Dissasembling first Norton (N15CS), 16 y/o son is intrigued....

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After restoring 3 big UJMs ('79 GS1000E, '82 Mr Turbo GS1100E, '73 Honda CB750K) I have turned my attention to the '66 N15CS. My son has been watching Allen Millyard and enjoys watching him, as do I. I know there are non-fans of his but I don't care, he has gotten my boy to get in the garage with me and really work. Oh I also promised him he can have the Norton as his own if he listens to his subordinate engineer (me). Last night we worked 4 hours and forgot about dinner.

The bike, oddly enough (heh), seems to have been misted quite thoroughly with oil, so no dramas with rusted fasteners. I think this design feature is best perfected by the British. I have pullers and pry bars and a torch etc, so I got the stubborn bits off, the sprocket followed by the cam chain bolt, then the stator and clutch pressure plate in descending order of difficulty not removal. Engine on furniture dolly and son sitting on it to steady as I use a couple 3 foot pry bars... magic times. One thing left, pinion gear, nut is off but how to pull I'm not sure yet, I'm sure a special tool or home brew way.

As I disassembled I think I found out the reason for the spare set of '70 Commando cases that came in the pile - a split in the case at a barrel stud. It's not the serial #'s side which is good (plus the other side of my Commando case is cracked quite well and not usable). A one minute look tells me to see if it's possible and a good option to use the Commando. Someone will school me here possibly. The intermediate sprocket shaft is shorter and the magneto mount is different. At this point I have no idea what a Commando ran in '70 for ignition so I'll check things out and also if a repair and upgrade is a better choice. Opinions welcome, sorta - go easy on me!

Not a mechanic but have opened quite a few engines (and made them run again even!) overall I'm very happy with its condition. It's not buggered and all the correct hardware is there, with possible exception of 3 hex bolts on the clutch housing which mated up suspiciously well to my SAE 3/16 wrench. We have lots to learn but in the end plan a 'runner' with some stuff grafted on as I see fit like a front end from one of my 70's Suzuki GSs spares. I simply can't afford Norton stuff's prices right now.

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Oh I got the pinion off in 5 minutes after looking at a post about a hack using tire irons HERE:

I gave it a minute or so of low heat with the torch after a shot of penetrating oil and then put an ice cube on the center shaft. It came off without many torques, so nothing harmed. Here is a pic recreating the glory in case it's not clear or it helps some other butcher.

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First suggestion take plenty of photos!, as you can see in your photos the revcounter drive on the Commando Case is in a different position i.e. it drives off a worm drive on the camshaft as apposed to the N15 where the drive attaches to the timing cover and drives off the end of the cam therefor there is no worm drive on the N15 Cam, again the Commando points setup drives off the end of the cam where as the N15 probably has a magneto mounted off the rear of the right side crankcase [the Commando appendages in the right side case were for a proposed starter motor that never happened], Also the idler sprocket that carries the second chain to drive the magneto [or points] on the N15 had a shim behind [unsure if the shaft was longer] where as the 20M3S type Commando did not have a shim. I would suggest see if the N15 case is weldable I have seen cases with holes in repaired.
 
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First suggestion take plenty of photos!, as you can see in your photos the revcounter drive on the Commando Case is in a different position i.e. it drives off a worm drive on the camshaft as apposed to the N15 where the drive attaches to the timing cover and drives off the end of the cam therefor there is no worm drive on the N15 Cam, again the Commando points setup drives off the end of the cam where as the N15 probably has a magneto mounted off the rear of the right side crankcase [the Commando appendages in the right side case were for a proposed starter motor that never happened], Also the idler sprocket that carries the second chain to drive the magneto [or points] on the N15 had a shim behind [unsure if the shaft was longer] where as the 20M3S type Commando did not have a shim. I would suggest see if the N15 case is weldable I have seen cases with holes in repaired.
Yes thanks great info, I am always documenting and labeling, having so many bikes I have to!

I'm working sort of quickly and will split cases tonight. Yeah the magneto is up at the rear right, three bolts in a triangle.

My friend who has a '55 Corvette has rented a paint booth and I've been helping, and in two weeks I can have access to the booth after we finish his 2nd primer coat. I have 98% of the parts for the bike already so I can paint them with some nice black 2 stage urethane I've been saving. All I'm missing is the side stand and whatever the guts of the tool case are. So we can do a few things, degrease the motor and throw in the ultrasonic (and I can teach him how to polish aluminum on the buffer), and get the frame and mudguard etc done.

