How To 'Break In' a Two Stroke MUST be done after a top end rebuild

Discussion in 'Engine' started by lbwd, May 18, 2007.

  1. 2k1blastr

    2k1blastr New Member

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    ok...i just bought a motor off of ebay,its rebuilt from top to bottom.its bored over .010 and new everything else.so im assuming this would be the way i should break it in?
    its supposed to arrive at my door step mon. feb13.cant wait.
     
  2. 2k1blastr

    2k1blastr New Member

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    ..and i forgot to include,its been set up for pre-mix.
     
  3. slickerthanyou

    slickerthanyou New Member

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    Bro there are many ways to do it! Most are correct! The first post is a little overkill. My builder says-

     
    Last edited by a moderator: Feb 6, 2014
  4. Blaaster

    Blaaster Moderator Staff Member Technician Forum Supporter

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    I always go a little further, after the heat cycles, re tension the head and jug bolts on a cold motor.

    Ride 2 tanks of fuel at no more than 3/4 throttle at the recommended 32:1 fuel oil mix.

    Then fang it. May be over kill, but been doin it for years, and old habits die hard.
     
  5. Jacobstaggs22

    Jacobstaggs22 New Member

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    I heard letting it idle was bad ? I thought you had to vary the rpms?
     
  6. Blaaster

    Blaaster Moderator Staff Member Technician Forum Supporter

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    Blip the throttle , vary the revs.
     
  7. iLikeIke

    iLikeIke New Member

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    how i always did it was take it easy one the first tank, riding 15 minutes n lettin it cool. after that i had my ways with it partly of being to dam excited with a new motor.

    as long as you dont overheat it or open the throttle wide open in neutral youll be fine. ive heard a lot of people just skipping the break in process

    look at how you break in a v8. start it and right away after checking timing you go to 2500 rpm for a good half hour. granted 2 strokes are different
     
  8. Blaaster

    Blaaster Moderator Staff Member Technician Forum Supporter

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    2 strokes are very different to V8s, you have no cams to break in.
     
  9. 2-strokeManiac

    2-strokeManiac New Member

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    That is deffinatly the right way to do it!
     
  10. davidc

    davidc New Member

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    Need help..were can i get a cheap rebuilt kit for my 94 yamahA blaster 200??
     
  11. CRK91

    CRK91 New Member

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    You go to egay or google and type in cheap rebuild kits and then you will wind up buying 5 or 6 of them. Just go ahead and buy a good kit save yourself a lot of time and money. Me personally I buy wiseco top end kits but if it's crankshaft or bottom end get hot rods. Just my 2 cents
    Good luck
     
  12. Tooloose

    Tooloose Member

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    Do not let a new engine idle, you most continue to blip the throttle under no load conditions, after a brief full choke start up. You continue to do this until engine warms to full operating temperature. Then a complete cool down to ambient temperature. This is the very first , most important step of a new two stroke engine! Then complete this step at least two more times! No Load! No Full throttle for extended periods without the same amount of time to cool for the first 20 hours of operation. This is what Yamaha recommends as a adequate break-in time for the YFS blaster✌️Peace
     

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