270° Parallel Twin Engine: Why It's The Best Form of Parallel Twin Engine?

[@nikolaigrut]

Thanks for the video. The firing intervals are immaterial to the vibration issue. The exhaust note - well, no one should care other than those who write copy for a living. The key thing is inertial imbalance which grows exponentially (or is it squared?) with increasing revs. I don’t think the earlier 360 twins had a balance shaft so you might be wrong there. Did you mention BMW:s 800 cc engine with a genial third connecting rod and counter weight? Or the T-Max’ third dummy piston? (Also coming on SYM TL 500). Regarding 180 parallel twins - a primary rocking couple - yes but essentially balanced away with a balance shaft. The drawback with 180 parallel twins is the unaddressed SECOND order vibration (also on inline fours). And I agree with you on the 270 parallel twin - the second order vibration cancels by the design of the crankshaft if you disregard its rocking couple. But they too need the balance shaft for cancelling the first order vibration. How come the 270 parallel twin came to market? Advances in manufacturing which made the crankshafts cheaper to make. Thanks anyway. You can also disregard the fluff about power pulses. Other than at low revs, this is immaterial. And anyway, the 360 parallel twin has the most even powerpulses.

[@RevvingHeart]

Wow, that was some great observations. I was just trying to explain it simplest way possible and I think a few points got lost in that process. Thanks for pointing out the flaws.

[@tallioegian]

SECOND order vibration - hmmm. Please produce a video explaining that:)

[@nikolaigrut]

Michael Thompson, it looks like this guy will explain second order vibrations: kzbin.info/www/bejne/nZWrgmuXicuch7M

[@nikolaigrut]

And yes, of course also second order vibration can be balanced out but is not yet done by balance shafts on motorbikes. But several cars do address the second order vibration by double balance shafts that turn twice as fast as the crankshaft, e.g. Porsche 2.5 liter inline four and I believe several Honda engines.

[@billwessels207]

@@RevvingHeart Very diplomatic.

[@trailingarm63]

That was a brilliantly clear explanation. I think I've finally got it after wondering about it a million times when reading motorcycle magazines. Well done and thanks for posting.

[@barryervin5297]

I've owned parallel twins with 180, 270 and 360 degree firing orders and I like the 270 best. They run smoother and sound best to me. I actually converted my 1978 Yamaha XS650 from 360 to 270 (actually 284) and it definitely runs smoother and has a more interesting exhaust note. I doubt that it makes more power though and probably wasn't really worth the work involved but now I have something different.

[@orbarends]

That's really cool! If you ever make a video about this I'd like to see it.

[@barryervin5297]

@@orbarends No video, I did this about 20 years ago when I had to figure it all out for myself and everybody told me it wouldn't work. Today you can just buy the crank and cam and ignition system online and bolt it all together. I definitely thought the conversion ran smoother and sounded better, and guys with stock XS650s who rode it usually agreed . My new Honda CB500 with the 180 crank sound's terrible, luckily I like quiet exhausts anyway so I don't really have to hear it much.

[@MegaBoilermaker]

I had a TRX 850 with a 270 crank.

[@barryervin8536]

Nice bikes. I can't remember now if we ever got them in the US, if so I've never seen one.

[@MegaBoilermaker]

@@barryervin8536 Quite rare anywhere Barry, The dry sump engine was developed from the XTZ Paris-Dakar race engine. The frame was quite good and handled almost as well as my Ducati. A good friend still has two of them.

[@richardmorgan1588]

I don't think anyone else has stated this concept more clearly! Thank you!

[@PhantomRides]

I've heard many people talk about the 270 degree engine but no one explained it like you did. Thanks!

[@marvinr5054]

You have answered so many questions that I had about my Truimph T120 engine in this video. Thank you.

[@arnonanun654]

Very informative buddy. Good job

[@rcnelson]

Very well done. You gave a clear explanation with helpful graphics. I gotta admit that I still prefer the perfectly even sound of a 360 degree twin, and Norton proved many years ago with its Isolastic system that one needn't counterbalance such a twin. A thumbs up video all around.

[@nikolaigrut]

Good point you made at the end about the 90 degree twin. You hear that after all, it runs a little smoother than the 270 parallel twin. And there are some great and expensive and less expensive 90 degree twins out there. We have perhaps the best known from Suzuki and Ducati. I’m sure they’ll hold their market for a good while. At the same time they are more expensive to build, which you also mentioned, if I remember correctly.

[@adamdelarozza1985]

So a 360 degree crank is like having a single cylinder engine since they both are uP & down at the same time; that's a better perspective than i had before, thanks for clearing that up in this video!

