1. 2 Stroke Husqvarna Motorcycles Made In Italy - About 1989 to 2014
     WR = 2st Enduro & CR = 2st Cross

250-500cc 2 stroke engine noise?

Discussion in '2 Stroke' started by letitsnow, Feb 28, 2010.

  1. letitsnow Husqvarna
    AA Class

    Location:
    mn
    Husqvarna Motorcycle:
    FC250
    Other Motorcycles:
    CBR600F4
    I have a 2000 WR250. For as long as I can remember, the motor has made some funny rattling noises in the midrange. It doesn't make this rattling noise in the lower or higher rpms, only the middle.

    Every now and then I become paranoid and think that it is piston slap, but I never take it apart to investigate. The motor had 190psi of compression when I bought the bike, and over a year later it has only dropped down to 187psi. If this is piston slap that I am hearing, wouldn't I hear it throughout the entire rpm range???

    I suspect that it is just something else that is rattling due to the vibration at a certain rpm, but wonder what you people think.
    letitsnow, Feb 28, 2010
    #1

  2. Rusty 2 Husqvarna
    A Class

    Location:
    Ashland, KY
    Possibly,...my KTMs both have a horrible sounding chain slap at just a certain loading. Sounds like the top end is flying apart!

    Are you quite certain it isn't a lean ping in the mid-range? That would be my concern.
    Rusty 2, Feb 28, 2010
    #2

  3. HuskyDude Moderator

    Location:
    BC, Canada
    Husqvarna Motorcycle:
    13/TR650
    Other Motorcycles:
    10/EC300, 76/TY175
    Geez that's loaded question.:excuseme:
    Can you get the bike to make the noise while not moving? Doesn't necessarily mean it's coming from your engine. Eliminate the obvious first. Run the bike until you hear the rattle and grab your front and back brakes. That might be all it takes. If not have someone else run the bike till you hear the rattle. Then you're going to have to do some detective work.
    Start grabbing everything that is attached to your bike making sure it's tight. Skid plate, levers, exhaust pipe (do this with a small piece of wood so you don't burn yourself), engine mounting bolts...etc
    If you have eliminated everything on the bike and you're sure it's the engine. Well that's a whole new ball game.
    Does the noise go away with clutch in?
    HuskyDude, Feb 28, 2010
    #3

  4. razornpc Husqvarna
    AA Class

    Location:
    iowa
    chain slap?
    razornpc, Feb 28, 2010
    #4

  5. MOTORHEAD Husqvarna
    Pro Class

    Location:
    Mount Vernon, Indiana
    Husqvarna Motorcycle:
    none
    Other Motorcycles:
    2014 YAMAHA YZ250
    I'd say it's a lean spot and you're hearing some detonation or ping. Is it almost like a buzz?
    MOTORHEAD, Feb 28, 2010
    #5

  6. letitsnow Husqvarna
    AA Class

    Location:
    mn
    Husqvarna Motorcycle:
    FC250
    Other Motorcycles:
    CBR600F4
    Thanks guys, I think that I've just found the source - The junction between the pipe and silencer... There is some play between the 2 and the silencer was bouncing around in there. When I hold my hand on the junction while riding, the noise stops. :thumbsup:
    letitsnow, Feb 28, 2010
    #6