P11 basket case

So I'm slowly accumulating parts and ideas:

--I picked up an oil tank from A Popular Auction Site, it's a steel one from a Ranger, I think, but it will do until something better comes along.

--also a magneto friendly timing chest cover, one without a hole for the tach drive and with a neat little brass patent number tag mounted in the middle of it. I guess it came off of a Dominator.

--I made an offer on a set of Ceriani triple clamps, I have an idea what fork legs and front wheel I am going to use, but I hesitate to reveal that just yet.

--I'm working on a deal for an Atlas engine to use as a parts donor

--it sounds like I have a AMC pattern gearbox housing, but so far nothing in it. I've been offered Commando parts to stuff it with, how does a P11 gearbox compare to a Commando gearbox? Closer ratios? Wider?

--I'm not certain what to do about a clutch; I've been offered a 3 spring clutch, ("as used on Manx Nortons"), will it be strong enough? I really like the sound of an NEB, but they are a bit dear.

--speaking of NEB, I also like the look of their belt drive. Hypothetically speaking, if I could sell a kidney and buy bike parts, would an NEB belt drive be worth having? I've always been impressed with how well the final drive belts hold up on Harleys, surely a belt primary drive on a Norton could only be a good idea?

--I need a seat. Who sells the best P11 (short) seat?

--I need exhausts pipes, who sells the best P11 high pipes?

--definitely going with a magneto, I have access to a K2F, should I get it rebuilt? I really like the Joe Hunt mags, but they are pricey!

--I see that P11's seem to have come with dual carburettors from the factory, but a lot of restored ones are running singles. I understand (very well) the appeal of a single carb from a maintenance point of view; how much is performance affected?

Thanks for your help, everybody!
 
So I'm slowly accumulating parts and ideas:

--I picked up an oil tank from A Popular Auction Site, it's a steel one from a Ranger, I think, but it will do until something better comes along.

--I made an offer on a set of Ceriani triple clamps, I have an idea what fork legs and front wheel I am going to use, but I hesitate to reveal that just yet.

--it sounds like I have a AMC pattern gearbox housing, but so far nothing in it. I've been offered Commando parts to stuff it with, how does a P11 gearbox compare to a Commando gearbox? Closer ratios? Wider?

--I'm not certain what to do about a clutch; I've been offered a 3 spring clutch, ("as used on Manx Nortons"), will it be strong enough? I really like the sound of an NEB, but they are a bit dear.

What's wrong with the steel oil tank? It's rubber mounted, probably the best designed oil tank AMC and NV ever made ....

A Ceriani triple tree will not fit the P11 frame unless some serious and irreversible modifications are made to the headstock. Same goes with Roadholder forks. You are initially stuck to using AMC parts, but what's wrong about them? Think twice.

AMC pattern gearbox housing? Never heard of any. There was a Quiafe reinforced shell available for Nortons and AMC race bikes at some point in time; it will not fit the P11. Again, you should use an AMC/Matchless version gearbox shell, preferably one off the post-62 gearboxes type stamped "MA" which had numerous improvements.

As for clutch, again it's imperative that you use the post-60 type of clutch which was an improvement over the previous version. Still, it will struggle to handle the torque of the Atlas/G15 engine unless meticulously set up. See another thread on this subject. The NEB clutch is not recommended as a torsion damper is missing which the AMC clutch has built-in. Without it you may expect transmission to have a short life unless a cushioned final drive is fitted. This however doesn't go well with the off-road capability of the bike. AMC's cushioned rear hub is unsuitable for use on the P11.

-Knut
 
--definitely going with a magneto, I have access to a K2F, should I get it rebuilt? I really like the Joe Hunt mags, but they are pricey!

Definitely yes to a rebuild. You are dealing with near 60 year old internal wiring, and capacitor. A thorough rebuild will set you back about $500.

You can apply that money to a JH providing you like the look of them hanging off the timing cover.

Slick
 
What's wrong with the steel oil tank? It's rubber mounted, probably the best designed oil tank AMC and NV ever made ....

A Ceriani triple tree will not fit the P11 frame unless some serious and irreversible modifications are made to the headstock. Same goes with Roadholder forks. You are initially stuck to using AMC parts, but what's wrong about them? Think twice.

AMC pattern gearbox housing? Never heard of any. There was a Quiafe reinforced shell available for Nortons and AMC race bikes at some point in time; it will not fit the P11. Again, you should use an AMC/Matchless version gearbox shell, preferably one off the post-62 gearboxes type stamped "MA" which had numerous improvements.