[@alrecks619]

i'd say it's a breathe of fresh air to the market that is already oversaturated with 180 degree twin sport bikes.

[@gardnerberry113]

Thanks! Now I won't look as clueless to my gearhead friends!

[@barnabaskiss2888]

Good summary, just a remark: a 270°parallel twin is not equal to a "real" 90°v-twin in terms of balance. 90°engines have perfect primary balance, no balance shaft needed. So the vibrations are different and the sound isn't perfectly the same, as it depends on not only the firing intervals (just the exhaust note, but there are some auxiliary noises that make it special and characteristic).

[@cameron.naidoo]

having owned a 270 degree crossplane (MT 07) and currently a 90 degree v-twin (V-Strom 650) - I can confirm from experience that only the exhaust note is mildly similar ... the feel is very different, the vtwin is much more balanced at low revs and the power delivery feels smoother overall while the 270 parallel twin had a more erratic feeling power delivery and only felt equivalently smooth at the higher rpms (after 4500 rpms). both are a hell of a lot more interesting than a 180 degree parallel twin and produce better torque/sound in my opinion.

[@akashjoshi88]

Very well explained... Thank you...

[@Tony455HO]

Very informative video, enjoyed watching it. Keep up the good work. Cheers!

[@stephenbethell7548]

Explained very well, thank you .

[@ProDigit80]

I like ptwins on 360/180 degrees, like the Honda Rebel. They're butter smooth around 2.5-3k RPM, but vibrate a lot between 4-5kRPM. But then become butter smooth again around 6k RPM, and again at 9k RPM.

[@JAG312]

Although the 270 degree crank seems to be the best for a two cylinder engine, I prefer the three cylinder engine of my Triumph Legend.

[@JamesWillmus]

Here's a fun fact. Steam locomotive pistons had to be calibrated in a process known as "quartering". Quartered locomotive cylinders balance out the massive forces acting on the engine, conserved momentum between each stroke, and allowed the train to run smoother and achieve higher top speeds. This concept has carried over into internal combustion engines and is what led to the development of the 270 degree parallel twin engine.

[@bennetteberle4476]

It also allowed the steam engine to self start in any crank orientation. Top and bottom dead centers were called dead for a reason. If a single cylinder steam engine stopped in either of those positions, someone would have to manually rotate the engine off of that position before the engine would start. That would be hard to do with a locomotive.

[@Diesel415]

Since the 70s the Yamaha XS650 motor was a popular one to rephase to 270° (actually 274° because of the crank splines). In the 90s Yamaha introduced the TDM850 to the US market, a liquid cooled parallel twin with a 270° crank but sadly it didn't really sell well.

[@1998TDM]

Sadly indeed. The TDM is a great bike and gorgeous motor. 270o from the MkII onwards, pretty sure it was only the MkI that was sold in the US. Yamaha's 700cc twin is a direct descendant.

[@willburton6622]

The TDM850 was a great bike - I spent a week in Scotland on one, and it was an ideal bike for the journey. Did not lack power on the Motorway, either!

[@tonydoggett7627]

The point of 270deg parallel twin and 90deg V twin is piston “speed”. When a piston is at 0 velocity (TDC or BDC) the other is at maximum velocity mid stroke (up or down) and vice versa through the cycles. 🦘🇦🇺

[@edwardweiszbeck1649]

Thanks for the good explanation Sir. 👍

[@BurningPXG]

You deserve more likes. Great effort put in those videos! Keep it up!

[@faustin289]

Woow. These animations are very intuitive. I can understand what's going on and capture the essence of the message of the video even with the voice muted. Kudos!

[@Dave-sw2dm]

When I was looking at the classic line of triumphs in 2014 I thought I wanted a Thruxton. Then I rode the scrambler and the engine did so much more for me with its 270 degree crank. That set me off looking for a dropped scrambler to turn into a thruxton. In that search I came across a Moto Guzzi V7 Cafe and haven't looked at Triumph since.

[@hugoaken2604]

My 2012 Thruxton EFI does have a 270 degree crank.

[@genegoodwin8925]

I know the 270 degree crankshaft has less vibration than a 360 degree crankshaft, but I grew up in the 60's when BSA and Triumph motorcycles were the hottest bikes to own. Their wonderful sound was due to their 360 degree crankshaft. The new Royal Enfield twins really interest me, but the Kawasaki W800 with it's 360 degree crank and chrome fenders would be my choice today, vibrations and all.

[@ivok9846]

how do you know 270 has less vibration?

[@genegoodwin8925]

@@ivok9846 Experoence. I've ridden both.

