Norton N15CS Hybrid restoration

I really like the old Matchless twins, and I really like the old Norton twins. But when AMC was in trouble and they started to bolt parts from two different grand old marques together for whatever reason, it just always made me sad to look at them, a reminder of how mismanagement destroyed everything that was good about British bikes.... Looks like a horse running around with a cat's head sewed on.
 
grandpaul said:
This project has been eating my lunch. Everything shapes up nicely 'till I get it all back together then it just refuses to fire.

I'm on the third teardown ................ One thing for sure, it'll be done RIGHT.

Let he who is without sin cast the first stone...
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yes one things for sure...

hopefully the 4th time is the charm? :shock: ... :roll:
 
Yes, I believe it will be. I've garnered all the specific shop manual pages and am going through them sentence by sentence. SOMETHING has to be missing here.

There's no way the mag just gave up, it's a total overhaul with a new armature and was shooting a mighty blue spark before. Taking it off with the engine in place is a mother...

(no, a bit of cigarette paper didn't stay stuck in the points)
 
you can lead them to water but you can't make them drink. I gave up on this one a while back as some just have to pee on the electric fence before they learn.

ludwig said:
grandpaul said:
..I'm on the third teardown (twice to the primary, once all the way back down to re-check the rod bolts & big end shells; one of those times it got the thick base plate, this last time it's getting the cam drive timing checked)..... One thing for sure, it'll be done RIGHT..
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Just out of curiosity , I scrolled over this entire thread .
Initially I tried to advice you on possible pitfalls , but after I noticed that you didn't even bother to upgrade the layshaft bearing , I kind of gave up .



(quote) "Please , don't let me stop you , but trust me on this : GP , or somebody else will be doing this all over soon enough .
Like a wise man said :
"There is never time to do it right , but there is allways time to do it again !" (unquote)
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grandpaul said:
Yes, I believe it will be. I've garnered all the specific shop manual pages and am going through them sentence by sentence. SOMETHING has to be missing here.

There's no way the mag just gave up, it's a total overhaul with a new armature and was shooting a mighty blue spark before. Taking it off with the engine in place is a mother...

(no, a bit of cigarette paper didn't stay stuck in the points)
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The "new" style of points are not the best (at best) - they can cause the mag/points to ground out if not precisely setup and result in no sparky - (had it happen and drove me crazy trying to figure it out)

if your rebuilt K2F isn't throwing a spark but was before hand and your sure it is being spun by the engine I'd check that out - if you have a set of the original points with the brass plate they are the best ( magneto guys frequently buy old clapped out K2Fs just for these original points setups ) - try replacing them

and a match book is not the way to set the points - despite what old manual/shady tree shop tech update you may have :shock:
 
Mike, thanx for that info, finally something worthwhile.

I believe I have a set of the old type K2F points to swap out.

It's definitely turning with the engine, and not slipping on it's taper.
 
If you test the timing method of using a cigarette paper against a strobe light, its surprising accurate. Done well.

Just make sure you do it on both cylinders - maggie cam rings are often not so symmetrical...
 
Paul, Any updates on this project? I myself bought an N15CS project bike on a recent trip to California for $500, it's not as complete as it might be, but a good basis for a restoration and I intend to keep it there at a friend's house and do some work on it on my annual trips to California. I will post some photos the next time I visit in August.
 
mikegray660 said:
grandpaul said:
This project has been eating my lunch. Everything shapes up nicely 'till I get it all back together then it just refuses to fire.

I'm on the third teardown ................ One thing for sure, it'll be done RIGHT. quote]

yes one things for sure...

hopefully the 4th time is the charm? :shock: ... :roll:
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Something appears to be very wrong here.
I don’t know how good an engine restorer you are, but it seems to me you should obtain for the engine a degree disc and mount it on the crankshaft and find top dead centre, then find out where the inlet valve is opening, closing, same for the exhaust. (as per workshop manual)
Then observe the ignition timing with a wire, bulb and battery method, with the centre bold of the magneto removed for this purpose.#
Have you checked that your carb pilot jets are not blocked, and the screws are screwed out one and a half turns :?:
HTH.
 
