Every now and then I see a little argument on some forum about what an “inline twin” is and how it’s different to a “parallel twin”. Hearsay flies around and people make guesses. (I discuss this below.)

But what’s often really misunderstood is the 270-degree crankshaft. What does it mean? Again, people often pass on what they’ve heard, or what marketing people have told them. The truth lies somewhere in between.

In this guide I’m going to go over:

  • What is a 270-degree crankshaft parallel twin?
  • Why use a 270-degree crank — and not a 360-degree crank, a 180-degree crank, or a V-twin?
  • What are all the motorcycles that have a 270-degree crankshaft in a parallel twin format?

Enjoy!

Are you obsessed with motorcycles?

Well, I am. That’s why I created this site — as an outlet. I love learning and sharing what others might find useful. If you like what you read here, and you’re a fraction as obsessed as I am, you might like to know when I’ve published more. (Check the latest for an idea of what you’ll see.)

What is a 270-degree crankshaft parallel twin?

Firstly, a parallel-twin engine includes (nearly*) any engine with two cylinders in which they share one cylinder head. See two exhaust pipes? You have found yourself a parallel twin!

Suzuki V-Strom 800DE Engine Parallel Twin
Suzuki’s Parallel Twin in the V-Strom 800

* Reader Matt Carmichael commented that some motorcycles may have twin ported heads, like in the case of the single-cylinder Honda XBR500, which still has two exhaust headers.

There’s no difference between an “inline two-cylinder engine” and a “parallel-twin engine”. Or various other names I’ve heard that sound silly.

Parallel twins come in various kinds of firing order. There’s the 360-degree crank, where the pistons take even turns to fire, and the 180 and 270-degree cranks, where things are less even but more interesting.

To go over these, let’s quickly review how the four-stroke engine works.

Four-stroke engines (which make up the lion’s share of the market) have four distinct strokes (surprise!) of the piston. There’s:

  1. Intake — sucking in the air/fuel mixture into the cylinder as the piston goes down
  2. Compression — squeezing the mixture into a compressed area, before it’s blown up by the spark
  3. Combustion — the spark plug makes it go bang! driving the piston downwards, and
  4. Exhaust — the piston goes back up, sending the exhaust fumes out, before sucking in more fuel.

So in a single-cylinder engine, the engine rotates twice for every time the cylinder fires.

But what about in a twin? They don’t just fire at the same time, surely? Well, they could (but they usually don’t).

The 360-degree crank

The easiest configuration to understand of a two-cylinder engine is the 360-degree firing order.

Triumph Bonneville with 360-degree crank
Triumph Bonneville parallel twin

In 360-degree firing order in a parallel twin, both pistons move up and down at the same time. So when moving up, one is compressing, while the other is doing exhaust; when moving down, one is doing combustion, while the other is doing intake. They take turns this way.

The main advantages of 360-degree systems are that a) they run more smoothly than a single-cylinder engine, and b) you can use just one firing system (coil).

So in a 360-degree firing order, if every letter or number is 90 degrees, firing is like this: Bang, 2, 3, 4, Bang, 6, 7, 8.

The 180-degree crank

In a 180-degree firing system, the cylinders move in opposite directions.

This means that when one is going up, one’s going down. Piston one combusts as the second does compression, then piston two combusts (a half-revolution after piston one did) while piston one exhausts. That half revolution is the so-called “180-degree” difference after which this configuration is named. Both pistons now have to go through exhaust, intake, and compression again — 540 degrees before the next.

So the firing order for a 180-degree firing system is like this: Bang, 2, Bang, 4, 5, 6, 7, 8.

The advantage of a 180-degree firing system is that it has balance. The pistons move against each other.

One effect of a 180-degree firing order is that you get a “rocking couple” effect. It’s like when you’re rowing — when you row on the left, then on the right, the boat rocks right to left. You feel this as vibration in a motorcycle. In a modern parallel twin, like in the Kawasaki Ninja 650, the engineers counter with a counterbalance shaft. This reduces vibration, but never eliminates it.

So on a 180-degree crank engine, you do have to use a balance shaft to reduce vibration, but it results in a lot more smoothness than a single or even a 360-degree engine.

The only complaint people have of a nicely balanced 180-degree parallel twin is that they tend to sound a little “boring”. This is partly a function of the bikes you find them in — mildly tuned commuter bikes like small-displacement Japanese bikes. But they certainly can sound fiery, as many owners of older Bonnevilles who’ve cut off the exhausts will tell you.

