 Series side on, now hold your out your hand and use it to cover just the windows – see, it looks just like a BMW 2 Series convertible. Does it look good? To me it does, right up until you get to the hatchback, and then it looks a bit awkward. But I do admire BMW’s designers for creating something unique looking.

That orange 120i ('Sunset Orange' is the official colour) is the most recent 1 Series I’ve tested. Those wheels aren’t standard, they’re 18-inch M ones and they are part of the optional 'M Sport Package', which also includes the body kit, complete with side skirts and the lower grille in gloss black.

The 1 Series is as affordable as BMWs get, but it’s still a real BMW. The cabin, for example, looks much like  every BMW, only smaller.

There’s the large, slab-like dash with the display sitting atop, below are the air vents and below that is the radio and then the climate-control dials. It’s a stack that’s kept its familiar order and shape on nearly all BMWs for what seems like forever.

The centre console has a similar layout as the one in a 3 Series or 5 Series or any Series, with the shifter and rotating media controller. Even the doors have the same design as those cars higher up in the BMW family, with the big moulded pockets and large pull handles.

The cabin isn’t as ‘blingy’ as the new Mercedes-Benz A-Class, but it’s not as plain as the Audi A3.

That steering wheel is part of the M-Package too, but the leather upholstery is a separate option.

The signs that this isn’t a more expensive BMW are the manual handbrake, the compact instrument cluster with analogue dials, the small dash-top display and the fact that  there’s a lot less real estate to be covered by trim pieces and material, which doesn’t have the same high-quality feel as those fancier models.

The cabin isn’t as ‘blingy’ as the new Mercedes-Benz A-Class, but it’s not as plain as the cockpit of an Audi A3 – it’s somewhere in between; refined and well designed.

At 4.3m end to end, the 1 Series is 16mm shorter that the A3 Sportback and 20mm narrower, at just over 1.7m across.

With my modest 172 cm height, I never had any trouble with the old model, but the new 1 Series is a bit more more spacious by all the important measures.

The back seat base and backrest are a bit flat though, which is probably to help the backrest fold almost flat, but probably not very supportive during hard cornering.

There's also no centre armrest in the back or cup holders, but you do get bottle holders in the doors.

You also get two ISOFIX child seat mounts and there’s two USB-C charge points in the back of the centre console, but there's no directional air vents unless you opt for the dual-zone climate control that comes standard with the M135i. 

The boot has grown by 20-litres to a pretty impressive 380 litres VDA which includes a very useful cavity under the floor instead of a spare tyre. An inflation kit is there for those duties. With the back seat folded flat, boot space expands to 1200 litres VDA. 

The 1 Series’ boot has a cargo capacity of 360 litres, which is more than the boot space of the Audi A3 Sportback (340 litres) but less than the new Mercedes-Benz A-Class’s 370 litres of luggage room.

What does that mean in real-world terms? It’s not a lot of space, and you might struggle to get a pram in, so check that  beforehand if you have small ones. That said, there was enough room for two carry-on sized bags, a computer bag and a scooter when my wife and I went on a weekend away with our four year old.

Space in the second row is also limited. Headroom isn’t too bad, but at 191cm tall I can’t sit behind my driving position without my knees digging into the seatback. I can just fit back there in the A3 and I have even more room for my knees in the A-Class.

Room up front is good with plenty of shoulder, head and elbow room for somebody my size.

Storage could be better: you’ll only find cup holders up front (two of them), the centre-console storage bin is small and so are the door pockets in the rear, but all is not lost because the door bottle holders in the front are massive, the glove box is a decent size and there are nets on the backs of the front seats.

It’s good to see directional air vents in the second row and a 12V power outlet, but there aren’t any USB ports back there – if you want to plug in a device there’s only one and it’s up front, along with another 12-volt outlet.

The rear doors appear large from the outside but the aperture to get in and out isn’t huge – again look at the images to see what I’m on about.

So, it’s a little BMW, does that mean the price is little? Nope. It’s like asking if a little Rolex is cheap. it might be cheap for a Rolex, but not for a watch in general, and it's the same for the 1 Series.

The 1 Series range starts at $39,990 for the petrol 118i, while its 118d diesel twin is $44,990. Both come with the standard Sport Line package, which adds 16-inch light alloy wheels and LED headlights, while in the cabin it brings cloth upholstery, sports seats and a leather sports steering wheel, high-gloss black trim and BMW scuff plates. Other standard features include a 6.5-inch display, with sat nav, reversing camera, six-speaker stereo, a digital radio and air-conditioning.

The 125i is only a tempting $3000 above the 120i at $49,990 and comes standard with the M Sport Package

For another $7000 you can get into the 120i grade, which lists for $46,990 and comes standard with the Urban Line package, which fits 17-inch alloy wheels in the double-spoke style, adds front and rear bumpers with matt finish air intakes, plus dual chrome tail pipes, while the cockpit gets leather upholstery, and gloss-black and pearl-effect trim.

Along with the Urban Line gear, the 120i has all of the 118i’s standard features and adds more of its own, including front and rear parking sensors, LED fog lights, dual-zone climate control, the interior lights package, plus smart phone connectivity with voice control.

