We have always delved into "serious" subjects, so here is something with a little bit more fun. The engine is the heart of the motorcycle; it is a fact no one could disagree with. But there were engines and then there were iconic engines.
It is those iconic powerplants that turn certain motorcycles into icons. In fact, a few of these engines went to influence those that came along years after their introductions, opening up entire spectrum of performance and production platform for the future.
Here they are, sorted by the year.
1. Honda Cub (1958)
Abuse it, neglect it, run it on kerosene, lubricate with cooking oil, the Honda Cub engine never seem to break. The pushrod, single-cylinder engine’s lineage can be traced all the way back to the original Super Cub in 1958.
You could still find examples of it or its successors dominating the streets of our South East Asian neighbours. The fuel-injected version is still being sold in Japan. It was the bike which introduced the semi-auto gearbox (shifting without a clutch lever or pedal) and teaches many about riding.
That solid reliability was more important than the 7 bhp and 6.5 Nm it produced, as Honda has sold more than 60 million Honda Cubs and the proceeds were used to fund Honda’s racing efforts. It was simply the most successful vehicle of all time.
2. Kawasaki H1 500 (1969)
It is said that the Kawasaki H1 was dominated by its engine, everything else be damned.
The 498cc, air-cooled, two-stroke which was also known as Mach III was built primarily for the stoplight GP crazed US market and the overriding interest was power-to-weight ratio. This entailed building a powerful engine and stuffing it into the lightest chassis they could possibly make (water pipe-like tubes). Being a triple meant the use of a 120o crankshaft, translating to lightweight clutch and gearbox, too.
The H1 weighed in at only 174 kg dry and the engine produced 60 bhp at 8,000 RPM at a time when tyres were skinny and frames were flexible, but It screamed through the quarter mile at 13 seconds. Cycle World Magazine reported that it, “trounced any mass production motorcycle regardless of displacement.”
Once the tach swung above 5500 RPM, the bike gave a hard kick making it possibly the first production road legal motorcycle to wheelie uncontrollably. Scary, but that was part of the thrill.
It was this bike that put Kawasaki’s name firmly on the map as a performance motorcycle maker.
3. Honda CB750 (1969)
Much have been written and romanticized about the Honda CB750 and why not. Motorcycles would have been very different if not this engine.
Four-cylinder engines have been around for many years, but they powered primarily racebikes. So, it was a revolution when Honda unleashed the CB750 to the masses. Truth is, this 736cc inline-Four powerplant was not high tech by Honda’s own standards as it only had one overhead cam and did not rev into the stratosphere. However, with 67 hp at 8,000 RPM and 66.4 Nm, the bike hit 193 km/h, making it the fastest production bike at its debut.
The CB750 was hence called “the first superbike,” but it was not just about performance that made it so popular. The engine was smooth, quiet, did not leak and reliable. It had an electric starter, five-speed transmission and four exhaust tips to show off the number of cylinders.
While the chassis was simple as were most bikes of the era, it was this bike which introduced the disc brake to the mass market.
It had long been reputed that this was the motorcycle that firmly swept the British motorcycle industry aside, besides smashing Harley-Davidson’s dominance of the American market.
4. Kawasaki Z1 (1972)
Kawasaki and Honda were locked in an arms race to build the world’s fastest production bike throughout the 1970s.
Kawasaki had been developing their own 750cc inline-Four but were surprised by the Honda CB750 which was much more powerful in 1969. So, they shelved the release of their bike, went back to their shed (okay, factory) and enlarged the engine to 903cc under the codename, “New York Steak.”
The 903cc, DOHC, inline-Four while powered the Kawasaki Z1 introduced in 1972 and made 82 bhp which was 14 more than the SOHC CB750. That may not seem to a lot but consider that the bigger engine produced more midrange and peak torque (78.6 Nm) too.
As it stood, the Z1 was the fastest production motorcycle of its time and blew everything else away.
5. Harley-Davidson Evolution (1984)
In 1981, the grandson of Arthur Davidson, Willie G. Davidson and Vaughn Beals led a group of 13 Investors to buy the beleaguered Harley-Davidson brand back from the American Machine and Foundry (AMF) for $80 million.