[@ivok9846]

@@genegoodwin8925 me too, and any 270° bike I rode (most new parallel twins are 270 anyway) feels like a tractor compared to 360° xtz750...half way between 1 cyl thumper and 360° twin... that's why they're compared to v twins, because they're running rough...

[@GrtSatan]

Very informative and well presented. My 790 Duke has a 285 degree firing interval but is essentially the same.

[@chrishart8548]

Or a 75° firing order. The 270° is also a 90° both add up to 360°

[@StupidEarthlings]

Cool. I was just killin time in Drs office, and clicked. I never really thought of this before. I would have guessed that the 180 woulda been best.. but there ya go.

[@StupidEarthlings]

Although, personally, I prefer the sound of my Vmax's rip roarin V4.. but to each his own.

[@barryolaith]

And then there's the 90 degree (cylinder angle) 'transverse' V-twin which is actually a longitudinal v-twin since the terminology refers to the crank orientation. This in my view is the best layout for an air-cooled twin. Moto Guzzi know a thing or two about this.

[@maskedavenger2578]

So do Honda they built the CX 500 transverse V twin shaft drive & went one step better & made it liquid cooled with slightly offset twisted barrels to tuck the carburettors in nicely .

[@mikekokomomike]

Wasn't the honda more like 80 degrees?

[@maskedavenger2578]

@@mikekokomomike I always thought the Guzzie was less than a 90 % V Twin ,never really took much notice of them as they are Italian with dodgy Italian electrics ,& being of a low seat height were more suitable for women & vertically challenged male riders .

[@mikekokomomike]

Guzzi is a 90 degree engine v angle, and the CX Honda is 80 degrees. I worked with a guy had CX650 Honda with a turbo. Me, I ride flat twin BMW

[@maskedavenger2578]

@@mikekokomomike Never understood why anyone would buy a motorcycle with a big cylinder pot sticking out each side .Even fitting them with engine guards only adds weight to the huge over the top tin boxes & masses of Tourtech farkles & tat ,that makes them tractors prone to ending up side down on the deck .

[@eatcommies1375]

Love my 270 super tenere twin. Great explanation!!

[@budakcina1446]

i looked all over the internet and this has to be the best explanation for me

[@rdaystrom4540]

Great video. I learned a lot. Good job. Thank you.

[@Oddman1980]

"Has the balance of a big single" *Cries in DR650* My brother got a Royal Enfield GT650 two years ago, and it sounds amazing with good exhaust.

[@mickmondeo]

Wow! I learned a lot for this. Sub’d!

[@douglas9607]

Very good. Thank you for the vid.

[@AndrewBoundy]

Great video - thanks! I learned something :-)

[@garypeatling7927]

Great explanation

[@7GtwNYkHYs]

good video

[@realname2404]

This channel is surprisingly good! Keep up the good work!

[@ahmedAli-ok7gz]

Good quality contents and very informative

[@FBFerran]

Very clear explanation and nice of you to mention the sources of your video material. I really liked this video.

[@devonnewest7990]

BEST CLEAREST VIDEO ON THE TOPIC!!!!!

[@biswanathmohapatra1836]

Now this is a good topic✌️👌

[@RevvingHeart]

Hope you find it informative.

[@Shikiouji]

that visual display if the different cranks was brilliant.

[@Gringo_In_Chile]

When comparing the pros and cons of 270° parallel twins, other engine factors should be taken into consideration. Since this video examines 3 inherent characteristics of 270° parallel twins: vibration issues, exhaust/engine sounds, and cost of ownership / manufacturing. I will examine only one specification (of many) that can affect all three of the issues listed above: engine cooling. • Air-cooled engines typically dissipate their heat through fins seen on the cylinders, and often the head itself. • Air-cooled engines require fewer parts, both for manufacturers to build and for consumers to fix, maintain and replace (radiators, pumps, coolant). • Air-cooled engines provide more simplicity, representing less components, which could break, need to be replaced, or need servicing. (radiator, pumps, coolant change intervals, electric fan, etc.). • Air-cooled engines run richer, making them less efficient and more polluting. • Liquid-cooled engines replace air-cooling fins with an additional layer of aluminum casing to create a "water jacket" for liquid coolant circulation (more engine mass). • Liquid-cooled engines having the cylinders and heads jacketed and surrounded with flowing liquid coolant act as sound insulators and deadens mechanical noise making them significantly quieter than air-cooled engines. • Liquid-cooled engines - circulating liquid evens-out hot and cold spots in the cylinder head for better emissions and more complete chamber combustion. • Liquid-cooled bikes can rev higher because they have higher tolerances due to their ability to self-cool.

[@Gringo_In_Chile]

Thanks!

