Low compression?

Discussion in '2-Stroke Engines' started by brokenvespa, May 10, 2016.

  1. brokenvespa

    brokenvespa New Member

    Hi guys, I am looking for more power. I just used a compression gauge on my bike and it is only reading 40psi. The bike runs and with a 38t sprocket tops out at 25 mph. I have read that stock compression is around 90 lbs. Is it even possible the enginevitable will run at 40psi? I got this bike used and was told that the engine only a couple of tanks of gas run through it , so should be fairly new.

  2. Rob H

    Rob H Member

    I can't believe it runs at all with 40lbs of compression
  3. Rob H

    Rob H Member

    Maybe your gauge is wrong or is leaking that seems very low u need 3 things for combustion fuel fire and compression
  4. FurryOnTheInside

    FurryOnTheInside Well-Known Member

    And air.
    And proper carburetion of that fuel and air.
    But if it really isn't possible to run at all with 40psi compression then the test must be going wrong...
  5. Rob H

    Rob H Member

    Yup something is not right in Denmark
  6. crassius

    crassius Well-Known Member

    are you holding throttle open and turning motor until the gauge stops going up?