monster engine carb tuning help

Discussion in '2-Stroke Engines' started by rattlerviper, Mar 30, 2011.

  1. rattlerviper

    rattlerviper New Member

    My monster engine has been a reliable powerful beast up till now (it's on a bmp friction drive). My fuel filter broke and the carb got dirtied up. I got a new filter took the carb off and cleaned the little bugger...I forgot to check where the mixture screw was set before I removed it. Suffice it to say now I can't get it right, I've even had a buddy who is a auto mechanic look at it. Nothing wrong with it (he even stripped the carb down again and recleaned it) but we can't figure out where to set the screw.

    Do you guys have any advice on how to set the mixture screw on this thing? Thanks everyone.

  2. rattlerviper

    rattlerviper New Member

    Ok i have it close now. It is bogging down under full throttle, does that mean its running rich?
  3. adb140275

    adb140275 Member

    if it is running real smooth (too smooth) and sounds like BRRRRRRRRRRRAAAAHHH (bogging), its too lean

    if it sounds like is misfiring, or is running real choppy, then its too rich.
  4. DanielMaia

    DanielMaia Member

    By your symptom (boogg at WOT), its lean. Increase the gas ratio (more gas to the same air), and when you hear the engine revv with no hesitation, thats the good spot ;)
  5. rattlerviper

    rattlerviper New Member

    Alright thanks guys. I have it so it seems like it is running well. Nice tan spark plug. Now to keep it running i have to set the idle too high so the clutch is just starting to engage. Any ideas what i may be doing wrong?