As for clutch, again it's imperative that you use the post-60 type of clutch which was an improvement over the previous version. Still, it will struggle to handle the torque of the Atlas/G15 engine unless meticulously set up. See another thread on this subject. The NEB clutch is not recommended as a torsion damper is missing which the AMC clutch has built-in. Without it you may expect transmission to have a short life unless a cushioned final drive is fitted. This however doesn't go well with the off-road capability of the bike. AMC's cushioned rear hub is unsuitable for use on the P11.

-Knut


--Maybe nothing is wrong with the steel tank. For now I'll use it. Alloy is just sexier, I guess.

--Ceriani triple clamps won't fit? Seriously? There's not even a stem in the clamps yet, so I'm counting on having to machine one to fit both the clamps and the headstock. Is this really impossible? Seems unlikely.

--"AMC pattern gearbox housing" I see that I have miscommunicated. What I mean is: "I have an AMC/MAtchless gearbox shell". Thanks for the correction.

--Knut, thanks for the info on the clutch, that's valuable to me and is the reason why I come to places like this.

It's a little frustrating being on one side of the planet, with the bike on the other side of the planet, and having to rely on info I get from forums and friends as to what will fit, but I'm doing it. And I will succeed in the end.
 
Definitely yes to a rebuild. You are dealing with near 60 year old internal wiring, and capacitor. A thorough rebuild will set you back about $500.

You can apply that money to a JH providing you like the look of them hanging off the timing cover.

Slick

I've found a guy in Washington, (related to one of my wo-workers, actually), who specialises in rebuilding Lucas mags, especially K2F's, apparently. He says he can do it for $400. I guess the reason why I am balking just a bit is because I am not sure what kind of shape my AAU is in and so I'm tempted to spend a bit more and just get a mag that has it's own advance mechanism built into it. The Joe Hunt mag will fit behind the cylinders, just like the K2F. And has the advantage of being easier to service in that space than the K2F is. Or so I'm told.
 
I've found a guy in Washington, (related to one of my wo-workers, actually), who specialises in rebuilding Lucas mags, especially K2F's, apparently. He says he can do it for $400. I guess the reason why I am balking just a bit is because I am not sure what kind of shape my AAU is in and so I'm tempted to spend a bit more and just get a mag that has it's own advance mechanism built into it. The Joe Hunt mag will fit behind the cylinders, just like the K2F. And has the advantage of being easier to service in that space than the K2F is. Or so I'm told.

If your K2F needs a cam ring, add $100 ..... My estimate was on the high side.

There was a thread on this Forum that discussed Joe Hunts mounted behind barrels..... The consensus of opinion, as well as experience, was that the heat from the barrels tended to kill the super magnets over time. Use the search function to get more info.

Perhaps JH has found next generation, heat tolerant super magnets at this time. I would give them a call and get the latest on this issue.

I am not aware that JH has any advance mechanism. Perhaps they do at present ..... another point to discuss with someone from JH.
In any event, the Lucas AAU can be mounted on the JH shaft when the magneto is behind the cylinders.

Slick
 
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If your K2F needs a cam ring, add $100 ..... My estimate was on the high side.

There was a thread on this Forum that discussed Joe Hunts mounted behind barrels..... The consensus of opinion, as well as experience, was that the heat from the barrels tended to kill the super magnets over time. Use the search function to get more info.

Perhaps JH has found next generation, heat tolerant super magnets at this time. I would give them a call and get the latest on this issue.

I am not aware that JH has any advance mechanism. Perhaps they do at present ..... another point to discuss with someone from JH.
In any event, the Lucas AAU can be mounted on the JH shaft when the magneto is behind the cylinders.

Slick

Slick, are you in any way connected to Slick Magnetos?
 
Slick, are you in any way connected to Slick Magnetos?

No ..... I earned the sobriquet "slick" because of a slick wind tunnel probe I invented as a graduate student. Now a days, I live up to it because of my pate. Occasionally, I come up with another slick idea.

slick Slick
 
The Joe Hunt mag will fit behind the cylinders, just like the K2F. And has the advantage of being easier to service in that space than the K2F is. Or so I'm told.

What kind of service do you want to perform in situ, apart from adjusting the points? Being brand new and lighter than the K2F, the JH magneto looks like a good proposition, but it is bulky and being made out of alloy it will pick up more heat than a Lucas K2F. As has been mentioned above, sealing against petrol drip may be a concern. Cost-wise the two options are probably rather equal. You need an AAU for both which will cost another §100 for a good used sample.

