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Preferred engine configuration.

Isn't that the design that has a considered weakness due to no center crank bearing? Never owned one, can't speak to them personally, just what I've heard and read.
Well, there's theory and then there's reality. The reality is that there are untold numbers of those engines out there that are decades old and still running fine. Meanwhile there are not piles of broken crankshafts from them in junkyards, or at least I've never seen them if there are.
Also, Harley V-twins have two pistons sharing a single crankpin with no center bearing, and some racers build those to 300+ horsepower with superchargers and/or nitrous.
 
Well, there's theory and then there's reality. The reality is that there are untold numbers of those engines out there that are decades old and still running fine. Meanwhile there are not piles of broken crankshafts from them in junkyards, or at least I've never seen them if there are.
Also, Harley V-twins have two pistons sharing a single crankpin with no center bearing, and some racers build those to 300+ horsepower with superchargers and/or nitrous.
Totally aware of the Harleys, worked on them for years but their design is a bit different and really beefy compared to some pictures I've seen of Brit cranks, but as you say the proof is out there and not excessively in the junkyards.
 
Relating to the Parallel twin set ups talked of above, The 360 Degree has the worst felt vibration issues and the worst pumping losses in the range. But the Power delivery is undoubtedly the most constant in nature and tend to be the most torquey as a consequence.
The 180 degree is a different animal in that the vibrations although still there obviously are in the vertical plane counter acted but the vibes are horizontal planes thus more a rotational aspect or to use the proper term a rocking couple.l
The 180s vibes tend to be more humanly acceptable as a generalization, and lets not forget both 360 180s and the 270s can be counter shaft balanced etc and vibes are just not a huge thing in such cases, it tends to be most felt and moaned about in the older british twins that were just raw undamped motors built to be light fast simpe and cheap which despite their crude nature they delivered in spade fulls .
The 270 twin is just a middle ground layout, which in bigger capacities especially makes good torque with less pumping loss and more power delivery consistence, and the broader / longer intake time pitches it between the 360 and the 180, and makes the 270 a user friendly twin, and its current popularity id evidence of this.
The 270 is a good choice, its not as raw as the 360 or as flexible as the 180 and its power delivery is not as gentle as a 180 either but its a perfect twin compromise.
 
My Versys 650 has a 180 degree crank and it's a great engine. It doesn't quite have the character of the 90 degree V-twin in my old SV650 but it's still a great engine. I think the uneven firing order makes it feel somewhat like a V twin at lower RPM. I don't see what advantage there would be to a 360.:scratch
 
My Versys 650 has a 180 degree crank and it's a great engine. It doesn't quite have the character of the 90 degree V-twin in my old SV650 but it's still a great engine. I think the uneven firing order makes it feel somewhat like a V twin at lower RPM. I don't see what advantage there would be to a 360.:scratch
Well the c360 is a simpler set up, it can be easier to get adequate fueling from say a s ingle carb down to the longer intake interval, and the power strokes are far closer together giving a more linear deliverey. This as the trade off in the vibes as the two pistons stoping and starting together etc . the 180 is posite and cansels out the mass with the other piston but its thus transmited into horizontal vibes and more rotational vibe rather than shaker of the 360.
180 is a very uneven beat and this translates into less linear power but can help with tractibility with its motion, ideal for say keeping traction on lose ground or hill acents etc. the 180cc twin imo is prefereble to the 270 but its compromised by its layout more, and the 270 has gained ground these days to both the 180 and the 360.
The 180 despite popular rumour will run great on a single carb, i had to do this to prove it to myself with an ER500 kawasaki 180 motor, that was fine on single 930 amal carb on a mild steel manifld i made up. There is little if any hard facts on the WWW surounding the single carb on 180 crank, just the corect assumption the 180 duration timing sugests a 180 single carb is a no go. But in practice i was simply not convinced the theoretical shortfalls, would stack up as a fail, so i tried it and know its possible and certainly with a 90s kawasaki 500 twin.
 
The 270 cranks make a great sound. With the firing so close to each other they make gobs of off idle torque, but that ultimately depends on cylinder head design and cam profile.

Either way you cut it, big bores deliver torque quickly, which is what I love about thumpers. Don't think I'd want a 700-800cc thumper due to inherent vibration issues, but a twin in that size will give you the big bore oomph in a more civilized package. If you start cutting 800cc in to four cylinders you lose the big bore/ lots of torque at once effect.

My 70hp FZ 07 with a 270 twin had torque that hit so hard (689cc). My 120hp FZ 09 (849cc triple) makes the same torque at the same rpm while having gobs more hp. You have to yank on the throttle of the triple to get the front end up. The little twin would constantly surprise me with wheelies in 2nd/3rd gear when I wasn't even trying. Both bikes weighed 400-405lbs soaking wet.
 