Good news, right? Not really, not yet anyway.
Harley-Davidson had only the Shovelhead engine which was introduced way back in 1966 at that point. It had too much in common with its Knucklehead predecessor; its performance was meager at best and its reliability left much to be desired. Quality had suffered so much under AMF that there was legend that dealers had to stick sanitary pads under the crankcases of new bikes, to avoid oil from dripping onto their showroom floors.
So, the new management went to work on a new engine. Although they kept the traditional 45o V-Twin layout, the new engine got a thorough update.
The cylinders became aluminum, the combustion chambers were redesigned, flat-top pistons replaced domed ones, the conrods were made stronger, the lubrication system was updated and a new electronic ignition system was introduced. These changes, together with a few others gave the now 1304cc, air-cooled, pushrod, OHV engine 10% more power and 15% more torque (106 Nm). It was lighter, ran cooler and smoother, plus a whole lot more reliable.
The engine was called “Evolution.” It was the engine that saved Harley from oblivion.
6. Honda NSR500 (1984)
This manic engine would have been on top if it were a Top Ten Countdown, hands down.
It was in 1984 when the NSR500 was ridden the first time by Freddie Spencer who took the 500cc GP crown in 1983 on an NS500 triple. To reduce friction, Honda used only one crankshaft in the V-4 two-stroke, compared to Yamaha and Suzuki’s V-4s that had twin contra-rotating (they spin in the opposite direction of the rear tyre) cranks. The Honda put out 144 bhp, making the competition look like blunt tools in chest.
“Fast” Freddie destroyed the 500GP field in 1985 by winning 8 out of 12 rounds (it was also the same year he won the 250cc GP title).
Australian madman Wayne Gardner followed suit in 1987, by which time the V-4’s cylinder angle was spread from 90o to 112o to improve its breathing efficiency. Eddie Lawson made the jump from Yamaha to Honda and took the title back from Yamaha 1989 after Honda fixed the evil handling chassis in order to cope with more than 160 bhp.
The Honda NSR500 continued to rule the roost into the 90’s with Mick Doohan winning five titles. His teammate Alex Creville also won a title. During that time, Honda turned the fierce V-4 into a “big-bang” engine by firing all cylinders in rapid succession in a bid to increase rear tire grip but Doohan reverted to the old “screamer” motor (fired its cylinders at 90o intervals) when the newcomers started challenging his reign.
Valentine Rossi moved up to the 500 GP class in 2000 and was surprised by the NSR500’s power, which was rumored to be close to 200 bhp. It took one more year for “The Doctor” to capture the title in 2001 with a detuned engine.
In total, the NSR500 won 130 GP races and 10 world titles in 18 years.
7. Ducati 851 (1988)
The father of the Desmodromic V-Twin, Fabio Taglioni, firmly resisted the idea of creating a four-valve head for the engine and left the project to Massimo Bordi.
Bordi had designed a four-valve Desmo engine as his thesis while studying engineering at the Bologna University to develop a new cylinder head design, in collaboration with specialist engine builders Cosworth.
The new 851cc, liquid-cooled, SOHC, 90o V-Twin engine made 95 bhp @ 9,000 RPM and 85.4 Nm @ 7,500 had a strong midrange that made riding effortless. Entered in the fledgling World Superbike Championship, Raymond Roche won the first of Ducati’s many WSB titles in 1990 on the 851 racebike.
The engine was soon enlarged to 888cc, then again to the legendary 916cc. The capacity kept increasing while gaining the Testastretta head update, until the Panigale 1299R Final Edition which signals the end of the 90o Desmodromic V-Twin for Ducati’s superbikes. But the engines which were derived from Bordi’s 851 still soldier on in Monsters, Diavels, and Multistradas.
8. Yamaha R1 (1998)
Yamaha’s FZR750 superbike was soundly trounced by Honda CBR900RR Fireblade in 1992. They had to respond but debuted the unpopular YZF1000R Thunderace in 1996, instead.
