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Discussion Starter #1
This is a bit of an offshoot of the pod thread which seems to have been solved (for now). your info about tuned intake got me looking around for more info, and i thought it maight not hurt to ask some questions here. even if i only have more answers to look for that is ok too. So a particular site i found mentioned that for tuned exhaust length, the speed of sound was used in conjunction with exhaust temp in their formulae for exhaust length. What about intake? the speed/pressure of ambient atmosphere and temp of ambient atmosphere? Probably more like the speed of the spent gasses traveling out of the cyl in conjunction with capacity of the cyl, huh? i know im missing stuff, feel free to school me...
 

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Phil Irvings Tuning for Speed

Alexander Campbell's Four Stroke Tuning In Theory and Practice

David Vizard stuff is all good and he posts on some of the Mini sites

then poke about on The Old One's site

the ambient temp and atmospheric pressure are both variables that do indeed affect general tuning

but for fabricating your basic setup sans electronic or unreasonable mechanical sophistication

really aren't in the running for basic design considerations
 

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Just as a follow on - I did read a CW article about one Italian bike maker that indeed had considered intake lengths and had some computer control to increase or decrease the intake length on the fly. BTW - the bike cost more than my house. I guess if your going to be at that end of the spectrum, anything is possible.
 

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Discussion Starter #6
That calculator sure takes some of the fun out of it but helpful, im sure. yeah the variable length intake runners are already available from a couple of manufacturers. I remember the story about the MV's that made use of it but i believe yamaha is doing the same thing now on their R1's and maybe R6's. crazy
 

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for under 13K you can buy a new GSXR1000 that has this same technology and does so with really amazing results

I must say the 06 I put several miles on had the most amazing 4 stroke engine I've ever straddled

in fact you can get a gently used 07 for less than 6g's

I think some of the other UJM sport bikes have it as well

even variable volume exhausts


also the better intake calculators take the rod to stoke ratio as well as port length and volume

but that one will work just fine
 

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whoa . .. . I guess I've been on this board too long. Topics are re-surfacing . . ..
 

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adiabatic and inertial force feeding/ supercharging rocks

the first setup is primary secondary progressive spread bore with the intake split horizontally to both cylinders

both setups run ice cold
 

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That's about as old school as you can get. Ok - show pictures of the bike that's in the background.
 

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okie dokie

these have been around for years and don't quite see them leaving anytime soon

I kinda get attached to them but a guy stopped by today and came close to buying this one
 

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oh and that is me in the black shorts

don't any of you dare make any smart comments about how the bike makes my azz look big
 
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