Remember the Twin thing as in most anything engine is a degree of compromise. and the 270 being the kind of middle ground it fares reasonably well overall , but remember much of the theoretical benefits in the various degree crank twins are indeed just generalizations. And to get the whole story you might need to look at or research perhaps the specific engines build/ design details to understand the reason x is more powerful than y , and trust me it will be way more than just crank layout.
I mentioned Pumping losses on the 360 and how the 180 has a significant theoretical advantage . But though THEORETICALLY that's the case, in truth the design features employed in any given engine play possibly a more significant part in if say a 180 is indeed low on pumping losses. And equally so the 360 which could be less by good design.
Its hard to put in to text and give detailed explanation and examples, but this video from the workshop as ever with his videos is explanatory and i think will help explain the pumping loss thing if you needed it explaining a little better.
 
I love all this discussion, and I wish I could ride a 270° twin because I love twins. I've owned both 360° and 180° twins and they both have the benefits and sound styles.
 
Offroad and in town riding: 270 degree ptwins around 700cc. Lighter than vtwins, gobs of low down power with excellent acceleration. Sure, you don't get screaming high speeds, but you get a very fun bike up to around 110mph. Really awesome for everything other than long distance touring and super sporty riding.

Touring and very aggressive riding: 900ish Triples. Like the above, you're getting good low down power, but you've also got a good top end capable of felony speeds. Yeah, you're not beating i4 supersports in a straight line race, but anything more complex and it's all the rider anyways.

In both cases, a major part of both is the sound. 270 degree ptwins sound as good as vtwins - none of that gross Kawasaki 650 boringness - and who doesn't like the sound of a bigger triple spooling up?

If I had to pick only one motorcycle though (God forbid I ever have to go back to that) it would absolutely be a 270 degree ptwin.
 
I love all this discussion, and I wish I could ride a 270° twin because I love twins. I've owned both 360° and 180° twins and they both have the benefits and sound styles.
I have owned 4 parallel twins and three V Twins. I never thought about the crank angles when I owned them until my present Versys. My first bike was a KZ400. At around 62 MPH it became a jackhammer. The rest of the twins I have owned have been pretty smooth. The V twins had the most character but but the engine in my Versys has a good feel to it as well. It has a broad torque range and revs quickly.
 
I have owned 4 parallel twins and three V Twins. I never thought about the crank angles when I owned them until my present Versys. My first bike was a KZ400. At around 62 MPH it became a jackhammer. The rest of the twins I have owned have been pretty smooth. The V twins had the most character but but the engine in my Versys has a good feel to it as well. It has a broad torque range and revs quickly.
KZ400? ASAICB are 360 Degree. The old XS2 650s etc were the same. You did get the Brit bike vibes which either you loathed or absorbed i was just primative and knew no better. n But i will say to of my all time favourate motorcycles were both 360s a tigerT 90 350 and a tiger 750 TR7V 140 , both were single carbs funily enough.

The verseys is 180 sort of a bigger stronger more modern version of my little old Pet bobber EN500 A3. which is 50 hp and 30 years old. The ER6 Lightweight TT super twins (Motor Bassed on verseys motor) Are lapping the TT at 120MPH so kawasaki must be doing something right and the 270 aprilia 650s competitors are still in the limelight compared to the now aging kawasaki 650. now if the crank throws have anything significant to offer on the raggy edge of twin tech, i can not say just saying.
 
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Two stroke big bore twin.


Wait that wasn't in a bike. I guess 270 parallel twin since that's what I am likely going to have the most miles on in a couple weeks.
the big two strok twins are an awesome motor, Did several alpine tours on a Suzuki T500 and a great engine for touring . The Suzuki did have a buzz y vibration to it, and like many of the two stroke twins back then, after a prolonged thrash , you arrived at your destination and the zero vibes off the bike made you feel flat as a sack it used to feel like the world had stopped suddenly. :lol2.
I rade a 1974 RD200SX and even though it was a small st twin it had that zingy buzzy vibe to it and had similar outcome. Strange but Never felt the vibes to the extent on R5F 350 yam or RD400 or RD350 LC VPVs. The cT500 and the RD200SX just seemed to be harsh in the felt vibrations.
 
the big two strok twins are an awesome motor, Did several alpine tours on a Suzuki T500 and a great engine for touring . The Suzuki did have a buzz y vibration to it, and like many of the two stroke twins back then, after a prolonged thrash , you arrived at your destination and the zero vibes off the bike made you feel flat as a sack it used to feel like the world had stopped suddenly. :lol2.
I rade a 1974 RD200SX and even though it was a small st twin it had that zingy buzzy vibe to it and had similar outcome. Strange but Never felt the vibes to the extent on R5F 350 yam or RD400 or RD350 LC VPVs. The cT500 and the RD200SX just seemed to be harsh in the felt vibrations.
I've had two 600cc Skidoos and one 850. That 850 is rated for 165hp and could go zero to "oh shit" faster than I can comprehend.
 
Having nothing to do with power or performance, I’ve long found the twisting from a transverse V-twin appealing. They’re somehow different from the flat boxer, which also twists the bike sides.
 
An Engine i am interested in, and one if it ever becomes proper mainstream could be the salvation of internal combustion in motorcycles and cars/ trucks /vans at any rate.

I wonder what that thing sounds like.
 
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