The 270-degree crank

In a 270-degree firing system, firing is in between what you get on 180-degree and 360-degree systems. The pistons move out of step, syncopated. One piston is three-quarters of a rotation behind the other. The firing system is Bang, 2, 3, Bang, 5, 6, 7, 8.

This is the same firing order as a 90-degree V-twin (which Ducati calls an L-twin), which is why the two engine types are often compared.

Here’s the firing order of these three engine types explained visually.

how 270-degree cranks, 180-degree cranks, and 360-degree cranks work
Illustration of the cycles of firing orders for different parallel twin crankshafts
animation of crankshaft and firing order for 270-degree crank
The 270-degree crank — one piston is always in motion

But why use a 270-degree crankshaft? Good question.

Why use a 270-degree crankshaft in a parallel twin?

The advantages of a 270-degree firing order are that basically, it’s somewhere in between 180 and 360.

Not joking! It has less primary balance than a 180-degree engine (bad), but less of a rocking couple (good). It has more balance than a 360-degree engine (good), but has more rocking couple (bad).

Firstly, the most interesting thing about a 270-degree crankshaft twin is that it there’s never a piston that’s not moving. Look at the above image again. In the 360 and 180-degree configurations, there’s always a point where a piston is either at TDC or BDC and thus has to start moving again in the opposite direction.

Yamaha calls the effect of an engine never stopping being “removing inertial torque”. They call it a feature of all their “crossplane concept” engines, starting with the inline 4 of the Yamaha R1 (from 2009 onward).

Secondly, a lot of customer research by companies (and also anecdotal evidence from riders) shows that the vibrations produced by a 270-degree configuration are really… pleasant. People enjoy the net effect of the slightly lumpy sound, even though you can make almost any engine sound interesting (and it’s quite subjective anyway).

According to Triumph engineers, they considered the aesthetics of the 270-degree engine, but also considered a couple of engineering advantages. There are vibrations that are caused by forces in engines of any kind. There are primary forces, that happen once per revolution, and secondary ones, that happen twice per revolution.

Engineers have to use counter-balancers to reduce engine vibrations. In most parallel twins (all modern ones) there are counter-balancers to get rid of vibrations.

These forces can produce vibrations if they are not balanced. Engineers use primary balance shafts to balance the primary forces and also the rocking couple that can be left if no balance shaft or only one balance shaft is used.

Now, to balance the secondary reciprocating forces. Except… in a 270-degree crank layout, there aren’t any. Secondary reciprocating forces cancel one another out. That’s the magic of always being in motion.

Finally, one question you might have is “So why not do all this, but in an L-twin, like Ducati?” For three reasons (that I can think of)

  1. A parallel twin is easier to cool. It’s hard to cool the rear cylinder in a Ducati, or any V-twin, particularly if they’re air-cooled.
  2. A parallel twin is lighter. There’s just one cylinder head.
  3. A parallel twin is easier to maintain. In most modern motorcycles, it means just one cylinder head; or at the very least, similar access to both.

Basically, in writing this I’m going to find it hard to ever buy a motorcycle again that’s not a parallel twin. (But I do have a thing for Ducatis…)

Motorcycles with Parallel Twin 270-degree crankshafts — a complete list

The reason I started this article was mostly that I wanted to create a list of motorcycles that have a 270-degree crank. What are all the bikes out there with character? Tell me! (I know about Norton…)

Here they are, in alphabetical order of brand.

Aprilia motorcycles with a parallel twin 270 Degree Crank — the 660 engines

Aprilia RS660 - sport motorcycle with a 270-degree crank

Aprilia has produced a ton of V-twins and V-fours, and they’re awesome. They’re pretty much all on my “to-ride” list.

But Aprilia surprised me by releasing the RS 660 for 2021, a motorbike with a parallel twin and a 270-degree crankshaft and definitely one of the most interesting new motorcycles of 2021.

There’s a lot of praise I’m ready to sing for the RS 660 — I love the reincarnation of a middleweight sportbike with a “not ridiculous” riding position, cruise control, and cornering ABS. And the crankshaft is just icing on a very delicious cake!

Other motorcycles from Aprilia with the same engine also have the same crankshaft — like the semi-naked Tuono 660, or the Tuareg 660 adventure bike.

Here’s a comprehensive overview of the differences between the Aprilia RS 660, Tuono 660, and Tuareg 660, which all share the same engine fundamentally (though in different states of tune).