I will assess the crack better when it's apart but I am hopeful it can be mended as that conversion sounds much more involved. I can't see any split inside so far but can't see it all yet.
 

N0rt0nelectr@

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Looks like the crack goes into the camshaft tunnel? You will need to remove the camshaft bushing to make sure.
 
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Looks like the crack goes into the camshaft tunnel? You will need to remove the camshaft bushing to make sure.

Due to cost of repair I looked and found a good replacement for a decent price and it's on the way, I had the seller check for thread galling, any cracks. Hopefully all good. I will sell my '70 Commando case half and hopefully come out even, or close. The other side of that pair has a rod impact crack unfortunately. I'm glad that the issue is on the non serial number side!
 

mdt-son

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Crack at the t/s seems to progress into the wall which mates with the timing case. I wouldn't attempt normal welding, laser welding is a possibility. Lots of machining will be required.
Using another t/s case halve comes with its own challenges. The mating flange may not fit the drive side case halve due to warpage and possibly altered machining at the works. Good luck, and keep us updated.

-Knut
 

mdt-son

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I was touched by your story of involving your son into the world of mechanics. The companionship evolving around this hobby is far more valuable than enjoying man-made products like bikes.
I am equally blessed having a son with whom I share the interest of keeping older cars on the road as well as carpentry. So grateful for the time we spend together!

-Knut
 
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I was touched by your story of involving your son into the world of mechanics. The companionship evolving around this hobby is far more valuable than enjoying man-made products like bikes.
I am equally blessed having a son with whom I share the interest of keeping older cars on the road as well as carpentry. So grateful for the time we spend together!

-Knut
Thanks for kind words. If I can keep him from doing dangerous and stupid stuff like I did I'll have done my duty.

I've mated up the halves and it looks good, but time will tell. I have to finish a couple other bike projects that are pretty quick fixes before really diving in.
 
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Trying to do one thing, even if it's small, each day. I removed the dowels because both sides had them and I was able to punch out the ones with access from the back. Removed the cylinder barrel studs easily and took a look at all the threads, which look fine. I think this is a winner, ready to push onward. Pleased to make an eBay purchase that was exactly as described and even pretty clean. I met a guy at a local show who has a P11 and says he has some parts that I could use, fork legs and rear rim especially, will see.

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........ If I can keep him from doing dangerous and stupid stuff like I did I'll have done my duty......
This has been one of my main concerns raising my kids....so far only one of our middle daughters & our youngest son seem interested in working on things/ using tools (bicycles, scooters, etc...), that daughter sews, and that son likes wood working too. However they all seem to be dodging the dangerous and stupid stuff I managed to live thru. Keep the posts coming , I'm looking forward to following your rebuild thread. Mine has stalled... 6 kids equals no money at the moment.
 
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My apologies if this is really basic stuff but I took apart the crank and am happy with what I have found. It looks like it's never been apart which is always nice. I recently had to fix a few buggered threads on my Suzuki GS1000 with inserts, somebody got pretty aggressive with it. My Honda CB750 had never been opened and it was a treat to work on. This Norton is following suit in that regard.

There wasn't much sludge in the trap, maybe 1/8" of buildup at 180 degree spacing. I don't know how much I should expect but one video on an Atlas rebuild showed a huge amount of muck in there. One pair of rod shells has a groove down the middle, so something got in there. But the journals look OK. I'll have to get a some proper tools to start measuring. All the bearings appear to be very good too, no marks on them and they spin freely. I have heard of 'superblend' since the 70's, am reading up on them to understand if I need them or not, if they are applicable for this N15CS etc.

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Maybe I need to start a build thread.... I met a guy at the local Cars & Coffee who has some beautiful bikes, P11, Rickman Triumph and Montesa. He sold me a front wheel, forks, calipers, M/C disc brake setup off a 72 commando, and a rear wheel/hub assembly. Both better chrome than what I have, and disc upgrade will be nice to have. He has a nice TLS and the lowers are exactly the same, but although it looks beautiful it's out of my price range and I'm going for stopping power. Also picked up a nice set of bars.
 
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One pair of rod shells has a groove down the middle, so something got in there. But the journals look OK.
The groove is inline with the feedhole in the crank journal, so the oil pump has been supplying dirty oil to the shell bearings, the trimetallic ones have a soft lead indium overlay plating which absorbs the crud and keeps it off the journals but eventually the plating fills and then the journals get worn. So fit an oil filter in the return line to keep the oil clean, hopefully with the sludge trap being so clear the shells are toast but have protected the journals so they are still within size.
 
