Results 1 to 6 of 6
  1. #1

    cylinder & piston sizes

    OK the manual calls for .004-.008" clearance between the piston&cylinder on my 95 sl750 i have .009" using feeler gauges as recomended.

    Question is what should a .5mm over piston and cylinder measure. im trying to figure if the piston and/or cylinder is worn.

    thanks guys

  2. #2
    She likes the bike. But the ski gets her wet!!!! xlint89's Avatar
    Join Date
    Oct 2006
    Cleveland OH
    First, if you're out of servicable specs, it's worn. If you're looking to go OverSized, why not use .25mm first?

  3. #3
    sorry didnt say , its already .5mm over. I know its worn but id like to know wich of the two (piston/cylinder) is worn , and by how much.

  4. #4
    i did find some useful information / piston sizes as follows

    Standard size is 69.75mm

    Sizes available: .25(.010), .50(.020),.75(.030), 1mm(.040)

  5. #5
    ph2ocraft's Avatar
    Join Date
    Apr 2006
    Campbell, Ca.
    hedge, you can take it all the way up to 72mm with Wiseco 2.25 oversize.
    Your .50 was probably bored around 70.25 and you can certainly move up to anything inbetween. You next move you could make is 1.00 over or 70.75.
    Here's the link to Wiseco, for their sizes and kits available.

  6. #6
    Watcon's Avatar
    Join Date
    Oct 2005
    Seattle WA


    An average cylinder should have approx .005" clearance when fresh, and .009" is at the end of the bore clearance.

    a feeler gauge is a rough estimate of your bore clearance, but gets you close.

    The larger the piston, the more bore clearance is needed.

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. '88 JS550 cylinder bore/piston size
    By calvin650 in forum Kawasaki PWC Performance (2-stroke)
    Replies: 0
    Last Post: 05-10-2014, 08:07 PM
  2. WTB STD Size 1200 cylinder and piston
    By Joe Stang in forum Yamaha Classifieds
    Replies: 1
    Last Post: 08-17-2010, 01:11 PM
  3. 66v piston sizes
    By billy's gpr in forum Yamaha PWC Performance (2-stroke)
    Replies: 10
    Last Post: 10-10-2007, 12:31 AM
  4. 1300 oem piston sizes
    By Duke in forum Yamaha PWC Performance (2-stroke)
    Replies: 16
    Last Post: 08-03-2007, 07:23 PM
  5. Piston size
    By CanadianGPR in forum Yamaha PWC Performance (2-stroke)
    Replies: 9
    Last Post: 02-11-2007, 06:02 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