The 125i is only a tempting $3000 above the 120i at $49,990 and it comes standard with the M Sport Package, which is what our most recent test car was fitted with (see the images of the orange 120i). The M Sport pack adds 18-inch light-alloy wheels and the tough body kit, the M Sport steering wheel and aluminium trim to the interior.

Apart from the M Sport package, also standard is an 8.8-inch screen with a DVD player and, somewhat disappointingly, cloth and Alcantara seats. Sure, they look nice, but how did the 120i get real leather and the 125i didn’t?

Still the 125i comes with more impressive performance hardware than the grades below, such as sports suspension, variable steering, M Sport brakes (inner vented rear discs) and blue calipers.

At the top of the 1 Series range is the M140i and while it’s getting into pricey territory at $59,990 (don’t forget that’s not including the on-road costs), you are getting what I’m predicting will be a sought after car in years to come. And possibly even a collector's item.

The M140i isn’t a fully fledged M car – it’s a diet version from the M Performance section of BMW, which gives cars a bit of a taste of the hardcore world of beasties like the M2 and M3, without costing as much or being quite as brutal to drive.

I’ll talk about the high-performance parts more in the sections on driving and engines, but briefly, you might like to know the M140 gets adaptive suspension and a six-cylinder turbo petrol engine – yes in a tiny hatch. Powerful.

The price is bang-on compared to rivals such as the new Mercedes-Benz A-Class and Audi A3

The M140i also has the standard features of the 125i and adds its own, such as the 18-inch alloy wheels, black chrome tail pipe, adaptive LED headlights, leather upholstery, keyless entry, power front seats and a Harmon/Kardon 12-speaker stereo.

So, is the 1 Series good value? The price is bang-on compared to rivals such as the new Mercedes-Benz A-Class and Audi A3 (click those to see my reviews of them, too), but the 1 Series gets less in standard features compared to the Benz (such as Apple CarPlay) and about the same level of equipment as the A3.

If you’re a fan of black and white, you might be relieved to know these are the only two colours you won’t have to pay for. The rest, including Sunset Orange (see the images), Seaside Blue, Melbourne Red, Glacial Silver and Mineral Grey cost $1190.

Both cars use versions of the three and four cylinder petrol engines from before, with the popularity of automatics leaving the previous manual option consigned to history.  The 118i’s 1.5-litre turbo three cylinder now produces 103kW/220Nm, with max torque available all the way from 1480-4200rpm. The 118i now uses the seven-speed dual clutch automatic transmission, as seen on Mini models that use the same engine. 

The M135i’s 2.0-litre turbo has been tweaked to take the place of the six-cylinder M140i from the last model and now produces 225kW/450Nm, with max torque available all the way from 1750-4500rpm. Its auto remains a torque converter though, but now the transverse-mounted unit also shared with Mini models with the same engine and splitting drive to all four wheels via the xDrive system for the first time. The drive split is constantly variable, but the rear bias tops out at 50 per cent and the only limited slip diff is an electric unit on the front axle.

As you step up through the grades the engines become more powerful. The entry-grade 118i has a 1.5-litre three-cylinder turbo-petrol making 100kW of power and 220Nm of torque, while its diesel twin has a 2.0-litre turbo-four making 110kW and much more torque at 320Nm.

The 120i has a 2.0-litre turbo-petrol four-cylinder and an output of 135kW and 270Nm. Then above that is the 125i, which is getting into performance territory with its 2.0-litre turbo four petrol making 165kW and 310Nm.

But all hail the M140i and its beautiful 3.0-litre six-cylinder turbo-petrol, with 250kW and 500Nm that it wants to share with you.

All cars are rear-wheel drive and all have an eight – hang on, that’s important: all cars are rear-wheel drive. Do you know how many other hatchbacks are rear-wheel drive? Try next to none – not the A-Class, not the A3, not the Golf. Rear-wheel drive is favoured for performance cars because it offers better balance and better acceleration thanks to the weight shift to the rear of the car. BMW has long claimed that RWD is one of the keys to its "sheer driving pleasure".

Now let me finish the sentence... all have an eight-speed automatic, and it’s a beauty – a little slow, but smoother for driving than a dual clutch, and way more fun than a CVT.

But wait, because there’s a manual gearbox, too. It’s a no-cost option and you can get it on any variant apart from the 125i.

Official combined fuel consumption is a decent 5.9L/100km with the 118i, but the M135i steps up to 7.5L/100km) 2.0 litre four in the m135i. Both engines require premium unleaded. 

Fuel tank sizes vary across the two models also, with the 118i measuring 42 litres and the M135i managing 50 litres, despite its need to package rear drive components somewhere under there also. 

This results in a decent theoretical range between fills of 711km for the 118i and 666km for the M135i. 

BMW says its most efficient petrol engine in the 1 Series range is the three-cylinder in the 118i, which uses just 5.2L/100km after a combination of urban and open roads.

The diesel unit in the 118d will use 4.2L/100km. Let that sink in for a moment – petrol engines are becoming so fuel efficient that they’re rivalling diesels, which have long been lauded for their frugality.