Aprilia Tuareg 660 RHS outdoor static - EICMA runner up
Aprilia Tuareg 660 — with a 270-degree crankshaft engine

BMW motorcycles with parallel twin 270-degree cranks — The F 850 / F 750 engines, and the F 900 R and F 900 XR

BMW updated their F 800 GS and F 700 GS to the F 850 GS, and F 750 GS. Both of these bikes use the same 853 cc parallel twin — but the F 750 GS is in a milder state of tune.

BMW F 850 GS Static LHS
BMW F 850 GS

The previous generation F 800 GS (and other F 800 bikes) had a 360-degree crank, but BMW changed this to a 270 / 450 degree crank for the 850 / 750 line.

Then, in 2020, BMW updated their F 800 R to the F 900 R, and also released the adventure tourer F 900 XR.

BMW F900R and F900XR motorcycle with 270-degree crank parallel twin
An F 900 XR I took for a spin

The earlier BMW F 800 R (and ST and GT) had a more traditional 360-degree firing order engine, but the engine in the newly released 2020 F 900 R and F 900 XR engines is a livelier 270-degree crank motor.

The F900XR is the more adventure touring and slightly higher-spec version of the F 900 R (and would be my pick of the two in most markets).

CFMOTO Motorcycles with a 270-degree or 285/435-degree crank

CFMOTO has two engine classes with a 270-degree crankshaft: the 800 class, which has the KTM 799 cc LC8c motor, and the newer 450 class.

First the 800 class. The engine in these (shared by the KTM 790 Adventure / Duke) actually has a 285/435-degree crankshaft, but has a very similar feel and firing order to the 270-degree crank.

CFMOTO first released the 800MT (known as the Ibex 800 in the US) with this engine, but has since broadened out the line to the 800NK naked sport bike.

More recently, the CFMOTO 450 line’s engine has a 270-degree crankshaft too. This makes it a rare small-capacity engine with this style of firing order.

There’s the CFMOTO 450SS (known as the 450SR outside the US) sport bike, the 450NK naked, and the 450MT adventure touring motorcycle announced at EICMA 2023.

All these 450-class motorcycles are powered by a 451cc parallel twin with a 270-degree crank. They’re all tuned to make learner-legal power in markets where there are restrictions.

Honda motorcycles with parallel twin 270-degree cranks

Honda has produced a lot of engines in the past, but since the 80s it rarely has used a parallel twin — though some of its more unusual motorcycles have been V-twins.

The first recent Honda motorcycle that came to my mind was the Africa Twin CRF1000L, released in 2016. The Africa Twin has a 998cc parallel twin with a 270-degree crank.

Honda Africa Twin CRF1000L
Honda Africa Twin CRF1000L with a 270-degree parallel twin

The 2019+ Honda CRF1100L Africa Twin also has a 270-degree crank, and a rumoured Honda Africa Twin 850 would also probably have it.

Next, the 2020 Honda Rebel 1100 (one of the motorcycles that I thought of as my “next”) has the same engine as the CRF1100 Africa Twin — albeit in detuned form. And has the same 270-degree crank.

2021 Honda Rebel 1100 in black with a 270-degree parallel twin engine.
2021 Honda Rebel 1100 — another motorcycle with a large 270-degree parallel twin

In 2022, Honda released a third bike based on the same Africa Twin engine — the Honda NT1100 sport tourer. It also has a 270-degree crank, as you’d expect.

Aside from these three Africa Twin engine-based motorcycles, Honda has used a 270-degree crank in another series of engines — the much more sedate NC700 and NC750 “street bikes”. This extends even to the Honda X-Adv maxi scooter. Rumour has it that an upcoming NC850 will also have it.

Honda NC750 parallel twin with 270-degree crank
Honda NC750

The 2023 Honda CB750 Hornet also has an all-new 755 cc Unicam parallel twin with a 270-degree crank, as will the similarly-engined Honda XL750 Transalp.

KTM motorcycles with a 285/435-degree crank

KTM 890 Adventure R - 285/435 degree crank
KTM 890 Adventure R – 285/435 degree crank

KTM produces motorcycles with its LC8c parallel twin with a 285-degree crank. This isn’t quite 270 degrees, but it’s conceptually very similar and so deserves a mention. (The abovementioned CFMOTO 800MT also has the same engine, and thus the same firing order).

It started with the KTM 790 Duke and KTM 790 Adventure/R, but the 890 Duke/R and 890 Adventure/R have the same firing order, as done the 990 range.