[@galuhrichata6148]

Short, simple, but very clear explanation.. please make more..

[@ianroscoe6745]

Excellent explanation of why my NC750 is such a great ride, thanks.

[@radiocrash]

Top quality video!

[@curtn7076]

I did not know that. I was lucky to test ride the gt650 in Miami FL for a demo. Very smooth and balanced bike. I've had about 15 bikes so for and may buy this one. Even the 500classic is cool.

[@spacetruckin6555]

So well explained and animated that even I learned a lot from this video! Right on, just explain it to me like I'm fourteen years old.

[@siddhantbaranwal5339]

Thanks for explaining

[@straycat62]

Great job explaining. Thanks

[@bazbbeeb7226]

Same as my old Yamaha TDM 850, a beautiful sounding bike.

[@naveensanders4293]

Superb video mate ...

[@blueroadsroll]

Very nicely done! The animations and the explanations that you provided with them were really helpful. Thanks for taking the time to show all the details.

[@skyb8687]

Hey revving heart ,great video sir,Thanks!

[@ethan073]

Exactly the kind of video I was looking for. Thanks 😀

[@sethbrown1763]

Thanks for that very clear explanation!

[@raymartcollado8708]

If the rebel 500 has 270 firing order, it would be great.

[@RevvingHeart]

Totally agree...

[@leoedward7363]

Best explanation yet, thanks

[@mikewho9964]

Its true the 270 crank has many benefits but the BMW F800 series engine is a 360 crank and i would argue is a more playful motor and sounds and feels more like the Yamaha RD400 two stroke . BMW solved the problem of vibration ( mostly ) with a 3rd conrod and balance arm - much simpler than a balance shaft ( chains and bearings )

[@vesandreev7864]

Great video! Thanks for the clear explanation! Keep the good work!

[@billwessels207]

Avery nice video. Thank you so much Sir.

[@jeffslade1892]

Ignition occurs before top dead centre (BTDC) so that combustion is /complete/ by TDC. The piston is not driven by the explosion (it's not a proper explosion anyway, more a fast burn) but by the expanding hot gasses including the non-combustible nitrogen. This is why the ignition is advanced as revs increase, the combustion time is fixed but the piston speed varies with revs. Ignition is typically 17°BTDC (static) advancing to maybe as much as 37°BTDC as revs increase in some cases; not really a short way before TDC.

[@andyblack5687]

I had been wondering why these new parallel twins sounded more like v-twins compared to the old parallel twin engines. Now I know why, thanks to your explanation. Thank you.

[@morelanmn]

One of your best videos

[@mohanmch]

Nicely done. I was searching for this ever since I heard that the next generation of Suzuki V-Strom 650s are going to be parallel twins. I figured that that would raise the CG and rob the motorcycle of its character. But with this 270 deg crank, maybe all hope isn’t lost just yet.

[@ennerdale541]

Easy explanation 👌 thanks mate

[@goodbadugly654]

A good video, thumbs up from me. I have a 270 Triumph and love it. One point though.... the moving graphic is wrong. No1 is always described as firing at 0, and no2 is therefor at 270, or 180 or 360.

[@Tobeon2]

Thank you so much. It makes perfect sense now.. I am currently riding 2017 Ninja 650 which I believe to have 180 degree crank... So, vibration is something I have to live with especially at the high revs.... but, so far, it has not been too bad.. (^_^)

[@JamesCouch777]

Best explaination yet! Moto Guzzi has one of the best 90° v-twins.

[@voornaam3191]

And Yamaha had the best one, the TDM 900. With 10 valves and lots of torque. Now there's only the Teneré comparable. I do hope that MT series wil reintroduce a parallel twin again. That triple is good, but what should the twin lovers do now? Restore a used TDM 900? Why isn't there a new TDM 1200 big twin? Yamaha is very capable to renew the TDM, it was a great concept. Why not update it? TDM 600, 900 and 1200?

[@JohnSmith-bx1mp]

@@voornaam3191 love a piped 900 triple...best sound ever.

[@timallen6025]

This is a great video with insight thank you 👍

[@flounder2760]

surprisingly good vid... i especially appreciated the firing/crank graphic

[@Trex531]

Very good and clear explanation, well done!

[@rocketrollsvlogs7625]

Great info. Excellent presentation.

[@medicorideramol8264]

Best explanation ever

[@cagr4249]

With 1 balancing shaft (of course best solution is 2 balancing shafts, turning opposite to the crankshaft but with crankshaft's speed) it is impossible to fully balance the "270°-engine", because "momentum of 2nd order" (=doubled crankshaft speed, sorry for my bad English) remains. But no question: the 270°-2-cylinder-parallel-twin is the best concept with regard to mass-balancing - and this is why it has become the common design. A flat crankshaft (360°- or 180°-design) would be the cheapest version, but nowadays even a spatial crankshaft like the 270°-version is not that much more expensive.