So don't just buy the diesel just because it’s more efficient, because you may never recoup the extra money you paid over the 118i.

Thirstier but still super-efficient is the 2.0-litre in the 120i. BMW’s claim is 5.9L/100km. During my week with the 120i I put 413km on the clock and used 15.57 litres doing so (measured at the pump), which comes to 7.7L/100km. The car’s computer said 7.8L/100km.

That’s great fuel economy, even if it is higher than the claimed figures. The 125i’s official fuel consumption is also 5.9L/100km.

It’s not surprising that the M140i, with its 3.0-litre six-cylinder turbo-petrol engine, is the least fuel efficient but its official figure of 7.1L/100km is still low.

For a brand with a marketing slogan of pure driving pleasure, this is the important part, particularly given the new 1 Series has lost its rear wheel drive USP. 

Why do some of us love rear wheel drive? It tends to be more fun when you're driving on the limit, and generally makes for nicer steering because you're only using the front wheels to turn corners.

So how does the new 1 Series drive? That depends on which version. 

The 118i is quite a nice package really. It rides a bit more gently than what I remember in the A-Class and generally feels more like a premium product. It also feels a step ahead of the 2 Series Active Tourer it shares its underpinnings with, which is a good thing.

The three-cylinder engine is quite smooth for a fundamentally unbalanced triple, and it makes enough power to get you out of trouble. 

Do you miss rear wheel drive? Not really, as you can only tell the difference when you're going real fast, which let's face it, is not somewhere 118i drivers are likely to go very often. 

The M135i is a vastly different beast, as you'd expect. Aside from being real quick, it's that much tighter everywhere, but still definitely on the more comfortable side than what we expect the future full house M version to be.

The continuously variable xDrive all-wheel drive system does a great job of putting its power down, but the rear bias maxes out at 50 per cent, which is probably spot on for chasing lap times, but means you miss out on the tailiness of the old one altogether. 

So it’s not as classically fun as the old M140i, but it’s easily faster, and that's what will probably matter most to most buyers. 

If I could run into a showroom and take whichever 1 Series I wanted it’d be the M140i – and not just because it would give me the best chance of outrunning the police after they discovered the break-in, but because the thing is so much fun to drive.

It’s also the most expensive, of course, but it’s worth it for that screaming straight six and for its agility.

You’ll have fun, though, in every grade of the line-up – they’re all engaging to pilot with great driving positions, good pedal feel and that eight-speed auto is smooth in traffic yet will shift hard when you have your race face on.

You might find the 118i, with its three-cylinder, a little under powered, especially with five people and their bags on board. If you’re keen on this grade, then consider the diesel, which will give you more torque. Our 120i test car proved to have enough oomph for overtaking and moving quickly when needed.

The 125i is less tame, with its throatier exhaust note, firmer ride and better handling thanks to the M suspension.

If you plan on choosing the M Sport Package for, say, the 120i keep in mind that you’ll lose the comfortable ride these cars have on their standard tyres.

Our 120i had the pack and while the body kit looks tough, the 18-inch alloy wheels shod in low-profile rubber (225/40 R18 Bridgestone Potenza 5001s front and 245/35 R18 at the rear) meant the ride was overly jarring on bad roads.

Given that Sydney was my test bed for the 120i and its roads are shocking, the ride was less than comfy. The M-sport suspension will only make the ride less comfortable, but in return you’ll have a 120i with better handling.

Run-flat tyres are common on BMWs and you may have heard of a few issues surrounding noise and a harsher ride. While that can be true, it's the price you pay for having a tyre you won’t immediately have to change if you get a puncture. Only the 120i and the M140i don’t have run-flats as standard.

The BMW 1 Series has the maximum five-star ANCAP rating, but this was awarded in 2011 and a lot has changed since then – particularly expected levels of safety.

BMW has updated the advanced technology to keep up with AEB (city) with pedestrian detection and lane-departure warning standard on all grades. It would be good to see more safety tech in the form of blind-spot warning, rear cross traffic alert and lane-keeping assistance.

For child seats you’ll find two ISOFIX mounts and three top tether points across the rear row.

A spare tyre is not something you will find – all apart from the 120i and the M140i have run flats, while those two have puncture-repair kits.

BMW is yet to step up to the five year warranty offered by most mainstream brands and now Mercedes-Benz and Genesis, continuing with the three year/unlimited coverage matched by Audi. 

As always, BMW describes the service intervals as condition based, and the car will alert the driver when a service is due. This will occur at least every 12 months though, but individual intervals will vary based on how the car is driven. 

This can all be bundled into five year/80,000km service packs though, with the Basic pack costing $1465, but the Plus pack adds brake pad and disc replacement to regular fluids and consumables for $3790. Assuming 12 month intervals, these prices are about average for a premium branded product. 

The 1 Series is covered by BMW’s three-year/unlimited kilometre warranty. Servicing is condition-based – the car will let you know when it needs a check-up.

BMW offers two service packages, which cover the car for five years/80,000km: the Basic is $1340 and the Plus costs $3550.