What is a Electronic Advance?

[LarryA_Texas]

mechanical advance

What you are looking for is really easy to install. Once you take the cover off you'll see the signal generator in place with three screws holding it. That's the part the dyna will replace. If you have a 1982 or earlier the mechanical advance is already there. '83 and later there isn't one. (I think) The way to tell is to look at the signal generator. If it has 2 wires you have a mechanical advance. Just unscrew and pull off the signal generator. If it has 4 wires go shopping; you're going to need the mechanical advance.

In the center is a 19mm bolt and in the middle of that is a smaller 12mm bolt. with both wrenches in place loosen the 12mm and use the 19mm to keep the shaft from turning. Once the 12mm bolt is out, if only one thing comes out you need a mechanical advance. If two things come out, and the second one has springs on it, that's the mechanical advance. The part that came off first spins around and triggers the coils in the signal generator. The dyna will have a black plastic cylinder that will replace it and a washer to hold it in place. Bolt it on, screw the dyna in place and follow instructions for the wires.

Piece of cake.

[Nessism]

Just took this photo of my 1982 GS850. Note: this is the second generation electronic ignition with ELECTRONIC ADVANCE. To install a Dyna ignition in a 1982 or later 850, a mechanical advance unit from a 1979-1981 bike is needed.

[psyguy]

, if only one thing comes out you need a mechanical advance. If two things come out, and the second one has springs on it, that's the mechanical advance.

larry, i absolutely love this piece of "how-to" 8-[
cheers