BMW have started taking deposits for their upcoming R18 model, despite not having unveiled the finished bike or announced a price.
We’ve seen the R18 and R18/2 concepts, both of which suggest a classic cruiser look, and it would be a real shock if the Bavarian brand strayed too far from these, stylistically.
Details of the bike’s enormous 1800cc boxer twin engine were confirmed in late 2019, and it uses old-school tech like air-cooling and pushrod valve actuation, further supporting the expected classic style of the bike.
If you’re interested, you can register on the BMW website now.
Old tech punches clever on 1800cc air-cooled BMW R18 boxer concept
First published: 29 November 2019 by Ben Purvis
BMW’s forthcoming R18 cruiser range is one of the biggest motorcycling moves that the German giant have made in years but despite it being developed from a clean sheet they have turned to very traditional technology: air-cooling and pushrods.
Such old-school design is thrown into even sharper relief by the fact that in Milan, where BMW previewed the new bike, we saw two stalwarts of the cruiser world – Harley and Indian – displaying new water-cooled, overhead-cam engines. So what’s going on and how can BMW hope to meet emissions limits?
The answer revolves around BMW’s priority for the new engine: torque. Lots of low-end torque is key to a big cruiser engine and for that, capacity is king. Back in 2004 when the old R1200C was cancelled, BMW Motorrad’s then-boss, Dr Herbert Diess, put the blame firmly on the fact that its 1170cc engine was just too small.
The problem is that a big capacity and a long stroke, needed for low-revving torque, mean that the bike’s cylinders will inevitably be long. No problem on a V-twin but on a boxer engine like the R18’s it’s an issue; if the cylinders stick out too far the bike won’t corner or be able to squeeze through traffic.
Pushrod valve-gear comes to the rescue here. While a cam-in-block, pushrod engine lacks high-revving ability, that’s not what BMW are after. BMW need small cylinder heads to keep the engine’s width down, and that’s what pushrods provide.
The low-rev design means emissions aren’t the problem they might seem, either. High-revving engines need lots of valve overlap, when both the intake and exhaust valves are open at the same time, to get gasses through fast enough at peak revs.
But at low speeds that means there’s an opportunity for unburned fuel to get into the exhaust. BMW’s engine won’t need such extreme valve timing, so sidesteps that problem.
What about the air-cooling? The R18/2 had a key change compared to the earlier R18 concept in the form of an oil-cooler. Spy shots of the production version show an even larger one. So BMW are using oil-cooling to get back some of that temperature control while retaining the aesthetic advantages of air cooling.
Noise is another issue, but while air-cooled bikes lack a water jacket to muffle noise, the pushrod design makes up for that. With the camshaft and lifters burried in the block, they won’t be heard chattering like those in an OHC motor.
All in, BMW’s 'old-fashioned' R18 isn’t so much a throwback as a clever application of the right technology for the task.
BMW R18 concept explored:
- Cylinder heads No overhead camshafts means heads are more compact, allowing more capacity for less width.
- Pushrods Cam-in-block engine design means heavier, less rigid valve-train but it’s fine for low revs and mechanically quiet for Euro5.
- Long stroke BMW’s low-revving, long-stroke engine won’t need extreme valve overlap, making it easier to pass emissions tests.
- Oil cooler Carefully-designed oil system means engine hot-spots can be kept cool with oil, again helping with emissions control.
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Latest BMW R18/2 concept aims squarely at American cruiser market
First published: 05 November 2019 by Andy Calton
BMW have created a 'rough-around-the-edges' version of its custom cruiser Concept R18 using its bumper 1800cc boxer engine.
While we were hoping to see a production-ready performance cruiser, this is yet another toe being dipped in the Harley and Indian-infested waters.
BMW first revealed a stripped-back, raked-out version of this bike in May (see below), but have now given it a complete overhaul and called it the Concept R18/2.
This version seems squarely aimed at the sportier American cruisers from Harley-Davidson and Indian, as BMW bids to muscle in on the hugely lucrative State-side market.
It has striking wheels; 19in at the front and 16in at the rear to create a dynamic dragster look. The candy red paintscheme from the fairing to tailpiece is eye-catching and the teardrop tank certainly gives it plenty of drama.
The star of the show remains the twin cylinder boxer 1800cc air-to-oil-cooled engine and it’s in full view on this version. The shaft drive also helps keep the lines clean, which was an important part of BMW’s bid to create what they are calling a 'modern custom'.
This is now the fourth incarnation of the bike using BMW’s big boxer engine. As well as the two BMW offerings, Japanese custom house Works Zon created the Departed and Revival Cycles in America showcased the Revival Birdcage.
Although BMW won’t be drawn on further details of what a production version of this big-capacity cruiser will look like, it seems a matter of when, not if. At some point BMW must surely stop testing the water and simply dive in?
In-depth: BMW's R18 concept bike
First published: 18 July 2019 by Jordan Gibbons
BMW shocked the world when they unveiled the R18 concept recently – a softail cruiser with the largest capacity motorcycle engine the Bavarians have ever built – because it was nothing like any bike they’ve produced in recent memory. But the idea has been brewing in the background for quite some time.
