The p11a rear wheel

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I have to go into the wheel and replace bearings and I hope that's all. Where can I get a diagram of the hub?
 
This might help.

The p11a rear wheel


Hope you have the hub assembled in original condition with the speedo properly shimmed before taking it apart. If not shimmed correctly winding the speedo cable up on the rear axle can be exciting. Ask me how I know. Well, don't but you get the idea.

The OEM hub bearings are unique if it is the same hub I have on a '67 P11 not A. I got them from AMC Classic Spares. There may be other sources.
 
That is the most involved rear wheel innards I've ever seen. Is there a place that sells all these bits? Currently the rear wheel is missing the brake plate and parts. I can take the rear wheel and wiggle it where the bearings should be. The wiggle travel is a lot...as though the bearing holes are worn out or the bearings have collapsed. Thanks for the picture
 
The rear hub bearings are tapered roller and unique. With my rear hub getting the bearings out and reinstalling new bearings was fun in a I need a bigger hammer sort of way. Your bearings may come out easier. It should wiggle less with the brake plate and other parts you are missing. I can't guarantee it though. Mine does wiggle about 1/32". I can't say anything positive about the rear hub other than the spokes are straight pull and really easy to work with when lacing up a new rim, which by the way is also unique to the P11.

AMC Classic Spares has some parts for the P11 because the P11 shares pieces with Matchless scramblers, but the parts are not inexpensive, and you have to search through their database to see what they have. Very primitive website and it's not secure since they don't support credit card purchases. http://www.amcclassicspares.com/

There might be some P11/Matchless parts in the USA. You'll have to get your search on.
 
I am guessing that the tapered rollers are not adjusted and the wheel is flopping. My concern is when dealing with this wheel it could become a long project. That means the bike is immobile and takes up the floor space or the lift table until it's done which will be an open ended project. I would really like to substitute another Norton wheel.
 
I am guessing that the tapered rollers are not adjusted and the wheel is flopping. My concern is when dealing with this wheel it could become a long project. That means the bike is immobile and takes up the floor space or the lift table until it's done which will be an open ended project. I would really like to substitute another Norton wheel.

Yes, it is very possible the bearings are not adjusted. Should mention the bearings being sold today by AMC Classic Spares are referred to as improved and I think AMC Classic Spares has them made by I don't know who. I know that's not helpful. It just is.

There's no spec for torque on the rear hub axle nut in the Red Scrambles manual that covers G85CS, G80CS, and P11. Roll your own torque settings. There are two torque specs mentioned. Cylinder-head nuts 25 lb. ft., and Con-rod nuts 25 lb. ft. The P11 is an adventure without having to even ride it. :)

Replacing the hub and rim is a good idea for ease of maintenance.
 
I have to go into the wheel and replace bearings and I hope that's all. Where can I get a diagram of the hub?

This might help.

The p11a rear wheel


Hope you have the hub assembled in original condition with the speedo properly shimmed before taking it apart. If not shimmed correctly winding the speedo cable up on the rear axle can be exciting. Ask me how I know. Well, don't but you get the idea.

The OEM hub bearings are unique if it is the same hub I have on a '67 P11 not A. I got them from AMC Classic Spares. There may be other sources.
That looks way more complicated than necessary..
 
That looks way more complicated than necessary..
Norton Matchless Division design?

Probably could be improved upon by a competent machinist.

All that stuff on the skinny rod goes on that axle shown above it.

Below is a view I found of the bearings in the hub with axle inserted.

The p11a rear wheel
 
I am guessing that the tapered rollers are not adjusted and the wheel is flopping. <...> I would really like to substitute another Norton wheel.
Don't think about it. The P11/G80CS rear wheel is superior, because of very strong taper roller bearings, which should last a life long, a one-piece axle of sufficient diameter, and the straight-pull spokes.
BMW used a similar design on their airheads up to 1980 approx., front and rear.
Those taper roller bearings are very expensive now (about 70 GBP each).
Yes, the number of parts needed in the assembly looks unnecessarily complicated, but when you realize the bearings need to be protected against grit, and there is a need to apply compressive load at the inner races, the design necessarily becomes a little tricky. Other than that, there are numerous spacers. Not a big deal. Maybe AMC could have simplified the spacer arrangement. That's my only comment on the design.

A ball bearing conversion is a possibility, similar to what's offered for the pre-64 front wheel. Except for the felt dust protections, which can be dispensed with when using sealed bearings, a pair of ball bearings will need positive axial compression and retaining rings for the outer race. That's not much different to the existing design, the only difference being that no adjustments are needed.
A wheel hub having this design is less suited to being used as a scrambles bike, because radial bearings can't take high axial loads. Nevertheless, some dirt bike manufacturers provide rear hubs with ball bearings. They wear out rapidly. I guess it's a cheap solution for short-lived bikes.

