We had a number of two strokes in the family growing up, but one of the most interesting was how Kawasaki ducted the carb to the side of the engine in a rotory valve configuration. Not in itself revolutionary, just unusual for a mid 60s design. I think that it was a 100cc dirt bike that my brother and I were trying to modify.
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Nah thats a little unfair. Compactness, Weight, ease of repair, maintenance, in field service and rebuild, heat generation and control, moving parts,
All better on a 2 stroke.
The only way a 4 banger is better is longevity, emissions control (and thats only because cars use them and they had the research actually given to them by necessity), torque and a larger spread of power.
The larger spread of power is actually arguably not as important as it once was due to gearbox improvements. Cars having 9 and 10 speed gearboxes would have been incredibly helpful for 2 strokes, hence why they were such a success in lorries
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This has always been a great way to find out how commited to engine design a manufacturer was. If they nicked the idea…it was normally a very poor engine.
If they nicked AND improved it however!
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Yes and no. The exhaust ports for the V-Due are at the back of the cylinders which allows for a straighter and more efficient expansion chamber but meant that with the important part of the exhaust under the seat they had to do what they did with them to have room for the mufflers. Without them sticking out too far from the rear cowl.
The only thing that matters with the ‘stinger’ (the end/tail piece of an expansion chamber exhaust) is the diameter, Length is irrelevant.
All the magic happens with the header section, reverse and forward cones. They generate the reverse pressure wave that forces the unburnt fuel air mix back into the cylinder. It is actually a form of supercharging.
As you can see with the expansion chambers for my RGV, the stingers are different lengths. Although the shape for the header, and cones is different (i.e. curvature) the dimensions, especially the tuned length, are identical.
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Also used by the square four Suzuki GP bikes of the Barry Sheene era and the road going RG500.
Finicky to set up the timing right, crankcase seals prone to failure and surpassed by the much simpler reed valves.
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Man this is just a terrific discussion! And one I should perhaps pay more attention to. Because in the now unlikely event that the Trump Tax doesn’t destroy the company building my latest (uggggg) helicopter kit, it will be powered by a water-cooled, fuel injected Suzuki 2-stroke.
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I don’t even need to click that link to know that is about the MZ scandal. One of the greatest and most interesting bits of corporate espionage that nobody ever heard of.
Amazing
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FortNine made a video about that story, ever since I had the book on my to-get list!
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Absolutely fascinating 
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Agreed. Fascinating. Also… the weirdest ad placement I’ve ever seen.
The book is $105 on Amazon!
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Edit: Should have watched the whole video before posting… But anyway.
Yes the RG500 was brutal (I have ridden one), the whispering death referenced in Matt Oxley’s book, although another Suzuki was this particular beastie:
But by far the scariest two stroke I have ever ridden (well it is a toss up between this and the Yamaha IT490), Is the Kawasaki Mach III:
Flexible frame, questionable suspension, non-existent brakes and way more power than is sensible. And like every air cooled two-stroke you rode it with at least one finger covering the clutch for when (not if) it nipped up and tried to spit you over the high-side.
Holy Carp Batman 
I’ll tell you what. If you can’t find an e-book version and are really keen to read it. I will mail you my copy, provided you return it once you have finished with it.
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That is the kindest offer imaginable…to a stranger no less! Your book is safe as the kindle version is $7. I’ll read it. But my mind is sorta blown already. V1 to 2-stroke? What a crazy history. It seems the world stopped being interesting just around 1968, the year I was born. Coincidence?
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A stranger is just someone you haven’t met, yet. And I like you Eric, so what if it costs me a few bucks in postage to enrich the life of someone I like.
You might be surprised at the number of fellow Mudspikers that know my real name and address because of stuff that I have sent, swapped or bought from them 
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As someone who grew up in the former GDR I can tell you that two-stroke engines were very much alive and in production until 1989
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Apologies in advance if this is if this is insensitive. But all I can think of when I read that is ‘Go Trabi Go’.
I actually like that movie and think that to own a Trabant would be pretty cool.
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No worries. It’s a funny movie. I’m surprised it’s known outside of Germany.
The GDR struggled to provide enough consumer goods for its own citizens to meet demand. You had to wait around 10 years after order to get your car. I remember my grandpa had a frog green 601 and it was a big deal. Compared to today, the streets of East Berlin were ridiculously empty.
It was common to get “Gemisch” (Petrol and oil) directly from the gas pump. I don’t miss the noise and smell
Tbh, I never was attracted to two strokes for that reason once I was old enough to drive myself.
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We have a free to air TV channel dedicated to foreign language broadcasts. Movies, documentaries, current affairs, TV shows, etc. Plus I can cope with sub-titles, besides I’m half deaf these days and tend to use them for English language shows as well 
Lots of good stuff, e.g. I’m a bit of a fan of ‘Nordic Noir’ and only recently watched the latest season of The Bridge.
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Grrrr saw a military trabant at Gatwick the other day and didnt take photo!
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