I've gone through almost everything from top to bottom, and I'm in the process of what I HOPE is the last time I'll be buttoning up the timing cover after re-checking the timing pinion alignment (it was correct).

I need a new battery for my starter rollers, and I need to find where I put away the intake manifold mounting studs in order to re-install the properly sorted late-spec concentric carbs. After this, there is no reason on earth that it shouldn't start up once the engine gets rolling on the starter. Every spec has been checked and re-checked, and ALL systems are properly timed and adjusted.

I have to admit I've been distracted with too many other things to be able to drop everything else and just get this done; but life gets in the way and the bills don't stop coming even though the income stream slows down.

As if to pour salt in the wound, the bike fell off the stand and smashed the rebuilt speedo, so it has to go back to refurb once again. Thankfully the bodywork was not on the bike or it might've been worse.
 
grandpaul said:
I've gone through almost everything from top to bottom, and I'm in the process of what I HOPE is the last time I'll be buttoning up the timing cover after re-checking the timing pinion alignment (it was correct).

I need a new battery for my starter rollers, and I need to find where I put away the intake manifold mounting studs in order to re-install the properly sorted late-spec concentric carbs. After this, there is no reason on earth that it shouldn't start up once the engine gets rolling on the starter. Every spec has been checked and re-checked, and ALL systems are properly timed and adjusted.

.
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The ignition timing can be set on the wrong stroke, it should be set when checking the LH inlet valve has opened and closed and set x degrees before TDC. (With Magneto, if that’s what you have, set on full advance)
If all else frails try filling an oil can with gasoline and squirting some fuel into the carb bellmouths.
 
Timing was set on the correct stroke, and triple-checked for accuracy with a degree wheel on the crank (actually pulled the engine out of the frame for that entire fiasco).

Anyway, it's close, mighty close. I'm paying a generous premium for taking my time, but it will be right when it's delivered.

Regardless of the setbacks, it's one cool-looking bike, and it will run as good as it looks.
 
Here are shots of the timing check using the degree wheel. First, set the crank at TDC...

Norton N15CS Hybrid restoration


Then, verify and mark the plunger tool for future reference (sorry for the blur)...

Norton N15CS Hybrid restoration


Next, back the crank up about 20 degrees, then turn forward to 12 degrees Before Top Dead Center (BTDC)-

Norton N15CS Hybrid restoration


Re-verify and mark the plunger at the lower mark -

Norton N15CS Hybrid restoration


Then, re-checked the magneto; it was SPOT-ON. There just isn't anything else to check. Re-installing the carbs with the proper hardware, and using the roller starter, it WILL start.
 
If its not igition, then it must be fuel.
Remember that 99% of carby problems are electrical, and vice versa....

Pour a small teaspoon of fuel down the plugholes - if it then kickstarts easily, its carbie(s).
 
I must be missing something here, but, that degree wheel photo shows 10-2=8 not 10+2=12. I don't suppose that it would make a large difference on starting though.
 
motorson said:
I must be missing something here, but, that degree wheel photo shows 10-2=8 not 10+2=12. I don't suppose that it would make a large difference on starting though.
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It should make a difference. Don't know what the #$%^&* I was thinking, but it's that kind of stuff that's wearing me out. Thanx a ton for pointing that out, I needed to catch a break.
 
Coincidentally, (or conspiratorially), the settings are all exactly as they were with just the plunger; so perhaps that shows that the 4 degrees difference at the crank is not discernable with the plunger method?

Hmmmmmmm...
 
It is because 4 degrees is probably equivalent to only maybe 10-20 thousandths of piston travel. You can't see that little movement on that stick. This is what happens near TDC and BDC. That's why you really need the piston stop method to accurately determine TDC. (Find each side then determine the middle, which is TDC, from that.)

Also another problem: The spark plug hole and therefore the tool is not vertical to the piston so that will change the measured distance before TDC. Remember your high school trig.
 
I'm not atempting to measure piston travel with the plunger, just the relative position with an easy-to-see indicator.

I've times plenty of bikes using a rod or screwdriver down the cylinder, and always got them close enough tio fire so I could strobe time them. Of course this bike has no provision for strobe timing, so that's irrelevant; my point was that the plunger has it's place.
 
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