The crank pins are offset by 75 degrees, which means that the sparks are separated either by 285 degrees or 435 degrees (360 +/- 75), depending on which one you start counting from (both pistons fire in each 720-degree cycle of the four-stroke engine).

The crankshaft angle is supposed to mimic the power delivery from KTM’s V-twin engines, which have a 75-degree angle.

2024 KTM 990 Duke studio rhs 3-4 orange
2024 KTM 990 Duke

Norton Commando 961

Norton Commando 961 Café Racer RHS 3-4 front studio image
Norton Commando 961 Café Racer

The Norton Commando 961 is powered by a 961 cc air/oil-cooled parallel twin engine with pushrods and two valves per cylinder. It may be an old-fashioned and relatively low-powered motorcycle, but it has a 270-degree crankshaft, keeping it in line with the times.

Royal Enfield — the 650 cc engines with 270-degree parallel twin engines

Royal Enfield introduced a 270-degree parallel twin in their Continental GT and their Interceptor 650.

Royal Enfield Interceptor 650 — parallel twin 650cc with a 270-degree crank

These motorcycles won’t wake the dead. In Australia, they’re learner-legal, which means they’re relatively slow. But dang, they look smart! And they pack ABS, an engine with copious character for the price, and all the power you need for quieter roads in a handsome and very affordable package. Could be the one for many.

Other Royal Enfield motorcycles based on the same parallel twin, like the Super Meteor 650, are based on the same motor and have the same 270-degree crankshaft configuration.

Royal Enfield Super Meteor 650 Black studio RHS hi res
Royal Enfield Super Meteor 650

Suzuki 270-degree Crank Motorcycles — The GSX-S8 and the V-Strom 800DE

For the 2023 model year, Suzuki released not one but just two motorcycles with parallel twins, something they didn’t have in their line-up. And for 2024, the fairing-equipped GSX-8R shares the same engine.

All these motorcycles are based on the same motor, a 776 DOHC parallel twin with a 270-degree crankshaft.

This is interesting because they’re quite different motorcycles — two are street/sport bikes that may take the place of the Suzuki SV650 (hopefully not!), and one’s an entrant into the rapidly growing middleweight adventure category.

Triumph Motorcycles with a 270-Degree Crank — Many, but it Started with the Scrambler

Triumph was also pretty early to the party with the 270-degree crank.

Traditionally, Triumph parallel twins had 360-degree cranks. These could sound pretty beastly… I’ve heard some raucous older Bonnevilles!

But for the 2006 Triumph Scrambler (see my buyer’s guide), Triumph took the same engine and decided to upgrade the experience with a 270-degree crankshaft.

Triumph Scrambler - carburetted ealier version with a 270-degree crankshaft
Early Triumph Scrambler 2006

Triumph soon added this configuration to the Speedmaster and the America, two “moderate”-sized cruisers, also keeping the configuration for the larger Speedmaster in 1200 configuration, plus other cruisers like the Thunderbird.

Triumph Thunderbird Commander Static RHS front 3-4
Triumph Thunderbird Commander

Since the 2016 rebrand of the Bonneville to the Street Twin (and the Scrambler to the Street Scrambler), all Triumph parallel twins have had a 270-degree crank. This extends to the more modern, bigger 1200cc motors — like the Speed Twin and the Scrambler 1200.

Yamaha motorcycles with parallel twin 270-degree crankshafts — CP2 engines, plus others

Yamaha was the first manufacturer to make popular a 270-degree crankshaft with the TRX850, first produced in 1995. What a stunning bike! Sure, it was trying to look (and sound) like a Ducati, with that trellis frame especially, but I don’t care because I love it. They’re in short supply now, and sellers know that they’re cool, unfortunately.

Yamaha TRX850 Studio blue RHS 3-4 studio crisp
Yamaha TRX850 Studio blue

Yamaha made a couple more parallel twin engines with 270-degree cranks, like the TDM850 and TDM900, but they haven’t been in production for a long time now. Still, they have a loyal legion of fans.

In recent times, Yamaha brought back the 270-degree crankshaft with their CP2 motor.

“CP” stands for “Crossplane”, which was a trademark they gave to the unusual firing order of the Yamaha R1 (see my buyers guide) that gives it that incredible sound.