"You know we’ve always had the idea of entering the American cruiser segment," Karl Victor Schaller, Head of Engineering at BMW Motorrad, told MCN. "So the questions were ‘can we do it with the existing 1200 engine [from the R nineT]?’ and ‘what is the possibility to extend that engine?’ because there’s always a little bit of headroom in each engine."
Following investigation BMW realised they could perhaps take the engine out to a 1350 but, to compete with the big twins from Harley-Davidson and Indian, they knew they needed more.
"Then we thought well maybe we do a little like in the past like the very old concept R5 with a supercharger," Schaller added. "So we said maybe a 1350 with a compressor would fit and the marketing guys said ‘that’s much better’ but it’s still not an 1800.
"Half the volume for a bike like this is in the States and they’re not talking about horsepower, they are talking about cubic inches. After we settled on 1800 we decided we need to do a whole new engine. You might think it’s not complicated because we have lots of boxer engine history but designing a boxer engine of that displacement is not very easy."
The R18 also presented a production departure from the brand that normally takes an engine-first approach to design – they are called Bavarian Motor Works after all.
"Normally engineering takes the lead and creates a new set-up for the GS," said Schaller. "In this case the designers took the lead and we tried to fit the technology into the design idea. In this segment it’s all about styling – no one cares about power. We started with the looks and tried to make engineering parts fit. The real bike you will see is not very far away from the concept."
Even so, the engineers didn’t have an easy time of it, especially with the new Euro5 rules waiting around the corner which stipulate the mechanical noise of the engine.
"We don’t have Euro5B, so the noise we can still control. We are expecting about a 2dBreduction which can be done with an engine like this, but if it’s more we’ll have completely different motorbikes. It’s not only the big ones – every bike would be affected. If we see 5, 6 or more dB reduction in engine noise, it would change motorbikes completely as you would not have any open engines any more."
Although performance details about the new engine are still thin on the ground, we do know it’s an air-cooled 1800cc boxer twin - not words that the chaps in white coats who draft emissions rules like to hear. Mercifully, BMW have come up with a solution that will see air-cooled engines sticking around for a little bit longer yet.
"The injector nozzles will move to the cylinder head, so they are no longer in the throttle butterfly body," revealed Schaller. "It’s still a port injection but it’s a completely different position. You’ll see this on all the models, we’ll move the injector nozzle closer to the valves."
The other issue is the sheer size of the pistons. Such a large capacity twin creates issues with the pressure and movement of engine oil in the crankcases.
"Oil control and oil foam control is not easy but we have a lot of experience with that, so we know what to do. This is maybe the biggest challenge on the engine."
BMW have already announced that a range of bikes with the new engine will be revealed later in the year and we’re expecting at least two distinct models – a softail and a full size bagger. As for the prices? We’d expect them to hover a few thousand each side of £20,000.
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BMW’s new super-cool concept is a sign of things to come
First published: 24 May 2019 by Jordan Gibbons
BMW have unveiled an all-new, stylish classic cruiser that looks set to take on Harley-Davidson in the near future. The R18 concept bike is a radical machine and shows that BMW are keen to woo cruiser and custom bike buyers.
Stripped down and raked out, the Concept R18 is not only a statement of BMW’s intentions, but also what their designers and engineers are capable of. From the total lack of switchgear, to the fishtail exhausts every single detail of the bike has been meticulously considered.
"This bike is not about being the fastest," says Edgar Heinrich, BMW Motorrad Head of Design. "This bike is about making an analogue statement in a digital age. BMW has a rich history of iconic motorcycles and they bear the same design characteristics. We believe that this can still work well today, together with current technology.
This isn’t the first time we’ve seen the R18 engine – BMW gave one to Custom Works Zon and another to Revival Cycles to get their take on it – but it’s the first time we’ve seen anything from the mothership.
BMW say that this bike is a tribute to the original 1936 R5 (below) and more recent R5 Concepts, but with a bit more meat in the engine department. The 21in (front) and 18in (rear) wheels give it a classic stance and the much-loved leaf-shaped saddle looks like it’s come straight of a 1950s Beemer.
The rest of the bike is dripping with stylish touches such as polished head covers, subtle shading and the teardrop tank. Even the pinstriping and Metzeler Rille tyres give it that cool custom vibe. Then there’s the completely open shaft drive, cantilever suspension, open carbs and a tiny LED light nestled between the fork legs. Even if you don’t like the style, you can appreciate the workmanship.
BMW have admitted that they are planning a whole range of cruisers later this year. Until now BMW’s heritage range has made do with engines from existing models, so to create a whole new engine platform for one bike seems unlikely.
We’ve already seen spy pics of a big bagger but it’s possible BMW will also present smaller, stripped-back bikes to compete with Harley-Davidson’s ever-popular Softail range as well as the likes of the Triumph Bobber.
BMW have said they will unveil the production bikes later this year, most likely at the EICMA motorcycle show in November but if this tantalising taste of what’s to come bears any resemblance to the finished articles, we’re going to be in for a treat...
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