AAU spring change and timing chain adjustment

I have a question regarding timing chain adjustment procedure. I need to check my timing chain adjustment , do you need to have the tool to hold the gears in place or could I just use a socket on the cam nut to hold them in place ?
Also , when removing the AAU , is that on a key of some sort to make sure it only goes in one place on the cam ? I read where it's a tapered fit, if so it could be put on in 360 degrees ? That would mess up the timing. I know that I would need to mark the points breaker plate good to avoid timing issues. It just doesn't make sense to me that the AAU could go on in any position as that controls the points.
Thanks for your help.
73 850 MK1

You don't need anything special to adjust the timing chain unless the intermediate gear spindle is loose in the case.
Yes, the AAU will fit in any position. So mark it's position.

Set the crank at 28, then mark the position. If anything moves, set it back to the 28 and reassemble. should be close.
As mentioned, it sits on a taper, it's not keyed.
The manual mentions a slide hammer to remove the AAU, if you don't have one, thread a bolt into it and tap slightly at an angle knock it loose to remove.

It's been awhile but I seem to remember using a rolling paper held in place by the spring tension of the points and slowly turning the motor over until the moment of release. You can use this to verify if your points are opening at the prescribed moment. Now, whether your timing gauge inside the primary is accurate is another can of worms. However, if you feel that the points are opening in the correct spot now, then you could use the paper to see when it releases and check this against the scale to duplicate it. This procedure might even be in the manual!

rvich said:

It's been awhile but I seem to remember using a rolling paper held in place by the spring tension of the points and slowly turning the motor over until the moment of release. You can use this to verify if your points are opening at the prescribed moment. Now, whether your timing gauge inside the primary is accurate is another can of worms. However, if you feel that the points are opening in the correct spot now, then you could use the paper to see when it releases and check this against the scale to duplicate it. This procedure might even be in the manual!

Click to expand...

...And the AAU must be locked/held fully advanced whilst doing so.

PS if you are doing ignition timing on a K2F mag, check other cyl also to verify mag fires 0 + 180 degrees!!!!

WHY the itermediate gear spindle gets loose IS because SOMBODY turns the engine over Via the TIMING CHAIN . !

So cunning swine put the motorcycle on the beer crate . Probly unavaliable in these ' progressive ' times .
So the Mainstand , blocks . Paddock Stand etc .

REMOVE THE PLUGS ( So she swings through wuderbar. ) Put In Second Gear ! . NOW the back wheel
is your marvelous lever . A lotta back lash , gotta use it as a fly wheel / slide hammer to a degree .To finnesse crank posn.
Almost need to be astride aft to pull through one crank turn .

CONTACT BREAKERS - The Olde Ciggarette paper Trick . at 30 degrees ignore the thickness . at 28 alow a iota
degreeally .Now the ADVANTAGE of this , is as you , with a wee ring spanner on the A.A. nut , get it to ' click '
( which it does ) on the stop , fully advanced - the paper ( strip ) will JUST come free .
So one can get a degree of finesse / accuracy unbeknown to most .

Ignition On , then , same treatment , youll get the click of the L . T. Spark ,
same pressure on wee spanner Oz. In. Ea Cylinder .9 Point Opening Spark . )

if you cock it up 360/180 degrees , Swap the plug leads ( or coil L.T. ) side to side. For Now .

Use one Cyl. as a Datum , in regard to that . easier with valve covers off .

NO TURNING IT THROUGH OR LOOSENING NUTS WITH THE CAM CHAIN AS RESTRAINT .

The last person who tried that hasnt been seen again .

As for HEAVIER A adv spings , Tames it low down . But may give
' two stage ' powerband . wide Open below three o.k. but afterburners light around 3.200 . With Full Advance home at 3.000 .

Hadvantages & dishadvantages .

theyre standard LUCAS , so Hillman Hunters etc et all for provision ,
would allow a degree of fine toonin .

L.A.B. said:

...And the AAU must be locked/held fully advanced whilst doing so.

Click to expand...

Good save L.A.B.!

Thanks everyone for helping out