Yamaha CP2 crossplane parallel twin engine with a 270-degree crank
Yamaha CP2 engine — 689cc parallel twin engine with a 270-degree crank

The Yamaha CP2 engine is a 689cc water-cooled 4-valve-per-cylinder parallel twin with a 270-degree crankshaft (hence the “crossplane concept” designation). The “crossplane” designation is a bit weird — mostly marketing — but the CP2 engine is one of the most-loved modern engines.

The MT-07 (previously known as the FZ-07 in some markets) is a wildly successful competitor to the Suzuki SV650. And yes, the MT-07 has that 689cc CP2 engine.

The XSR700, which shares the same engine as the MT-07, also benefits from the lively CP2 engine, as does the Ténéré 700, the Tracer 7 (Europe only), and the 2022 Yamaha YZF-R7.

2022 Yamaha YZF700 YZF-R7 best looking motorcycles - side view on track
2022 YZF-R7

One other interesting addition to the Yamaha list is the Yamaha Super Ténéré XTZ1200.

Yamaha Super Tenere XTZ1200Z LHS static outdoor 270-degree crankshaft
Yamaha Super Tenere XTZ1200Z

The Super Ténéré is a bit of an unsung hero next to all the other adventurers, but it’s a super-competent and reliable big adventurer that easily goes toe-to-toe with the likes of the BMW R 1200 GS (maybe an older gen as the Ténéré hasn’t been updated in a while). It has a 1199 cc liquid-cooled parallel twin with a 270-degree crankshaft, and puts power down via a shaft drive.

However, not many describe the big twin in the Super Ténéré as being “exciting” — so not all 270-degree twins are necessarily so.

Brands missing from this list

I think it’s more interesting to note the other big brands that are not on this list.

I may have missed a couple. But below are some of the motorcycle manufacturers that I know have not made parallel twins with 270-degree cranks.

  • Ducati — All L-twins or V-Fours (in modern history, although they’ve done parallel twins in the past). Given their forays into other engine architectures, I wouldn’t be surprised if they came out with one soon.
  • Kawasaki — They do have a lot of parallel twins. But the W800 for example has a 360-degree crank, and the Ninjas of various sizes have 180-degree cranks.
  • Moto Guzzi — They do all V-twins (mostly air-cooled, though some recent ones liquid-cooled), transversely mounted.

Have I got something wrong? I google a lot, but I miss things all the time. A visit to a motorcycle museum confirmed how much I just don’t know. If there’s a detail you want to correct me on, please do say hello and email me.

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45 Comments

  1. Nice article, which helped simplify my understanding of the 270 engine.I currently ride a 1998 cb500s which I will own until I expire it’s so reliable and comfortable and doesn’t try to kill you, later this year after my cancer treatment I am going to treat myself to a xsr700 as they look nice and receive good reviews unfortunately I don’t have enough space for three bikes so my cb600 hornet will be for sale on eBay

    1. I had an XSR 700, brand new, for two years. Great fun on a and b roads, easy to wheely if you are not careful (as I found out 🙂 ), economical but awkward to work on (in my view compared to bikes years ago back in the eighties) and sketchy at speeds over say 80 mph due to it’s lightness. ( get it up to a ton and you will feel like you are hanging on for grim death as the front end is so light and twitchy) Not too comfortable on a 1 1/2 or more trip. A good reliable engine though. This is just my opinion, I’m 60 so that probably effects it somewhat.

  2. I’ve always loved twins..firstly and mostly Norton w/360 cranks (old school) ’68-’75 Commando’s. Gutsy, powerful and I surprised a many Jap bikes in my day. Also I have had Triump’s, Ducati’s and Moto Guzzi’s from basically the same era. Loved them all for different reasons..
    My youngest son at 32 y.o. has recently acquired a perfect example of Yamaha’s MT 07 with the 270 degree crank that you have been exploring. I must say I’m impressed..!! Made a believer outta me..! Smooth, Fast and Torquey..! Phenominal bike.! The science is proven in this example. Thanks for the article..!

  3. “See two exhaust pipes? You found yourself a parallel twin!” Not if it’s a single with a twin ported head, e.g. Honda XBR500. I really enjoyed the animated section, thank you. Best wishes, Matt.

      1. Did you know that the Yamaha XS650 twin had a splined shaft that you could split the crank and use the spline to create a 270 degree twin? You could also break the the crank and move one cylinder 3 splines forward and press it back together and tig tack weld the flywheels to the shaft with the proper amount of spread of the rods for a 277/83 degree angle. There are many on U-tube. A bit OT.

