something to think about

Discussion in 'Heads and Cylinders' started by crassius, Nov 17, 2016.

  1. crassius

    crassius Active Member

    Joined:
    Sep 30, 2012
    Messages:
    3,202
    Likes Received:
    10
    got new 40mm stroke motors

    got 2 thick base gaskets so port map at TDC remains same (until it moves a bit & then # of degrees timing changes)

    better or not to put 1 thick base gasket & add 1 thicker head gasket to give 1mm greater closure at both top and bottom

    better or not to put a thin base gasket & add 2 thicker head gasket to give same port map at BDC
     
  2. Venice Motor Bikes

    Venice Motor Bikes Custom Builder / Dealer/Los Angeles

    Joined:
    Mar 20, 2008
    Messages:
    6,149
    Likes Received:
    3
    You should try using just one stock base & head gasket first.

    I've built several racing engines with 42mm cranks that didn't require any extra gaskets... (& this will give you higher compression). ;)
     
  3. crassius

    crassius Active Member

    Joined:
    Sep 30, 2012
    Messages:
    3,202
    Likes Received:
    10
    done that with the thick head gaskets back in the H2 motor days - if I still had a dyno, I'd try them all, but lacking good measurement of result, I'll just stick with what I have unless I see a need to experiment

    got 2 of the new motors up on test bikes and won't offer them for sale until I see how they compare to each other, as that seems a good way to check factory tolerances - I believe they are both a bit better than the ones I had tho
     

Share This Page