[@KARMAkazeMoto]

Helpful. Thanks.

[@eldorado5686]

Great job. Awesome presentation!

[@sgomez3047]

🤔 good explanation..I however will keep my "L" twin and the beautiful exhaust note that comes from my 1200S.....thanks for the video.

[@concordance5387]

Great explanation. I learned allot. Thanks.

[@tonywright8342]

very good, thank you.

[@nextlevel7790]

Awesome description .. Thank you.

[@76629online]

I’m still waiting for somebody to come up with a perpendicular twin.

[@cameronmadsen6490]

Loved the animation

[@mdiz4564]

Brilliantly explained! 👍🏻

[@cwilliams8647]

great vid

[@karthikvijayakumar2827]

Well explained..

[@TurboDirectSA]

Nice review!

[@apollo156]

Very useful and interesting!!!

[@AndyViant]

They're not just a new thing. My 1997 Yamaha TRX850 has one and I chose it over a Ducati. Indeed, later I bought the Ducati as well, sold it, bought a Harley. I still have the Yamaha though.

[@68404]

The Yamaha TRX850 was the modern leader of this trend. Such a character filled engine. It is also much cheaper to build a parallel twin than a 90 degree L twin (with duplication of heads, valves, cams etc).

[@harrykuntz878]

Good show thank you . My thoughts on engine design if you want a single the Honda vigor slr650 are affordable and easy to tune for a lot more power . For a middleweight twin the Honda v twin as used in the transalp duville and such is smooth as silk the Bros 650 being my choice way ahead of it's time . For a four cylinder it has to be a Honda vfr750 they have gear driven cams making for an almost silent engine and again way ahead of their time . Moving up to the big stuff a Honda varadero 1000 fi is a very practical proposition good mpg long rang tank touring fareing 3 piece panniers long tyre life and plenty fast enough too carry two persons across a continent on any type of road in comfort it's only down side is chain drive it can be overcome somewhat with a scottoiler . Moving on in cost a bit for a twin a Yamaha xtz 1200 is the clear favourite they look good too and are shaft driven . A less pretty more thirsty but it's all about the engine the big Daddy and the one to have is the Honda vfr1200 x . If you fancy a sports twin Ducati made some nice bikes the St series being their best kept secret all the trills with a bit of comfort throw in the dreaded belts are easy to change they cost a bit more to service than a Japanese bike but they are fun to ride . For me the most desirable bike around these days is a Honda nc700x dct very frugal biking and no need to change gear any more the engine is have a Honda fit/jazz car engine so they only rev to 6000rpm the sound great with an end can . The new royal Enfield 650 is pretty cool Harris designed the frame they are more affordable than a triumph and more like a 60's bike I think . I am not bothered about retro style myself .

[@bennetteberle4476]

Totally missed is the fact that on a cross-plane crank, the second harmonic vibration of the two cylinders are out of phase and cancel. The cancellation of the second harmonic imbalance is why almost nobody uses a flat crank in a V-8, even though a flat crank results in an even firing interval. The second harmonic comes from the toggle action of the connecting rod swinging back and forth causing the piston motion to be asymmetrical, higher acceleration at top dead center than at bottom dead center. The shorter the connecting rods are, the more severe the second harmonic imbalance becomes.

[@petewebb6952]

Very helpful. Thank you.

[@matthiashauptmann9423]

Apart from the mentioned disadvantages V-twins are not only more expensive to produce, but also to maintain. You got 2 cylinder heads instead of 1 and access to them usually has to be gained with quite some work.

[@jaybhatt8315]

Very much good information, continue...

[@irvhh143]

You have to ride one of the pre 1990 twins to understand how bad ths vibration is. This is the reason that the honda 750/4 put triumph out of business. It waz amazingly smooth for not having a balance shaft. If not for the vibration issue, triumph would have lost 40% of their customers, but they'd have survived.

[@jeanbidolat349]

I would like to know if a brand made a 350 or 450 but 270 degrees crank🤤🤤

[@geraldscott4302]

I have no idea why anyone would want to eliminate low frequency vibration. It is a huge part of why I ride a pre M8 Harley Davidson. Smooth quiet over refined Japanese bikes are drop dead boring. Harleys have a wonderful sound and feel. Then H-D destroyed all that in one fell swoop by putting a counterbalancer in the M8, effectively creating a Japanese engine, and putting an end to all the fun.