From V-twin to inline-four, behind every great bike is a great powerplant, but which of the best 2016 units truly stirs the emotions?
They define the character of our bikes far more than the styling, and many riders never stray once they’ve found their favourite configuration. But which is best? We pitch inline-four, V-twin, parallel-twin, V4, inline-triple and single cylinder bikes against each other to see what really works best on the A and B-roads of biking Britain.
We are truly living in a blessed time when to comes to two-wheeled development. Gone are any signs of the ‘Universal Japanese Motorcycle’, now every manufacturer is striving to stand out from the crowd. And what better way to achieve this than to have its own signature engine?
On a motorcycle, the engine provides far more than just power. This lump of animated metal contains the bike’s heart and soul and, in terms of showroom pulling power, can be a stronger draw than the rest of the bike’s technology put together. Some riders fall in love with the feel of a specific motor and base their entire buying decision on that single emotion. Others refuse to step outside their comfort zone and fail to experience the variations on offer.
So what is it that makes an engine truly great? Is it a vibration, the number of cylinders, or simply a sound? Can a single cylinder evoke the same pleasure as a inline-four? MCN brought together six of 2016’s best engines - the Aprilia Tuono’s V4 1100, the BMW S1000XR’S 999cc inline four, the 675cc triple from the Triumph Daytona, Ducati’s Monster 1200 R’s L-twin, Yamaha’s crossplane-cranked MT-10 and KTM’S 690 Duke single - to discover which is the greatest of them all.
THE SINGLE KTM 690 DUKE
There was a time when big singles vibrated like jackhammers, earning them the nickname ‘thumpers’. With its latest generation of LC4 motor, KTM has totally dispelled this perception. This is a large-capacity single that is smooth and allows all of the engine’s many plus points to shine through rather than being hidden behind an irritating wall of vibration.
Singles are never going to be everyone’s cup of tea due to the fact that they will always be limited in their performance, and despite the fact the Duke’s is the most advanced motor of its kind ever built, it still only makes 72bhp. But headline power figures don’t tell you the whole story…
When it comes to performance, power and weight are inextricably linked and the more the weight drops, the more power the bike appears to have. And that’s the key to KTM’S single.
Despite its modest power, the Duke feels far more spirited thanks to the fact that it tips the scales at just 148kg. And that’s what shows up in the ride.
Compared to the other bikes, the Duke feels like a toy. With only one cylinder inside its frame, the Duke is extremely compact while its lightness gives it real agility. The single-cylinder motor punches its power out with a lovely instant throttle response and an exhaust note that is pleasingly brash and unashamed. While the rev limiter does chime in with annoying regularity, that’s simply down to the fact a single can’t handle as many revs as a multi-cylinder engine and this trait adds to its charm. If you want to feel like you are working a motor and enjoy keeping something on the boil while whipping through both the gears and bends, then a single will certainly appeal and the LC4 is the best of the bunch. Best for: Light weight and a delivery that smacks like a solid punch Worst for: Outright power and top-end performance
THE INLINE FOUR BMW S1000XR
Over the years the inline-four has dominated the sportsbike market thanks to its ability to make huge power figures with seeming ease. Yet it hasn’t been until recently that it has started to stray away from sports or naked bikes and instead moved into the likes of adventure-style machines such as the XR or Versys. Do an inline-four’s engine characteristics lend themselves to this new role in life? I’m not convinced.
Make no mistake, the inline-four engine is probably the greatest configu- ration ever developed. It has allowed road bikes to produce power figures touching 200bhp with total reliability, which is a staggering achievement, but it has its drawbacks. As a sportsbike rider you need to love feeding your bike revs as that’s how you get power from the configuration, but that’s also one of its disadvantages. No matter how much re-tuning you give an inline four, they always feel like they want you to rev them harder and faster, making them less relaxed than the likes of a twin. These are motors that love to be worked which suits their role within the frame spars of sportsbikes but isn’t so ideal on a more relaxed tourer, as the BMW S1000XR demonstrates.
On a constant throttle the XR seems to be straining to go faster while the engine buzzes and the exhaust note howls
‘If you want to feel like you are working a motor, a single will certainly appeal’
‘More than just power, this lump of animated metal contains the bike’s heart and soul’
– another inline-four disadvantage.
This engine format has the most aurally grating exhaust note of any engine configuration. Fit loud pipes to a twin or V4 and people generally appreciate the extra volume, do the same to an inline and its high-pitched wail only irritates. What do you hear breaking the silence of the countryside at weekends? It’s not the drone of a V-twin...
Yet despite its disadvantages, in many ways the inline-four still rules the engine roost. It’s cheap to manufacture, simple to tune, reliable, generally lacks vibration and can have its power delivery tailored with relative ease. But compared to a V4 or soulful V-twin, it does lack a degree of character.
Best for: Accessible performance Worst for: Character and feel
THE V-TWIN DUCATI MONSTER 1200R
No other exhaust note epitomises the sound of racetracks in the 1990s than the flat drone of a V-twin – or an ‘L-twin’ if you’re a Ducati owner. It’s a noise that makes the hairs on the back of your neck stand up, and when you are revving a V-twin hard it’s easy to be transported back to Brands Hatch WSB, standing on the banks in a sea of red.
This style of engine splits opinions and when you ride a modern V-twin you can see why. On a constant throttle the motor is nice and smooth, but ask it to accelerate and its character changes and you can almost feel the two huge pistons thrashing up and down in the cylinders. V-twins aren’t smooth like inline-fours, they vibrate and rattle when asked to work hard, yet the power output isn’t as engaging as on other motors.
