Lv 4
Adam asked in Cars & TransportationMotorcycles · 1 decade ago

Setting The Points On An Old '79 Suzuki GS850 Motorcycle?

I almost have it down but can't quite fine tune the points enough to actually say it's in time. The timing was so close it could be rode (near perfect) but there was still a pretty significant "stutter" that concerns me. Not enough of a stutter to cause any major probs.

Now there are 2 points that have to be set individually. Cylinders 1-4 & 2-3. There's certain marks on the ATU that have to correspond with the opening and closing of each point. It's kinda like | T | F 1-4| & | T | F 2-3| now this symbol " | " is the mark that's gotta be aligned with the "stationary mark." Which one of those 3 marks am I shooting for? 1st, middle, or last. Now depending on how you look at it will determine the order of the marks. It rotates clockwise which will cause the marks to come around backwards. I'm reading 1st, 2nd, and 3rd from left to right. Now if someone knows of some tip that would be fantastic!

3 Answers

  • G B
    Lv 6
    1 decade ago
    Best Answer

    Firecracker has given you the correct information, but, I'll add to it. The best way to do the timing is with a timing light. At idle speed The vertical line near the F mark is supposed to line up, once you get there you can slowly rev it up to check if it is advancing correctly. If it is you will see the double II vertical lines move under the indicator. If you have to make adjustments try using the point gap, smaller gap retards, bigger gap advances, its pretty touchy, if you see them move you probably have gone too far. Try to avoid turning the timing plate as it will throw your point gaps way off.

    Source(s): Bike mechanic since 1980
  • 1 decade ago

    Timing light or volt meter. Its not mad science. As the points open is when it fires. so when it comes around to "Mark" the points should

    be just cracking open. Or call your local dealer and set it by gap.

    Find out what the gap setting is and get a feeler guage and that

    should bring you in close enough. You can pull the plug on cyl 1

    to see if its at top dead with a long screw driver or a pick. Don't push the start button to do this. And don't try to turn the crank from the timing side. If you have never done this be for I advise to find a friend

    that has. You can do damage if not careful. Good luck.

  • 1 decade ago

    The marks you want are the vertical lines.

    T = top dead center.

    F = fire.

    Use the vertical mark next to the letter F.

    1-4 should show below the F.

    When setting the other set, 2-3 should show below it's F.

    Use an initial gap of 0.3-0.4mm (.012-.016in).

    Source(s): Twins. The fours had the same marking system.
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