Results 1 to 3 of 3
  1. #1
    SJ-(KY)'s Avatar
    Join Date
    Jul 2007
    Location
    Forest Hills,KY
    Posts
    278
    +1
    4

    Squish for flat top Piston raised port combo?????

    Im sure this is gonna be another question for Morris or Jonny ..... Im running a raised port set-up 0.063 shim.. The pistons are stock cut flat-top Pistons.... I know the sweet spot on squish is in 0.060 to 0.065 range for stock pistons... The heads im running have already been cut for this combo but the squish is up around 0.091... Is this normal since its a flat top piston an the squish can only be closed so much??


  2. #2
    jonny5's Avatar
    Join Date
    Aug 2005
    Location
    Redding, CA
    Posts
    1,266
    +1
    5
    Flat tops run lower squish limits than stock.. Like .028ths if I recall what you have it will be very soft and run ...well not great at all.

    Something wrong... Like did you cut the cylinders down. If your raise the bottom of the cylinder with a spacer you have to cut the top of the cylinders down. basically you went up about 1.3mm I think so the top needs to be cut the same amount.

  3. #3
    SJ-(KY)'s Avatar
    Join Date
    Jul 2007
    Location
    Forest Hills,KY
    Posts
    278
    +1
    4
    Thanks a bunch Jonny I appreciate the info... I found that the Base to deck height should be around 5.040 an mine were stock untouched jugs that were 5.086... That alone will put the squish around 0.045 an thats the area I want to start at on 93octane so i can get some feed back on this set-up... My guy that cut my pistons well we'll just say he couldve done a more accurate job an ill leave it at that ;-/.. R u running race gas with your squish 0.028?

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. Fs -Skiworx stage 2 raised port cylinders with wsm flat top pistons
    By mod addict in forum Kawasaki PWC Performance (2-stroke)
    Replies: 4
    Last Post: 08-03-2014, 03:04 PM
  2. FS 4 Ported 1200 GPR cylinders w/flat top pistons
    By KawieGuy in forum Yamaha Classifieds
    Replies: 1
    Last Post: 08-25-2010, 09:38 AM
  3. Whats the deal with 80mm flat top pistons?
    By PolarisNut in forum Yamaha PWC Performance (2-stroke)
    Replies: 9
    Last Post: 09-11-2009, 06:27 PM
  4. WTB- Ultra 150 Flat Top Piston
    By skiguy1028 in forum Kawasaki Classifieds
    Replies: 6
    Last Post: 06-19-2009, 09:08 AM
  5. flat top pistons
    By whiteelvis in forum Yamaha PWC Performance (2-stroke)
    Replies: 4
    Last Post: 03-31-2008, 02:02 PM

Posting Permissions

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