The real answer came in 1998 with the shark-like YZF-R1. There were three things the Yamaha R1 was famous for: weight, power, wheelbase.
The 998cc, DOHC, 20-valve, inline-Four powerplant produced 150 bhp and 97.6 Nm, trumping the now Honda CBR919RR which made only 123 bhp. The revolution in engineering design was the “stacked” transmission.
Instead of leaving it below and behind the engine, Yamaha’s engineers moved the transmission to just behind the engine, making the whole unit more compact. This compactness contributes to less weight and a longer swingarm could be used for more stability without compromising the overall wheelbase. This solution was so effective that virtually every manufacturer copied this design since.
Additionally, the cylinder and crankcase were cast as one piece and are thereby making the engine more rigid as a stressed member, in turn allowing the frame to build lighter.
9. Triumph Daytona 675 (2006)
When Triumph Motorcycles Ltd. was launched in the early 90’s, they had started out with 750cc and 900cc triple-cylinder bikes and 1000cc and 1200cc four-cylinder bikes. Triumph had tried cracking the 600cc middleweight class in 1997 with the TT600 but it was never as successful as the company hoped since it was swamped by the Japanese entrants.
The breakthrough came when Triumph launched the Daytona 675 in 2006. The new triple not only produced a healthy 125 bhp and 69 Nm, but it also had an abundance of midrange torque. The engine was then wrapped with a superb chassis and great-looking design. However, it was the character of the engine which won the bike accolades the world over.
When the bodywork came off, the Daytona became the equally – if not more – entertaining Street Triple naked sportbike/street fighter, which went on to become one of the best-selling motorcycle for Triumph. The Street Triple design as well as the 675cc inline-Triple went through a few revisions before it finally became the current 765cc iteration. That is not all, as the race-kitted 765cc engine went on to power Moto2 bikes beginning 2019.
The 675 also gave birth to the 800cc inline-Triple in the hot-selling Tiger dual-purpose bikes.
10. Ducati Panigale V4 (2018)
Although Ducati’s V-Twins have once dominated superbike racing (13 titles), the format has hit its performance ceiling within the superbike rules. The Panigale 1199 had won a number of races during its long campaign but have not won Ducati a single title.
The obvious step would be to increase the number of cylinders to the V-Four format used by the Desmosedici GP bikes.
The new (street-going) Desmosedici Stradale V4 displaces 1103cc, producing 214 hp @ 13,000 RPM and 91.5 lb. ft. of torque @ 10,000 RPM. With a race kit in which includes a full Akrapovic exhaust system, power if bumped up to 226 hp.
While that power rating may seem as if the Panigale V4 is a beast to ride, Ducati’s concerns were to produce a fast bike that is easy to ride fast, and it starts with the engine.
The engine features a whole host of innovations lifted from Ducati’s MotoGP experience, including the counter-rotating crankshaft to partly compensate for the centrifugal forces of the wheels. The bike is hence more agile while also lower the front end during acceleration while lifting the rear when braking to reduce power wheelies off corners.
Apart from that, as what Ducati calls the “Twin Pulse” firing order, the crankpins are offset by 70o as with the GP bike, in order to fire all four cylinders in close succession while leaving the rest of the crankshaft rotation unmolested by combustion pressure. The pair of cylinders on the left side fire first, followed by the pair on the right. This has the effect of making the bike sound like a V-Twin rather than a traditional V-Four.
The entire package was made as compact as possible and is only 10mm wider than the V-Twin. Consequently, Ducati was able create a new aluminum “forward frame” for the Panigale V4 which resembles a short aluminum twin beam frame, thus forgoing the Panigale’s usual monocoque frameless design. It is this type of frame that seeks to return front end feedback to riders. Additionally, a longer swingarm could be fitted while retaining the overall short wheelbase. A longer swingarm has the effect of straightline and braking stability, besides being able to hold the chosen cornering line while power is added on.
It may be premature to include this engine in this list (it has not won a WSBK title yet), but the Desmosedici Stradale V4 is a technological wonder that is difficult to dismiss.