  4. By “The 270-degree crank is always in motion” did you mean to say “One piston is always in motion with the 270-degree crank” since the crank on the 180 and 360 cranks never stop either? You have that under the very helpful simulation of the three types but may not have been what you meant.

      1. I think you were actually correct to begin with Dana. The pistons and crankshaft are of a piece since they are directly joined with the connecting rods. If both pistons come to a complete stop at the same time as is the case with the 180 and 360 cranks then doesn’t the crankshaft have to completely stop as well?

        1. Rather than talk about stop/start, I think it’s clearer to say that in other crankshaft configurations, both pistons reach the apex/nadir (the inflection point of their movement) at the same time.

    1. Thank you very much for this insightful, informative and easy reading article. Much appreciated. Thanks

    1. Hi Adnan. Maybe you meant to comment on a different article, or maybe you misread that this is about parallel twins. I don’t believe Harley-Davidson makes anything other than V-twins.

  5. Wow, you said Honda rarely made parallel twin engines in the past. That is absolutely a false statement. Honda sold tons of 350 twins in the early/mid ’70s. Along with that, Honda also sold many 125, 160, 175, 305 and 450 twins. I personally owned a Scrambler 175, SL175 and SL350 during my teens. They were all 180 degree cranks, I think, except for the 305’s 360 degree crank. I heard of a guy around Gainesville Florida who cut the camshaft of a 305, turned it and re-welded it so that both cylinders fired at the same time like a twingle.

    1. I guess my personal sense of history doesn’t go back that far — I tend to start thinking from the 80s as it’s so hard to find bikes even of that vintage. I’ll make an edit. Thank you!

    2. 60’s Honda Dream bikes were twins. The Hawk and Scrambler had a 360 crank and two carbs, the Dream had a 180 crank and single carb. Cool!

  6. Another big factor in the use of ptwins has to do with manufacturing. They are less costly for manufacturers. In an interview with Asphalt & Rubber Miguel Galluzzi of the Piaggio group said a major factor in the rising use of ptwins was “packaging,” that they were easier to design around.

    I am not a fan of ptwins, but I really enjoyed the graphics and sinusodal visualization.

  7. Be nice if you had included two-stokes as well…ie. do they have the same three crank configurations? obviously the ‘Bangs’ will be different so would need a new graph as well.

    1. They normally use 180 degrees configuration, since 2T engines combust once per each revolution, thus this configuration which creates an even firing interval.

      BRC is developing a modern 2T inline-twin for the YZF-R6 chassis that employs the 180 degrees design, you can check it out on their website.

  8. My KTM 890 is a 270 degree P-Twin. I find it buzzy as anything at around 4,500 rpm. My GPZ500 which I believe was a 360 degree p-twin was definitely smoother.

    The 270 degree crank is mean to sounds and feel more like 90v twin, and whilst I’ve not ridden a 90 degree v-twin my 950 adventure was 75 degree, and my Falcon SL1000 60 degrees. Both were smoother and more pleasing engines.

    So far I’m not a convert.

  9. Thanks for an call on the importance of 270 crank engine. It is a practical article because it doesn’t go back so far on models that you typically can find or afford. But it was fun to see others make corrections on older bikes good on ya mate. Keep up the good work thanks again.

  10. Just read your article. Enjoyable. I have a VFR800, ST1100 very smooth V4s. Still have a CX500 Eurosport now 40 years old. My main rides in recent times have been Suzuki V Strom 650 then 1000. Good bikes but heavy, the 1000. Recently changed to a Yamaha Tracer 7. Brilliant. Love it. Just done 200 miles in Wales today. Smooth, enough power for solo and lighter than v Strom. , or any of my other bikes. Thanks for your article. Ken

  11. Please note AJS and Matchless twins have separate cylinder heads. I have AJS500 and also a TDM900 oh and a 750 Triumph just something about twins i guess. Good article thanks.

  12. The photo captioned F900R BMW engine is actually a previous generation Rotax built F800R – a completely different engine to the current generation.
    As described later in the article, it’s the (360° crank) engine fitted to the F750GS and F800R/S/ST/GT. An interesting feature of this engine is that rather than balance shafts, it uses an additional central crank pin that actuated a reciprocating arm (similar in concept to the Ducati Supermono single cylinder race bike.
    Speaking of Ducatis, they built some beautiful single cylinder bikes in the 70’s and are about to release a single cylinder motorcross bike that many hope will see its engine used in a lightweight road-going motard.

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