Probably one of the best layman's explanation of the difference between 180°, 360° and 270° engines I've run across.
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PARALLEL TWIN: 360° vs 180° vs 270°
- Thread starter Jim
- Start date
It certainly explains why the 360 went away.
bbbBut what about the best offset of them all the 277?? 
7% less of a compromise? Or 7% more?bbbBut what about the best offset of them all the 277??
That was really interesting! 
hovel
ol' stupid
I subscribed to his channel. Thanks for the heads up Jim!
I wholeheartedly agree.
As far as twins go, a 180° like the old Honda 450 Black Bomber runs a close second. Especially winding the gears out to redline. Mmm... sweet.
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Cool video, riding my XS650 and my Wife's CJ360 (180degree parallel twin) is night and day difference. The CJ360 (CB360 variation) winds like a sewing machine, and is much happier in the high revs. It is totally free of vibration but but lacks the low end and mid rpm punch of the 360 degree XS650. The CJ being a factory kick only bike is much easier to kickstart, cold it starts on the second kick EVERY time. When its warm it only takes about half a kick.
I think the low end and mid range advantage of the XS over a CJ360 is mainly due to almost twice the CC, and the general state of tune (i.e camshaft, ports et.al.) And not because of crankshaft configuration.
No love for a 9-10000 rpm, air cooled, 2 Valve, SOHC, 90 degree V-twin then?
JJames
XS650 Addict
Great video. I've always. Loved the sewing machine sound of the 180⁰ honda twins. I know that 270⁰ is a popular rephase for the xs650. Question is has anyone rephased an xs650 engine to 180⁰? Could it be done or would you be fighting the engineering used to "engineer out " the primary vibrations of the 360⁰ twin. If possible, what would be some of the pros and cons? Something to chew on.
I've toyed around with the idea of a 180° XS for years. The main problem is the crank center spline. It's either 6 or 8 splines... don't recall which... at any event, it won't allow the crank halves being reversed 180°. So, you'd need to make or have made a center spline for 180°
Other than that it wouldn't be that hard.
I’ve ridden a 277 XS650. The one I rode, I did not like. It was not smooth like a RE Interceptor or any other modern 270. It was smooth up top and awful at the bottom.
As the original balance factor is designed for a 360 crankshaft, it definitely not optimal for a 180 crankshaft, and not really ideal for a 270/277 either.
360 degree twins usually have balance factor in the 60 to 85 percent range, while a 270 should be better with close to 100 percent. And a 180 should have a much lower balance factor, I guess between 0 and 50 percent.
In any case, pushrod engines or twins with.an outboard cam chain/ belt would be a better starting point for a 180 or even 270/277. This because more tightly spaced cylinders will reduce the rocking couple.
Good point.
I wholeheartedly agree.
As far as twins go, a 180° like the old Honda 450 Black Bomber runs a close second. Especially winding the gears out to redline. Mmm... sweet.
black bomber is top of my wanted list! I have a 500t which is a long stroke 450. Doesn’t rev out quite the same but still a fun ride and a nice tone. It’s super light and compact too. Feels like a bike compared to an xs haha.
So, I take it the W800 has a 360 engine. It has to be one of very few.
Yes.
It's a long stroke engine, especially by modern standards - 77 x 83 mm. And by modern standards there's a weighty crank in there too. There's a balance shaft but apparently Big K chose to leave some unbalanced vibes to give the 'feel' they wanted. The design brief was to give the engine character and make it stand out visually, which is why we have air cooling with big fins and a boldly placed tunnel for shaft drive to the OHC.
I think they have met the brief with a lovely engine. Powerful enough for the class of bike on offer, revs smoothly but you can feel there is an engine in there. However, not quite as much character as the XS650 which feels, uhm, more raw.
And it works visually - even non-bikers recognise it as a proper motorbike.
