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This is in response to a specific question regarding the '69 automatic advance ignition, but it's got enough info to apply to all points timing setups (and it's got '70 and later info too)....so I am copying it here, into the biker basics area...if you wish, feel free to cut and paste the entire post into your own computer as a Word or text document:

Pull the cover...see the points cam? Grab it with your big ol' fingers (use a needle nose if ya' can't get a grip with the fingers) and give it a twist ...it should twist clockwise on the '69 and earlier automatic advance (later models twist the opposite way, but I'll get into that at the end of this post) and snap back when ya' release it. That's the "automatic" advance. See the two nuts on the base plate the points and condenser are mounted to? If ya' pull those two nuts, you can remove the entire base plate off the distributor and you'll see the advance weights. The weights need to be lubed now and again, where they mount on the pins. And ya' need to replace the little springs now and again too. Ya' can't get new weights for the early models before '70 (not that I am aware of anyway, and I've been looking) but you can get the springs. The weights need to be free to move out and advance the timing when the motor gets up above 1500 - 2000 rpm and the springs need to keep 'em snapping back when the rpms drop...."automatically", get it?

As far as timing goes, I actually prefer to static time the old motors...you can use a timing light and I'll explain how, but given the choice I'll stick with static timing...I've done plenty both ways and I trust the results of static timing if it's done properly in the full advance position.

First, ya' gotta' make sure the advance assembly is in decent shape and working properly. Make sure the points cam is referenced correctly (it's held on the end of the distributor shaft with a little clip and on the early (pre-70) big twins it's possible to put it on 180 degrees out...on the '70 and later models it only fits one way). It must be installed so the smaller lobe is set to open the points when the front cylinder is coming up on it's compression stroke. If you aren't sure when the front cylinder is coming up on compression, remove the front intake valve pushrod cover and watch that lifter. When the front intake valve lifter goes up and then comes down, start looking for timing mark in the hole...the piston is coming up on it's compression stroke when that valve lifter goes down (valve closes). Then, put the base plate back on and set the point gap. On that early bike (69 and earlier), you want to gap the points at .020", on the later bikes, set to .018". Set the gap with the points block on the highest part of the points cam. Once the gap is set, you can static time it. Remove the timing plug on the primary side of the case. Roll the motor over until the front cylinder is coming up on a compression stroke and look for the front cylinder advance timing mark ( on the pre-1980's big twins it's a vertical line in the flywheel - more on the other models later). Set that line so it is between the back edge and middle of the timing hole (if the gas in your neighborhood sucks and you've got a high compression motor, set it in the middle).

Now, connect a 12 volt test lamp or a dc voltmeter with the negative lead to a good ground on the bike and the positive lead to wire connected to the points (you can connect it to the coil terminal that points wire goes to if it's easier for you). Keep in mind, when the points are OPEN the test lamp will light or the meter will register 12 volts. Turn on the ignition key. Loosen the little clamp at the base of the distributor that locks it in place. To start the static timing process, the points need to be closed. If they are open, turn the whole distributor clockwise until the points are closed and the test lamp goes out (or meter registers 0 volts).

OK, now you're ready...this is just a little teensy bit tricky. What you need to do is turn the points cam clockwise to their fully advance position and hold 'em there (sometimes it helps to have a friend hold 'em, but you can do it all by your lonesome, just practice). Once the point cam is twisted to its fully advance position, you want to points to be set to where they are just beginning to open the points. Turn the distributor base counter-clockwise until the points rubbing block just makes contact with the points cam...the very second the test lamp comes on (or the meter registers 12 volts) STOP!!.

That's what you want...lock the distributor down. To check it, turn the points cam to its fully advanced position and when it stops the lamp should just come on...the points should be barely open...you should be able to just touch the points with your fingertip and make the lamp go out. It may take you a couple of tries to get it exact the first time, but with practice you'll find it only takes a few minutes for the entire process.

