rattling engine

Discussion in '2-Stroke Engines' started by beentryin, Jul 12, 2010.

  1. beentryin

    beentryin Member

    ive got a gt5 and have ran about 4 gallons thru it. the motor is starting to sound like theres bb's in the motor rattling.and it only makes the noise when im cruising.with no load on it.the other sound comes when i pull my clutch in it makes a scraping noise.ive check the plate and pads they look normal.and ive always kept a glob of grease on the gears and buck bar.

  2. AussieSteve

    AussieSteve Active Member

    I reckon that a top-end pull down is in order, at the very least. Sounds a lot like you might have a failed bearing.
    Dunno about the clutch noise - we've discussed that.
  3. beentryin

    beentryin Member

    well i tore down the cylinder and pull the piston the wrist pin bearing doesnt look bad.but the rod doesnt have any up and down play but it does twist a little
  4. AussieSteve

    AussieSteve Active Member

    While you're at it, make sure there's no noticeable play in the crankshaft.
    You're sure the gudgeon pin needle bearing is OK?

    I'll have to think some more on this one. There's nothing else in the engine itself to cause your noise.
  5. Clutch is a simple fix, I have had the same issue on my bike Just remove the clutch cover. Below that is the clutch there is a screw that holds the adjusting nut on remove that and use needle nose pliers to turn the adjusting nut try 1/4-1/2 turn at a time replace screw then give it a quick ride (don't really even need to put the cover back on for real quick ride... rince and repeat until the sound goes away.

    The motor: Remove cylinder head (jug) look at rings you could have busted one (unlikely in a short period but possible) also check the cylinder for scoring while your at it. If that is not it remove the piston from the connecting rod by removing the pins and bar through the center of piston now check the bearings in the end of connecting rod make sure they are good. Lastly get a high powered magnet and try and turn the engine (bottom end) upside down use the magnet to pull out and debris that may be inside the case.

    put back together and enjoy .

  6. beentryin

    beentryin Member

    my cylinder is a little scored.but the motor has good power.in the mid range to high.lowend kinda sucks when the motor gets hot or opp. temp
  7. Karryhunt

    Karryhunt Member

    Engine/Clutch Noise

    I have yet to see or hear one of these cheap rice burners that runs quiet or smooth. It's a 2 cycle for crying out loud. They all make noises that make you wonder if something is about to fail. I think a lot of it is caused by backlash in the clutch gear and those little bb's in the plate behind the gear. I shot in some white lube in the 3 holes on the backing plate which helped a little but not much. Don't worry too much about these little rattles, scraps, and groaning you hear.You need only to be concerned about the "big" noise that occurs when your engine seizes or throws a rod or something like that.:ack2: