Engine Trouble clanking noise coming from the engine

Discussion in '2-Stroke Engines' started by kyman, Nov 2, 2011.

  1. kyman

    kyman New Member

    when i am going full speed a metal clanking noise is coming from the engine. the noise gets louder as the rpms go up.

  2. willfargo

    willfargo Member

    Likely to be the gears, you can grab some engine noise dampers from SickBikeParts
  3. FelipeCobu

    FelipeCobu Member

    How old is the engine?

    You can remove the magneto cap and the spark plug and turn it by hand, to check where the noise come from.

    You can also remove the header and jug and check the connection rod and piston pin.

    Felipe Cobu
  4. ddesens

    ddesens Member

    Dont run it anymore till you find the problem. You dont want to do more damage.
  5. blue 48

    blue 48 Member

    my chain does that when the rear wheel bearing gets loose:ack2: could be that possibly, dunno keep us posted:)
  6. motorpsycho

    motorpsycho Active Member

    I don't know about that.
    if there is a clanking / knocking noise, more than likey if there is damage, it's already been done.
    these engines are cheap enough to replace when they fail.
    I'd judt ride it until it won't go anymore, and then just replace the entire engine.
    BUT, that's just me and my opinion.
  7. Al.Fisherman

    Al.Fisherman Active Member

    I agree, but I would check the magnet, drive gear, the large and small clutch gears. It may be one of those rubbing (tattle tale rubs on the covers). Also might be the bearings in the clutch itself (one of those what? 57 bearings). There is a member in one of the forums I was trying to help on the phone...long story cut short, we found he had dropped a acorn head nut into the engine. Actually it could be a number of other things...are you capable of tearing a engine down should you need to?

    You may ask, who was that?...don't, I'll never tell. :>)
    Last edited: Nov 5, 2011
  8. bideronit13

    bideronit13 Member

    I've read on other posts that with these engines there's a piston rattle noise that happens quite often when at top speeds.
    Well depending on how loud the noise is I would'nt worry about it if its not to loud.
  9. HeadSmess

    HeadSmess Well-Known Member

    last clunking rattle i had happened to be my top piston ring :( stupid locating pins that come out and put dirty big gouges in otherwise miraculously perfect cylinders!

    surprised the ring didnt chew out threw a port... just chamfered the edges nice and behaved itself. was running fine when i stripped it to make another mod...

    waste of a cylinder and piston. and the mods i made. i give up. i just replace at the first hint of trouble now. no more rebuilds! stupid bleeding junk motors.
  10. wan37

    wan37 Member

    I have a 48cc sky hawk GT2B and at idle the gears are tapping the gear case.I put my hand on the outside gear cover and it stops.So should I open it up and see whats causing it or let it be.
  11. Joeeastman

    Joeeastman New Member

    I had a similar problem and it was the 3 prongs coming off the large clutch gear making contact with the clutch cover, i made a gasket out of some thicker gasket material and got the needed clearance, seemed to have worked. You can take the cover off and run the bike up and down the road to see if you still have the noise and if not, then there is the culprit......hope that helps.

  12. wan37

    wan37 Member

    I took it the gear cover off and the screw that supose to go on the small bevel gear came off and was hitting the cover,no other damage was lucky, fixed it.