69 Commando Timing ?

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Rondo

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I recently picked up a 69 Commando in a rolling "unfinished rebuild" condition, engine totally assembled, partially wired.
I have adjusted valves and points now I'm attempting to static time. On the left cylinder I validated the correct stroke with both intake and exhaust valves closed (loose rockers) then backed up to 28 degrees on primary indicator. Cam is in the fully advanced position (all the way and locked down in the counterclockwise position)
There is not enough adjustment in the timing plate or secondary adjustment plate to open the corresponding points, close to the lobe but wont make it?
Am I doing something wrong?
Is there any way the timing advance unit could be installed wrong, not familiar with the inside workings?
Not sure if the contact breaker plate were installed 180 degrees if that would make any difference?
Any help would be very much appreciated.
 
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Is the engine a 20M3 or 20M3S? both were used in 69 and the engine configuration and ignition have quite significant differences? Makes it hard to help...
Body style Fastback-"R"- or "S" helps too ...
 
Look at your engine number, it will start 20M3 and either have an S or not followed by numbers. Are your points on the upper right of the timing cover on the outside of on the left behind the timing cover on the crankcase.
 
Rondo said:
There is not enough adjustment in the timing plate or secondary adjustment plate to open the corresponding points, close to the lobe but wont make it?
Am I doing something wrong?
Is there any way the timing advance unit could be installed wrong, not familiar with the inside workings?
Click to expand...

Whether it is 20M3 (points in the housing beind the cylinder) or 20M3S (camshaft points, Roadsters should be 20M3S but a Roadster should not be '69) as you have run out of slot/plate adjustment then the auto advance (which is not pegged) needs to be removed and repositioned, either advanced or retarded as necessary to bring the timing back within the adjustment range of the timing and secondary adjustment plates.
 
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Thank you for the responses, I do not see an engine number on the block where it is on the other two Nortons I picked up (73 & 75). Maybe on 69's it in another location? The frame and transmission are matching. I call it a roadster because it came with a fiberglass roadster tank. The points are in the upper right side of the timing cover.

I don't find much information on locating this cam shaft correctly nor do I know how many options there are on positioning. Can you point me in the right direction?
 
Rondo said:
Maybe on 69's it in another location?
Click to expand...
69 Commando Timing ?
 
If I knew how to add a photo I would send you this one but there are no numbers in this location on this bike. Maybe the engine was changed out at some point but still curios there are no numbers at all?
If you could, not sure what is entailed in repositioning the breaker cam shaft correctly. Just as a side, seems like this breaker/cam was in the correct position when I first got this bike maybe I caused the cam to get out of sorts somehow? I have never removed the time advance unit though.
 
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Rondo said:
I don't find much information on locating this cam shaft correctly
Click to expand...

You need to remove the AAU from the camshaft taper...
AAU removal, Section C16, 3 & 4.
..Then refit it with the bolt and washer but only tighten sufficiently to hold it in place.

Rondo said:
nor do I know how many options there are on positioning.
Click to expand...

The position of the AAU in the end of the camshaft is 'infinitely adjustable' so with the points plates set to their mid positions, turn the AAU until the points cam is within the points plate adjustment range when the AAU cam is rotated to the fully advanced position, but without moving the camshaft and the crankshaft should be kept at the 28 degrees BTDC timing mark.

Once the AAU position has been adjusted then the AAU bolt can be tightened to 'set' the AAU into the camshaft taper. The points gaps and static timing can then be set (and preferably strobed after the engine has been started).
 
Thank you so much, I will work on that. We have messed with this timing so much I'm thinking we must have actually moved the shaft some when the bolt was loose or removed.
 
IS there a tutorial for attaching photos for future use? I've tried a few times but with no luck (my grandkids aren't here)
 
Rondo said:
IS there a tutorial for attaching photos for future use? I've tried a few times but with no luck (my grandkids aren't here)
Click to expand...

Only VIP members can upload directly.

Non-VIPs must upload to an image hosting website such as https://postimages.org/ or similar (but not photobucket) then 'copy' and 'paste' the image code (the 'Hotlink for forums' option for postimage) into their forum message.

Or a tutorial for imgur:
www.accessnorton.com

Picture Hosting Tutorial with Imgur

@Jerry Doe @L.A.B. feel free to move this post wherever you would like. Do not use Photobucket for photo hosting. I think we all learned our lesson there. Shoot, I got burned by Flickr too. I use Imgur, it's 100% and will never go away (as soon as I say that it'll get bought by Google and...
www.accessnorton.com www.accessnorton.com
 
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Thank you!! In the process of making an AAU removal tool, after researching it appears to be a 5/16-24 threaded bolt with one of my large sockets sliding on it to form a hammer effect?
 
Rondo said:
Thank you!! In the process of making an AAU removal tool, after researching it appears to be a 5/16-24 threaded bolt with one of my large sockets sliding on it to form a hammer effect?
Click to expand...
Yes, AKA a slide hammer. I have an old automotive dent puller that I've modified for that.
 
Interesting tool how do you use this one? Doesn't look like a slide hammer device.
I did get the shaft removed, readjusted, timed and started the bike for the first time. What a monster, sounded really good, drove up and down my street a couple times (low RPMs) now we will put a timing light to it. A few leaks but not too bad, worst is the kickstart shaft, so I'll need to find an O-ring. This accomplishment sure boosted the confidence level a bunch. Now we'll start working on the 73 and 75. Thanks again for all the helpful instructions.
 
After listening to advice, all good, I'd like to express my experiences. You can retard the timing slightly and it will kick over easier, but the exhaust pipes will also turn dark blue. I'll set my timing advanced where if you give it a lazy kick it will kick back. Give it a swift kick and it'll start every time. Not an expert just hate blue pipes.
 
Well, we tried to time the 69 with a light yesterday. For some reason it was running much rougher than last week after our successful static time and the only thing I did to change anything was to put the air cleaner on it? The firing is really intermittent and the timing mark was jumping all over for both cylinders. We then just tried going by sound but once again we could not get either cylinder to sound like it was firing in a consistent order. Not sure where to go from here, I hate to buy electronic ignition if that's not the problem but very willing if that would correct this. Any suggestions would be greatly appreciated.
 
You might try running the timing light off a separate battery. The mark shouldn't be jumping around. When I used to have points it was important to make sure the points gaps both remained at .015" after moving the points plate when setting timing. Sometimes there is some slop in the positioning of the points plate in the points cavity.
 
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