1966 N15cs

Gilesy

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So, after a years delay I am finally putting this bike together. Can anyone tell me how to tighten the magneto taper bolt without moving the timing please. I have it timed to 29deg but I'm not convinced AAU is really tight on the taper. Mag has been re conditioned but AAU seems a bit stiff, chain is not tight, is this because mag is 'tight' from refurb? Not used to magnetos, Atlas and Commando both had EI when I got them.
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texasSlick

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I simply press the AAU onto the taper when I think I have it set right, then finger tighten the bolt. Then I check the timing on both ramps, and if right on, I fully tighten the bolt.

If I had any doubt that it shifted, I would simply check the timing on both ramps again.

Refer to:

Slick
 

Gilesy

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Thanks Slick, I've read your excellent guide. Timing the same on both ramps and is still at 29 degrees, I'm just not confident that AAU is secure on taper. What is the function of the thin disc with 2 holes in it that locate on the 2 pegs on the AAU?
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texasSlick

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@Gilesy:

I do not know the function of that disc. It is possibly meant to be an oil slinger.

As far as confidence that the AAU is secure on the taper ..... if you try to remove it, does it offer resistance to the self extracting bolt? Or, if your self extracting bolt is stripped, do you require a gear puller to get it off? If yes to either question, I would be confident the AAU is properly seated on the taper. OTH, if it simply falls loose, you have a problem.

Slick
 
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I think the purpose of the disc with the 2 holes in it is to keep the C shaped washer that should be there under the bolt head centered when tightening down the advance unit. Otherwise, I don't know what it does either. I'm not a Norton restorer or historian though.

As long as you didn't polish the tapered shaft and inside of the taper in the advance unit to a mirror finish I would not worry about it moving on the taper once tightened down.

I would make sure the advance unit alone wasn't stiff before tightening it down. The internals of the magneto are very stiff on mine, but it has been boxed up for 30 years. I just checked it. I couldn't turn the shaft with my fingers. Not 18 years old with hands of steel anymore. I doubt the motor will have any trouble turning the magneto.

Good luck with the build.
 
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[QUOTE="Schwany, post: 488392, member: I just checked it. I couldn't turn the shaft with my fingers. Not 18 years old with hands of steel anymore. I doubt the motor will have any trouble turning the magneto.
[/QUOTE]
Careful if the magneto bearings are nacked then . . . . .
 
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Bernhard,
The sky is always falling with you. :)

I just went out and turned the damn shaft on the magneto with my fingers, because I knew nothing was wrong with it. It has not been spun for 30 years, and it was rebuilt before I used it. It worked fine then, and was working fine before I removed it. I did have to summon the hands of steal gods for a second to turn it, but it spins easily now with my old man fingers. I thought about attaching the spark plug leads to my balls, but figured it wouldn't do me much good if I couldn't spin it fast enough with my fingers.

The OP had his rebuilt (reconditioned) and it is stiff. Hopefully, the people doing Norton work (in this case rebuilding a Lucas magneto) for money know what they are doing today like they did 46 years ago when mine was rebuilt.
 
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I have imported bikes from your hot country, and without exception all the wheel bearing grease had solidified with the heat. Unless it was done very recently, its fair to say the mag bearing grease has gone the same way.
 

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