-Knut
 
What kind of service do you want to perform in situ, apart from adjusting the points? Being brand new and lighter than the K2F, the JH magneto looks like a good proposition, but it is bulky and being made out of alloy it will pick up more heat than a Lucas K2F. As has been mentioned above, sealing against petrol drip may be a concern. Cost-wise the two options are probably rather equal. You need an AAU for both which will cost another §100 for a good used sample.

-Knut

Hang on a sec--are you saying that a K2F housing is made out of something other than an aluminum alloy?
 
Hang on a sec--are you saying that a K2F housing is made out of something other than an aluminum alloy?

The Lucas K2F is a "bass - ackwards" magneto. Most magnetos employ a rotating magnet surrounded by a stationary wire coil. The K2F has a rotating wire coil (armature) surrounded by a stationary magnet. The housing is that magnet and is iron.

Slick
 
Yeah, I noticed from pictures that it looked odd, what with the points in the middle and the points cam running around the outside. Magnetos like these are all a little new to me, every other bike I've ever owned has had a points plate bolted somewhere on the engine (or a pulser coil/pickup coil/[insert favorite term here]) with power going to it either from a battery or from a dedicated source coil in the usually permanent magnet style alternator.

Anyway, I'm excited to expand my knowledge and experience, which is part of the reason I am here.
 
Yeah, I noticed from pictures that it looked odd, what with the points in the middle and the points cam running around the outside. Magnetos like these are all a little new to me, every other bike I've ever owned has had a points plate bolted somewhere on the engine (or a pulser coil/pickup coil/[insert favorite term here]) with power going to it either from a battery or from a dedicated source coil in the usually permanent magnet style alternator.

Anyway, I'm excited to expand my knowledge and experience, which is part of the reason I am here.
Suggest you look up the troubles of the K2F mags and the solution to rectifying their faults they are on this and other websites . . . .
 
Suggest you look up the troubles of the K2F mags and the solution to rectifying their faults they are on this and other websites . . . .

Thanks--I've already started to pick up some of that info, which is one of the reasons why I was (am) considering a Joe Hunt mag. I'm also finding that magnetos seem to be one of those things that fall very much into the "Your Results May Vary" category. It doesn't seem to matter what brand of magneto we are talking about, you'll find fans and haters of each one. Ditto with electronic ignition systems.
 
Suggest you look up the troubles of the K2F mags and the solution to rectifying their faults they are on this and other websites . . . .

There are no particular problems associated with the K2F mag that I am aware of. I wouldn't rate loss of magnetism after almost 60 years or a worn armature thread as design issues! As for the oil mist and pressure problem, that is a consequential effect of other faults and shortages - magneto design is not to be blamed.
Overall, a serviced K2F is a reliable and durable instrument. Some do their duty even after 40 years ....

-Knut
 
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There are no particular problems associated with the K2F mag that I am aware of. I wouldn't rate los of magnetism after almost 60 years or a worn armature thread as design issues! As for the oil mist and pressure problem, that is a consequential effect of other faults and shortages - magneto design is not to be blamed.
Overall, a serviced K2F is a reliable and durable instrument. Some do their duty even after 40 years ....

-Knut

Agree!

The original capacitors die of old age .... usually at 40 - 50 years. Mine lasted 53 years. Modern replacement capacitors have the potential to last twice as long.

My K2FC has been professionally rebuilt, and I expect to hand the Atlas off to my son, and I feel confident he will have no issues with it in the remainder of his lifetime.

When properly set up it is the most reliable, trouble free ignition one can have on a 50 to 60 year old vintage bike. One can argue that the Joe Hunt is better, but it is not fair to compare modern technology with vintage.

The major problem Bernhard may be alluding to is that of timing mis-match. This is not a design fault per se, but rather of tinkerers who fiddle with these instruments without a clue. See https://www.accessnorton.com/NortonCommando/setting-up-and-timing-a-k2f-magneto.19685/ for the proper way to eliminate timing mis-match.

Slick
 
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Okay, well, now that we've discussed magnetos...

I need a short seat. I see a number of places on the interweb where they are sold, are they pretty much all the same? Who sells the best replica P11 seat?
 
Finally found pics of my P11 but can't figure out how to post them just yet.
 
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Ah, here we go:

P11 basket case


P11 basket case
 
Not pictured is the fuel tank, which has been modified to fit some other frame, but could possibly be restored to fit a P11 frame. Or I may just look for another one.
 
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