Norton N15CS Hybrid restoration

grandpaul said:
I'm not atempting to measure piston travel with the plunger, just the relative position with an easy-to-see indicator.
Click to expand...

which is... measuring piston travel. I thought we are talking about possible sources of error and since you've been thru this so many times and it is a customer's bike, you might try to make it as perfect as possible .

I have also timed plenty of bikes with a stick but it is always a vertical stick.
 
Yes, I'm going to re-time the mag with the degree wheel, and align it on TWELVE degrees BTDC this time.

Still waiting on replacement carb mounting hardware from Walridge, the mail system lost a set that was sent to me a month ago...
 
This actually raises the question of why you are timing to 12 degrees anyway ?
The timing figures for a P11 are 32 degrees BTDC, fully advanced.
Are the N15CS's that different, at all ?

Can't say I've ever seen a fully retarded timing figure published = dangerous practice, since wear etc can considerably affect how much retard a particular magneto or point set can give. And its the fully advanced timing you want to be spot on...

???
 
This is according to the N15 workshop manual...

Norton N15CS Hybrid restoration


NOW I remember why I set it there; thought I was REALLY losing it.

If anyone has a better idea, please speak on...
 
Isn't it saying though that 8 degrees is .022, so you'd need 4 times that ??
Rather ambiguous ?? (.022 is almost nothing).
That technique, and difficult starting, speak for themselves. ?

Whatever, although interesting, can you strobe time it at 32 degrees ?
Or static time it there...
 
I've never seen instructions for strobe timing a magneto equipped bike, although I suppose I could leave the primary cover off, set up a rigid pointer and mark the alternator rotor...

Of course, there ain't no strobe timing 'till it's running...
 
grandpaul said:
I've never seen instructions for strobe timing a magneto equipped bike, although I suppose I could leave the primary cover off, set up a rigid pointer and mark the alternator rotor...
Click to expand...

Yes. strobe timing would be good, if you can bear to remove the primary cover and mark the stator. That is how I time my own mag ignition and it shows that the ciggy paper method is not always that accurate. I'd scrap that pointer in the plug hole and use a piston lock stop to determine TDC. Then you will know for sure that it is at 8 deg fully retarded. Please excuse me for asking this, but are you certain that the points are opening before TDC compression and not TDC overlap? I only mention it because all of us have got caught out occasionally with things like this.
 
daveh said:
Please excuse me for asking this, but are you certain that the points are opening before TDC compression and not TDC overlap? I only mention it because all of us have got caught out occasionally with things like this.
Click to expand...

Yes, triple-checked.

Again, strobe timing won't be possible till the engine is running unless it'll trigger the strobe accurately spinning it on the starter rollers...
 
grandpaul said:
I've never seen instructions for strobe timing a magneto equipped bike, although I suppose I could leave the primary cover off, set up a rigid pointer and mark the alternator rotor...

Of course, there ain't no strobe timing 'till it's running...
Click to expand...

You don’t need a strobe for timing a magneto equipped bike, back in the day all we had was a bit of wire from a wire coat hanger and a timing disc - never had any problem with this method, if applied correctly.
BTY when setting ignition timing, when looking directly at the timing disc, which way do you set the engine before TDC, clockwise or anticlockwise :?:
 
"BTY when setting ignition timing, when looking directly at the timing disc, which way do you set the engine before TDC, clockwise or anticlockwise "

Its before top dead centre.

So turn the engine in the normal running direction and stop the correct number of degrees before top dead centre. If the degree wheel is mounted on the crankshaft on the left hand drive side of the bike then it will be rotating in an anticlockwize direction.

I think it is a good idea to use a strobe on any sort of ignition and my mag works fine with a strobe. Check both cylinders.
 
grandpaul said:
Very good suggestions; this one has a cush hub clutch???

I have a couple of Atlas heads, I intend to refurbish the best of the batch and use it.
Click to expand...

Not gone though the whole post again, but……….the Atlas cylinder head is NOT interchangeable with a Commando head one is for spigot barrels the other not.
 
The head on the bike is the exact part for this year/model, as per the parts book and Atlatic Green website tech section on Norton heads.
 
No progress since installing carbs.

Adoption in progress necessitated out-of-town specialist doc visit, just back.
 
Paul, I noted on going back through this thread that you started it on April Fools day 2009, was that deliberate or a freudian slip?
 
Finally running and being detailed.

The seal blew on the bike stand, causing a crushed tach that just got back from overhaul after never having turned a rev from it's first overhaul.

Correct front brake cable and replacement tach drive for one that went astray are on thier way.

Client is very gracious, especially since I picked it up and stored it for well over a year before he actually gave me the go-ahead on the project. I'm giving him free return shipping plus cancelling part of the balance owed due to the various delays.
 
Presumably the crushed tach s not related to the problems with starting the bike. I am curious as to whether you identified and solved the starting issue as I am now a G15 owner myself. It is a truism that the last 5% of the restoration takes 90% of the effort.
 
Magneto overhaul by subcontractor was not adequate. 'Nuff said on that painful topic.
 
Been there, done that, now am rebuilding Lucas (only) mags in my shop. Let me know if I can be of any help
 
You must log in or register to reply here.
Back
Top