You never feel like you are rushing on a V-twin as the monotone exhaust and flat torque delivery are deceivingly fast. These aren’t motors that deliver the instant hit of thrills that you get with a fast-revving V4 or inline-four, instead they hide their true potency behind a wall of smooth drive.
Many riders were put off V-twins due to some horrific early fuel-injected models making their throttle response snatchy and aggressive. Modern fuel systems have removed much of this feeling, but simply down to the momentum required to shift the massive pistons V-twins are never going to be perfect. Let the revs drop too low and they shudder and protest, while fail to pay attention to the tacho and the rev limiter rushes in seemingly from nowhere. But if you want to go fast with minimal effort, no motor does it better than a V-twin. Best for: Lazy riding, mid-range drive, character Worst for: Initial throttle feel
THE V4 APRILIA TUONO V4 1100 FACTORY
From the moment you first open the throttle the Tuono’s engine feels light and fast to rev, picking up speed with enough ferocity that the traction control warning light is continuously flashing as the electronics struggle
to keep it all under control. It’s not a relaxed ride, and is accompanied by a symphony of mechanical clatters and rattles from deep within the engine that only heightens the raw nature of the experience.
From the mighty 500GP two strokes to the latest RCVS and even the legendary RC30 and RC45, the V4 engine has long history of track success and Aprilia’s own V4 has taken three WSB titles. What makes it so successful? The V4’s architecture lends itself to track riding and Aprilia have tailored their version to not only drive out of bends with typical V4 thrust, but to also have a searing top-end rush thanks to lightened engine internals. But it doesn’t have to be this way.
Other V4s such as Honda’s VFR range demonstrate the flexibility of this style of motor by delivering a far more relaxed ride that concentrates on midrange and fluidity of drive. But when it comes to showcasing the sheer speed and aggression possible from a thoroughbred V4, the Tuono 1100 knocks the practical VFRS out of the water. If you want an engine to thrill, and also sometimes scare, you need look no further than Aprilia’s V4. Best for: Mind-bending performance Worst for: Disconcerting aggression
THE ODDBALL YAMAHA MT-10
Yamaha’s CP4 crossplane crank engine is a real Marmite motor as initially it disappoints, but once you spend a bit of time with one, it will change your whole perception on inline fours. Or you will hate it and wish it had a conventional firing order…
While Yamaha will bang on about inertial torque and the benefits the crossplane has when it comes to drive out of bends, to road riders this doesn’t matter one iota. What the crossplane offers to road riders is a truly different riding experience and one that injects a real dose of character that is lacking in a conventional across-the-frame four.
When you are on a constant throttle the CP4 engine is totally inert and lacking any kind of vibration or quirks, however give it some gas and its whole character changes. The smoothness vanishes and the motor develops a lumpy feeling in a similar fashion to a twin as it picks up revs. It doesn’t
‘If you want to go fast with minimal effort, no motor does it better than a V-twin’
scream towards the red line like a conventional four, but again like a twin it builds momentum deceptively quick while punching forward and delivering a wonderful off-beat exhaust note. It’s a unique feeling in the motorcycle world and one that either wins it friends or enemies depending on what riders seek in an engine.
Doubters detest the lumpiness of the motor under power, fans enjoy the V-twin grunt without the traditional stuttering caused by the twin-cylinder configuration at lower revs. But when you look at Yamaha’s YZR-M1 race bikes, it’s hard to argue against its effectiveness. Best for: Character and performance combined Worst for: Instant gratification, and roughness during low to mid-range hard acceleration
THE TRIPLE TRIUMPH DAYTONA 675R
Within a few seconds of pulling away on the Daytona 675R one question is rattling around in my head ‘why on earth does everyone forget about this bike?’ The Daytona is a simply beautiful to ride and it is all down to one factor – its inline-triple engine.
When Triumph first unleashed their small capacity triple in 2006 it caught everyone by surprise and to this day it remains a revelation. I can’t think of another engine that delivers such a thrilling and enjoyable ride with so few, if any, irritations. It’s a brilliant motor and that’s why both Yamaha and MV Agusta have followed suit and developed their own versions of the format. Although neither have matched Triumph’s near-perfect execution.
It’s very hard to put a finger on what makes the 675 triple so pleasurable to ride. The rasping exhaust note certainly plays its part. Then there is the useable midrange, which is so much more than you would expect from ‘just’ 675cc. It could be the kick of top-end drive, which is injected precisely when the mid-range starts to dip, or even the bike’s lightness and agility. But in truth it’s a combination of all these factors.
The thing that makes the 675 triple so special is the balance that Triumph have engineered into the motor. As well as a beautiful throttle response, it is the way that every aspect of the engine works together seamlessly to enhance the ride that makes it so spellbindingly good. There isn’t the feeling of the drive overpowering you as there is on the Aprilia V4, it’s engaging unlike the BMW’S inline four, it has a similar off-beat crossplane feel as the Yamaha and even the lightness of KTM’S single. The Triumph triple is the best of all worlds and aside from slightly lacking in ultimate top-end power, it’s incredibly hard to fault. What a motor. Best for: Combining midrange and top-end power effortlessly Worst for: Big power
BMW’S mighty inline four loves to rev but is a little buzzy for a tourer
Revvy, gutsy, light and agile, the Daytona 675 is the perfect sportsbike
KTM 690 Duke is a single-minded fun machine
Oddball looks combine with an oddball engine
The Monster’s roar has always been created by a Ducati L-twin
Blistering out of bends, the Tuono’s V4 shove will thrust you at the horizon
A V4 layout allows for bikes like the Aprilia to be very slim
Grooving to a different beat, crossplane MT-10 sounds like Rossi’s bike
Naked MT-10’S inline four has an uneven firing order
Itõs a triumph of engineering, the Daytonaõs 675cc triple is the perfect balance