Results 1 to 3 of 3

Thread: Piston=Bore chart.

  1. #1
    Join Date
    Apr 2009
    Location
    Burlington, IA
    Posts
    92

    Piston=Bore chart.

    Forum is kinda quiet today. I thought I'd ask a question that I couldn't figure out how to search.
    I was thinking...wouldn't it be cool if someone had a chart that showed what overbore piston size=the cc size. And then I thought, surely someone here has that info.

    416, 426, 440 etc...anyone have wiseco numbers? Charts? Anything? Just curious and good info.
    2002 400ex AC nerfs HMF slip on Duncan Racing graphics Pro Tapers Black and Yellow.

  2. #2
    Join Date
    Aug 2008
    Location
    Toledo, Ohio
    Posts
    263
    I was also currious about this and the lt250r. I plan on boring it out very soon and i was wondering what CC it will be at when its all said and done. I know there is a equation like

    bore X bore X stroke X .7854 = (pi * radius^2) * stroke = CC displacement
    1985 LT250r bored .060 over, weisco piston, FMF Pipe and silencer, Maier Plastic, Razr 2 Tires, K&N.

  3. #3
    Join Date
    Apr 2005
    Location
    WI
    Posts
    8,922
    heres the 400ex

    397 - 85mm
    402-85.5mm
    406-86mm
    416-87mm
    426-88mm
    440-89mm

    There you go, not sure what the .5's are since they are just rings for most of them. They are to just clean up the cylinder. These are the common sizes. with a +4mm stroke addition it changes them by 20CC to the better. This is using a hotrods crank. That would make a 440 a 460 with the stroker. and each the same i believe, steve
    2019 Maverick X3 XDS Turbo R
    2003 TRX 400EX
    2016 HONDA RANCHER

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •