Would like to know who was behind the two strokes expension chambers? or did you know already? Fortnine seems to have that story!

[LowRyter]

this:

Spying and racing and WWII and Communism and Suzuki.  And it gets worse.

 

https://www.amazon.com/Stealing-Speed-Biggest-Scandal-Motorsport/dp/1844259757

 

Edited 19 hours ago by LowRyter

[LowRyter]

Very good read, @docc

 

better than plenty of fiction.

[docc]

16 minutes ago, LowRyter said:

Very good read, @docc

 

better than plenty of fiction.

I had to laugh at your comment, "And it gets worse." 

Makes me think of this Tom Clancy quote:

[LowRyter]

@docc it's a great book, well written.  Actually should be a movie.  IIRC, the expansion chamber, power valve and rotatory valve were invented here...inspired by the V1 rocket.  Betrayal and tragedy are in the offing.  As well as inventiveness with poor resources....

[guzzler]

17 hours ago, GuzziMoto said:

Two of my favorite two stroke experiences were racing a TZ250, which was a lot like the above mentioned TZ350, and a KTM 440 EXC dirtbike. The TZ250 was the classic two stroke, no power, followed by some power as you rev. Then, around 8,000 rpm it started to make noticeable power. At 10,000 rpm it kicked in and went, pulling hard up to around 13,000 rpm where it was done as quickly as it started. That bike was serious fun on a track. 

My other favorite two stroke was the exact opposite. The KTM 440 was a monster that didn't have to rev to make power. It was almost friendly at idle, but at some point just above idle it turned into a beast. It quickly went from making some power to making massive power. It was a dirtbike, so it didn't have a tach. But it didn't need one. The power was always there. It was a case of too much power being too much fun. I was not really faster on it then I was on my DR350, but my smile when riding it was way bigger. It would plaster a smile on my face the way it yanked me out of corners. It was like the way spaceships hit warp speed or light speed in sci-fi movies.

Expansion chambers can make two strokes deliver amazing power. They don't automatically make for a peaky motor, they don't always means power up top. They can make power wherever they are designed to. Thinking of them as acoustic resonance is a good way to look at them. Depending on how they are designed they can make power down low, in the middle, or up top. 

Heh he.

I got to ride a mates PE400 ( detuned mx for enduros ) and that was a torque monster with quite the Dr Jeckyll and Mr Hyde personality too....

Great times!