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"Homebuilt" expansion chamber

Discussion in '2 smokers' started by dorkpunch, Jan 28, 2011.

  1. Lutz

    Lutz Fuzzy Rabbit

    Jul 17, 2010
    North Shore of Lake Superior
    ATC250R...cool! 250R/Rotax hybrid? Even cooler! Where can we find out more about that build?

    Just looked through the smugmug pics. wow! Gotta know more.:ear
  2. BillyGoat4130

    BillyGoat4130 Been here awhile Supporter

    Oct 19, 2014
    Live Oak, FL
    I contemplated starting a build thread here - I still may because this is going to end up in 2 major stages basically. Building the motor, and then putting it in a road chassis of some sort, like Ted's Frank bike http://advrider.com/forums/showthread.php?t=863803

    Motor is about 85% done at this point. Now that the pipe is done I only have a few things to button up before I start being new case bearings, seals, crank, etc and start setting final deck heights and such.

    One the pipe, I used the 2 stroke exhaust wizard from build and click. I then had to learn a little hand math to figure out how to divide up everything into sections (and how long to make each section, and to know what the entry/exit diameters were on each section). After that I used cone layout to maker a 2d .dxf file that I sent to a buddy with a hook up on laser cutting, that also enabled each section to be labeled which was a God send. I can't imagine having to had kept up with these things otherwise.