- Knut
 
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P11's that were raced off road got some grit past the seals and in the rear hub bearings. If the bike was primarily used on the road in fair weather like a clean garaged P11A may have been, the bearings are probably in the OK range for a 56 year old bike. You have to get them out of the hub to find out.

All things considered the bike will roll with rear hub bearings that are not perfect, as shown below.

This is what a '67 P11 rear hub bearing race looks like after 5+ decades. It was still rolling before I replaced them. Difficult to lube well from the outside of the bearing. Easier from the inside of the bearing, but they have to be pounded out of the hub to get at the inside.

The p11a rear wheel


View of what would be accessible with the bearing still in the hub with spacers and seal removed.
The p11a rear wheel


I'm guessing the P11A project is parked in a corner of your garage by now. ;)
 
P11's that were raced off road got some grit past the seals and in the rear hub bearings. If the bike was primarily used on the road in fair weather like a clean garaged P11A may have been, the bearings are probably in the OK range for a 56 year old bike. You have to get them out of the hub to find out.
From the 1963 AJS service manual:

1707582250042.png


The lubrication interval for a road bike is every 1500 miles for these hubs. There are no maintenance interval for off-road bikes (G85CS/G80CS/P11), which means they will need service as required. By washing the felt seals in petrol and impregnating them with grease/oil, as well as keeping the hub incl. felt seals packed with grease, grit should be effectively kept away from bearings. Of course, if owners neglect basic maintenance, even the simplest design fails in the end.

- Knut
 
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There is no felt seal in a P11 rear hub. They are rubber seals.

Here's a pic of my Norton Villiers Norton Matchless Division G85CS-G80CS-P11 Maintenance Manual cover.
The p11a rear wheel


Below is what the book says about the hubs on page 13. The rear hub does have a 10,000 mile maintenance interval apparently.
The p11a rear wheel


The rear hub bearings never failed on my P11, but as rugged and long wearing as they are I decided they were overdue for replacement after 57 years. The rear bearings are not that easy to grease, but it can be done. I probably did miss a grease interval or two. lol
 
Norton Matchless Division design?

Probably could be improved upon by a competent machinist.

All that stuff on the skinny rod goes on that axle shown above it.

Below is a view I found of the bearings in the hub with axle inserted.

The p11a rear wheel
 
So how do you adjust the inner race to just the right amount of pressure?...just touching but no pressure and no slop? And when the axle is tightened it will reduce the nil clearance.
 
So how do you adjust the inner race to just the right amount of pressure?...just touching but no pressure and no slop? And when the axle is tightened it will reduce the nil clearance.

You are in for a treat. Roll your own bearing pressure. By the way, reassembling the rear hub is not covered in the P11 manual at all.

Final adjustment is done after you drive or press the bearings into place close to where they need to be. The inners butt up to the spacer #8 between them. With the circlip in place holding the outer race from moving out on the drive side, the speedo side bearing is pushed inward from the speedo side by the threaded part #1 in the image below. Basically, you have to fake it till you make it.

Maybe Knut has some science to cover reassembly of the rear hub bearings. All I have is fake it magic.

The p11a rear wheel


The bearing adjuster is locked onto the hub with lock ring #2 and drives the speedo.
 
What is #4? Do you have a page that says what each piece is?

Yeah, I should have taken a wider shot.

#4 is a rubber seal. Book says Seal for bearing.

The p11a rear wheel


No part numbers in the P11 manual. You need the White Master Parts List 1966-1967-1968 for 650SS Atlas N15CS P11 P11A G15CS G15CSR G15 Mark II parts book.
 
could someone please measure the distance from the outside of the speedo drive and the flange on the swing arm where the axle fits through. Thanks.
 
Usually tightening tapered roller bearings involves spinning the wheel slowly as you torque the castle nut to a certain torque well beyond the final torque number. That is to take all the play out of the tapered bearing and seat the race all the way home. Then you turn the castle nut backward until its free of the assembly and use a much lower torque setting while spinning the wheel slowly to feel for drag to achieve the final torque setting. If the wheel drags when you tighten it, back it up and tighten again stopping short of where it was dragging.... You don't want to be too tight because the bearing will heat up and have a short life. It's not that hard to do correctly with a little understanding of what you are trying to achieve and knowing the common technique that almost all tapered roller bearings employ to get the proper alignment.... It's doesn't seem like a very scientific process compared to a nut with a torque value, but it is a tapered bearing, so even slightly too much torque is not good unlike any other thing you may tighten...
 
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