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I'm going with door number 2

It's getting closer!!!

Interested in the brass knuckles....

I'm looking foward to getting my hands on them I almost feel like assembling it then rip it down to port it so I can see diffrence

I said that not all predetonation is audible. What I mean by that is that the rider would not necessarily be able to hear "knock" at low levels and by the time the rider can hear and diagnose the "knock" the engine has been predetonating for quite some time. Possibly to the detriment of the engine. An improperly designed head can predetonate and hammer away at the big end and small end bearing forever and barely be audible outside of the engine. Doesn't mean it can't damage the rotating components. Install a knock sensor on the side of the motor and THEN test for predetonation if one should choose to "experiment" their way to hard squish numbers. However, I caution against that too, as soon as you have hard squish data numbers and change one parameter you are no longer perfectly optimized again. The lesson to take away from this post is that specific numbers are only specific for a specific build. More general numbers are slightly less powerful (still significantly more so than factory heads) but also "safer" for more conditions and mishaps. Also, it's easier to discuss and understand if we all get on the same page about the process of design and building of a rechambered head. It was suggested I include some more information (all of which is true and relavent!) Number one is that the faster, more energetic charge burns faster. This has the same basic (flame hits the piston earlier) effect as advanced ignition timing. Igniting a lazy charge early and igniting a really excited charge later end up at the same point. Generally, there is less (or even no need at all) need to run advanced ignition timing with a rechambered head. Second thing is that the value (increased charge speed) diminishes somewhat with increased compression. At some theoretical point, the compression will be so high, that the squish area isn't "exciting" the charge any more than it would be naturally using the higher compression. This limit, I don't believe, is applicable to air cooled singles as heat and fuel choice is the limiting factor on these engines anyway, but an interesting note none the less. Some er...... light reading on the subjects (and many many more). SOME of the data, theories, and methods used are slightly outdated (engine's designed in the 60's and built in the 70's) but generally it still applies in theory and concept! A reference of books: Design and Simulation of 2 Stroke Engines, Gorden P Blair 1996 Basic design of the Two Stroke Engine, Gorden P Blair 1990 Two-Stroke Tuner's Handbook, Gordon Jennings, 1973 Two Stroke Performance Tuning, Alexander Graham Bell, 1999 The High Performance Two Stroke Engine, John Dixon, 2005