please explain timing in relation to rotation

Discussion in '2-Stroke Engines' started by RMWdave, Jun 7, 2009.

  1. RMWdave

    RMWdave Member

    happy time engines run backwards (in order to run the drive shaft forwards)
    so, if the magneto is turned in the direction of running rotation (clockwise) it is indeed advanced. am i right?

  2. Dave,

    For clarity: the magneto is made up of two components, the coil and frame, and the magnet.

    Looking at the magnet head-on, the more it is rotated on the crankshaft in a clockwise direction the more advanced the timing will be.

    You can also rotate the coil counterclockwise to achieve the same effect.

    The graphic below shows the orientation of the magnet relative to TDC. The degree value is approximate +/- 2 degrees.

    I have advanced the timing on these makes a HUGE differnce in the top end.


    Attached Files:

  3. RMWdave

    RMWdave Member

    your right about that one lol mine got advanced by mistake and now i have to hope i can back it back to where it was!
    thanks alot for the graphic and gettin my question answered. i just hope nothing is gone awry..... its barley broke in and i have ran it with the time all screwed up.... tried to push it. but mostly putt-putted..... thats all i could get out of it was a putt putt.
  4. danlandberg

    danlandberg Member

    I've been wanting to change the timing,(I'm at 5500 f.a.s.l.) In a car, the higher the altitude you need to advance the timing for the best power/performance. This Thing ran GREAT for two days, then it would not idle. I found an in-take leak. I fixed that and now it runs like it did while break in. Plug is gray not tan like I would like. It is not to rich, but I'd like to lean it out a touch. I'm thinking more towards an exhaust problem. (maybe clogged). I've had a lot of 2 stroke dirt bikes, but never messed with them unless they would not run. Not real sure what to try next? ???? Can any body tell me is the out put shaft (drive sprocket) lubricated by fuel oil mixture or is it a sealed bearing? I have not had one tore down this far yet! So I'm not sure of the inner workings. Break down picts are vague.
  5. Heathen

    Heathen Member

    Well if your plug is gray i would say it is running lean, and you need to give it more fuel in the mixture. try raise the needle one or two snaps run it for a few miles to see how it behaves then check the plug to see if it looks better.