Now that you've static timed it, you can check it with a timing light if you wish. You MUST use the clear plastic plug or the "hose" trick described here. Use a timing light with an "inductive" pick up (that's the thingy that clamps on the sparkplug wire and triggers the timing light flash). Simply connect the timing light to it's power supply (usually the motorcycle battery), put the inductive clamp on a plug wire (since early HD's fire both plugs all the time, it doesn't matter at all if ya' use the front or rear plug wire for this, but you really should get in the practice of using the front plug wire, since if ya' use a timing light on a later model with a true single-fire ignition, it will matter). Once ya' have the timing light hooked up, fire up the motor (watch the timing wires, keep 'em off those hot pipes!!). Run the motor up to a little over 2000 rpm and keep it there (a throttle lock screw comes in handy for this!!). Point the timing light into the timing hole and pull the trigger. When the light flashes, you should see the advance timing mark in the hole. If it ain't there, your timing is off and you'll need to turn the distributor a little one way or the other until ya' see the mark in the hole as described in the preceding paragraph. It really, really comes in handy to have a trustworthy friend helping with this, since the timing mark is on one side of the bike and the distributor is on the other...

Anyway, that's a full explanation of timing a early HD. Too tell the truth, this method also applies to the "manual retard" distributor, but ya' skip the part related to "automatic" advance assembly inspection and you also skip the part where ya' twist the points cam to the advanced position. With the earlier manual advance distributor, ya' just turn the entire distributor to its fully advanced position and set the timing there.

And surprisingly enough, this basic explanation pretty much covers the later "cone motor" timing on the points setups used starting in 1970. The big difference with those is the points assembly is built into the cam cover. Since they're in a recess, it's kinda' hard to get in there to turn the points cam to the full advance position (by the way, the early distributor shaft runs clockwise and turning the points base plate counterclockwise will advance the timing...it's the exact opposite starting in '70...the points cam turns counterclockwise and turning the points plate clockwise will advance the timing)...anyway, it's hard to get in there and grab the points cam, but there's an easy trick to do. There is a special tool for turning the points cam and it works great, but you don't need it if ya' do this trick. Take out the points plate. Drill a 3/8" hole in the points plate at an approximately 7 o'clock position....center the hole between the outer edge of the plate and OD of the big hole in the middle of the plate. Now, put it all back in the motor. Turn the motor over and look in that hole ya' just drilled. See the advance assembly going past that hole? See how easy it is to squirt a little teflon lube (NEVER GRAPHITE!!) on to the advance weight posts through that hole so you can keep 'em lubed? Now that you've got the hole there, set the front cylinder advance mark in the center of the timing hole....then use an awl or small screw driver to reach in through that hole and pry the weight outward into the advance position...now static time the points. And don't forget, the '70 and later points are gapped at .018!! (.020" is for the '69 and earlier single points). And while we're speaking about timing marks...the early bikes before late '80 all use a single vertical line in the flywheel for the front cylinder advance mark (7/16" before top center)...starting around '70 HD also included a TDC mark on the flywheel, which is a small drilled dot that shows up near the bottom of the timing hole when ya' look in at the flywheel. In the most stupid move ever made by the HD Motor Company, during late '80 they swapped the marks!! After late '80 the vertical line becomes the TDC mark and a small drilled dot that shows near the top of the timing hole becomes the advance mark! Are they idiots or what??? The line worked fine for over 7 decades...and then they move it??? Anyway, the methods described above all refer to the front cylinder advance timing mark...be sure which mark is on your flywheels when you are starting this procedure. If you just don't know which mark is which, try this trick: Take out the front spark plug. Pull the front intake valve pushrod cover. Roll the motor and watch the intake lifter. Let it open the valve (goes up) and then close (goes down). When it goes down, stop. The piston is coming up on a compression stroke. Take a standard plastic drinking straw (yes, a drinking straw) and drop it down the plug hole so one end is sitting on the top of the piston and the other end is sticking out of the plug hole. Slowly roll the motor over until the straw doesn't come up any farther...you're looking for top dead center. When ya' find that point, make a mark on the straw even with the top of the spark plug hole. Pull the straw out and make another mark, exactly 7/16" inch above the first mark you made. Now start over, but this time, when the new 7/16" mark you made is even with the top of the spark plug hole, stop!! Look in the timing hole...you should see the advance mark, which will be in the hole when the piston is at 7/16" before top center. This is for big twins. Sporties are almost the same, but their advance is set at 11/16" before top center.

And now that I've explained all of this, I have one more thing to say. It really ain't a distributor, even though most folks call it that. I call it that here because I didn't want to confuse you. It's really an ignition circuit breaker assembly. Just want you to know, in case ya' ever get on Jeopardy and it's the bonus question