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The groove is inline with the feedhole in the crank journal, so the oil pump has been supplying dirty oil to the shell bearings, the trimetallic ones have a soft lead indium overlay plating which absorbs the crud and keeps it off the journals but eventually the plating fills and then the journals get worn. So fit an oil filter in the return line to keep the oil clean, hopefully with the sludge trap being so clear the shells are toast but have protected the journals so they are still within size.
The first thing I did when I inherited a '66 Triumph T120R was to fit an oil filter. That plus the better detergents in the oil is a big benefit. I'm in cleaning and learning mode still.

Since the rear Commando wheel I got is 19", I will see if I can sell it and get an 18 to stay with what the N15 had. I have taken apart the rear N15 hub except for the bearings. They're not budging. I have another bare hub that looks identical so I don't need to sweat it. I'm looking at the various parts to see what I can cobble together economically but correctly. I am hopeful that the Commando front forks (which I think are '73 not '72) will work with my yokes and also be reasonably close to the same length. If it doesn't work out I can deal with it, just hoping I can get the bike on its feet.

I have some nice black enamel to spray the frame and parts, so I'm prepping those. It's nice to have all my other bikes done and finally focus on the Norton.
 
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Before you pull the 18" N15 back wheel apart measure for rim positioning for re-spoking as I have searched for this information without success, Commando rear wheels are all offset to one side, and the part numbers for the wheel spacers are not recognised by Andover or RGM's website. the fork stauntions in the N15 are long roadholders and are slightly longer than commando, the bottom bush also attaches differently, check the fork dampening mechanism as the N15 that I am helping with is a cross between a Norton and a teledraulic {matchless] easy way to tell is the Norton/ Matchless setup had external fork springs the later internal. If your intention is to have an N15 that is close to original I would stay with the standard brake setup, even though the Commando disc brake sliders look similar they are oval not round like a drum brake set up, but "beauty is in the eyes of the beholder".
 
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Before you pull the 18" N15 back wheel apart measure for rim positioning for re-spoking as I have searched for this information without success, Commando rear wheels are all offset to one side, and the part numbers for the wheel spacers are not recognised by Andover or RGM's website. the fork stauntions in the N15 are long roadholders and are slightly longer than commando, the bottom bush also attaches differently, check the fork dampening mechanism as the N15 that I am helping with is a cross between a Norton and a teledraulic {matchless] easy way to tell is the Norton/ Matchless setup had external fork springs the later internal. If your intention is to have an N15 that is close to original I would stay with the standard brake setup, even though the Commando disc brake sliders look similar they are oval not round like a drum brake set up, but "beauty is in the eyes of the beholder".
I'm a knucklehead and saw this too late, I took apart without measuring. Now we're both up the creek I suppose. Sheesh, this makes me angry at myself as usually I am not one to dive into stuff without thinking things over. And I had seen your post too. Sorry about that in many ways.
 
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Ok, I had the same problem with my friends bike where he sent his wheels to a supposed expert to be disassembled re-chromed and reassembled, when i fitted the back wheel it was obviously to the right of centre, after some straight edge measurements it appeared to be 2.5mm to the right of centre which was corrected [and charged for] courtesy of a member of this forum the measurements of the wheel spacers are-
Washer 030023 measures 9/16 x 1 x 1/8"
Spacer 030018 measures 9/16 x 1 x 1-1/8"
Spacer 030017 measures 13/16 x 1-1/4 x 11/16"
 
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Couple of satisfying disassembly tasks today, got my Commando disc brake/forks and they were pretty seized and the stanchions are toast, but with the vice I was able to slam the forks apart. One was pretty tough, it had no cap and all the oil leaked out, the other was easier. The bushings and inners look pretty good so they are usable - well new bushings are likely. The brake caliper cover with the two pin holes was a challenge but I found two drill bits that fit really snugly when tapped in, and used a big pipe wrench on them and the fork secured in my vice to take it off with no damage.

I have a friend with a blast cabinet so I'll take the aluminum / ium bits and the stuff that will be painted black down on Monday and have at it. I have some good Nason black urethane and reducer/hardener I got free that I'll use, it lays on well and is tough stuff.
 
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Caliper not too shabby. Was sitting a long time and very grungy but compressor and some warmth freed it all up.

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