P11 neck bearings, what to do?

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I have looked at a few possibilities for my P11 project's neck. Here is the problem. I want to run a one inch Sportster neck on my Norton/Matchless frame. The original style bearings look feeble to me and will need custom races made for the triple clamp. I would prefer to have Timken style bearings put in but with the 1" neck there really isn't enough room.
One option would be to machine off the race holders from the neck and sleeve down to accept Harley cups that I have. Another more drastic option would be to machine off the neck completely and weld on neck from MKIII with matching numbers and paperwork to donor engine. This could be double bonus of sealed bearings and no hassle registration. I'm not bothered by the idea of molesting the frame, all unused tabs and what not will be shaved off. This will be built to be a runner and to my taste. There are enough of these things in museums for those that want to see originals.
My question to Granpaul, Ludwig, Ironjohn, and all others that have dealt with the AJS/Norton/Matchless neck is what did you do?
How good/bad is the original set-up?
Any bearings that I am unaware of that would allow the 1" neck shaft to reside in the stock casting without hogging the casting to the point of weakness.
Thank you for sharing your wisdom and experience.

Will
 
Interesting, P11s survived desert racing in the Baja 500. I would think that was sturdy enough.
 
Cookie said:
Interesting, P11s survived desert racing in the Baja 500. I would think that was sturdy enough.
They probably got stripped and rebuilt on a yearly basis as well. Wheelies and jumping are hard on the neck. I don't like having to do the maintenance.
P11 neck bearings, what to do?

Not much surface area there. The bike is apart awaiting rebirth and I would like to improve it. Changing out ball bearings for tapered is pretty common practice if the bike is going to be used and abused. I've done it to other bikes. If Commandos came with this style neck bearing I'm sure a kit would exist to replace it. Like I said, I'm looking for comments from someone that actually has one or the same style neck and uses it.

Will
 
I had a heck of a time locating new races for my Ranger - rare with the Norton suppliers. If they weren't so badly worn, I'd have re-used them. Looks like the original owner never re-greased them.

Seems they're the same races used on most AMC bikes from '41 on. There are oil seals inside the neck and a grease fitting in the head, so I would think regular greasing would allow 15000+ miles between teardowns.
 
BillT said:
I had a heck of a time locating new races for my Ranger - rare with the Norton suppliers. If they weren't so badly worn, I'd have re-used them. Looks like the original owner never re-greased them.

Seems they're the same races used on most AMC bikes from '41 on. There are oil seals inside the neck and a grease fitting in the head, so I would think regular greasing would allow 15000+ miles between teardowns.

Thanks for the reply. I'm starting from zero so will have to get all new races and balls. Then machine adapters for the triple clamp. I was just hoping that there was a quick and easy way to get a better set-up.
 
The original races were:

01-2620 - handlebar lug race
00-0806 - frame races (2 required)
00-0805 - bottom yoke race

28 - 3/16" ball bearings in each pair of races.

Atlas used a similar set-up, except with 1/4" ball bearings (18 in each race pair)

I found my races at AMC Classic Spares, in Britain.
 
Thanks Bill,

I'm still undecided on what to do but will keep those part numbers in case I take the easy way out and keep the factory set-up.

Will
 
Might depend on waht you want to use it for. When I was a kid I had an N15CSR up in Maine (I know this is stupid but I was a kid in the country) and I used to fire road and run it down the old railroad track gravel road from Greenville to Shirley at very high speeds. A heck of a way to treat a factory cafe racer. I checked the neck every winter and never had problems with the original bearings. If you are going to ride it at more than 80 mph on dirt roads you may need rollers.
 
I plan for up to 100mph on dirt and bridge jumps that should be 20-30 feet long and a couple feet high. The usual ride in anger away from Joe public that leaves me feeling spent and relaxed afterward. Some light off-roading will be done and we will see what the 850 in it's new home can do on the road on the odd Sunday ride with the guys. It's replacing my KTM 640 that the wife made me sell when I bought the Superduke.
 
You might do well to toughen it up then, save you going back in to fix it later. Check to see if All Balls has a kit, I'd think that would be too low demand though.
I put rollers in one of my bikes last winter with no kit and it was kind of annoying working out seals and spacers.
 
Cookie said:
Check to see if All Balls has a kit, I'd think that would be too low demand though.

Thanks for the All balls idea. I don't think they will be able to help but they may be a good resource for other builds.

Will
 
My ultimate solution was to remove the cup holders, sleeve the neck, fit H-D neck cups and weld.
what it looks like now.
P11 neck bearings, what to do?

P11 neck bearings, what to do?

P11 neck bearings, what to do?


I'll start a build thread after making some more progress.
Waiting for parts, machine time, time, money, etc. Will be a slow build.
 
Go to a bearing supplier (GBS??) and ask them if they have tapered roller bearings with the right size for the Norton neck and the triple trees you want to use, there is a good chance they have the right bearing on hand or they can order, this will save you much machining and or welding.

Jean
 
Thanks Jean,

The last photos are of my frame after I did the work. There was no easy bearing swap with the AJS/Matchless/Norton neck with 1" neck diameter for the triple clamp shaft. The casting would have been hogged out to the point of being too weak to do it's job. I sleeved the neck and welded new cups for Timken"s. It's done now. It's strong and almost looks like it was made that way originally.

Will
 
willh said:
Thanks Jean,

The last photos are of my frame after I did the work. There was no easy bearing swap with the AJS/Matchless/Norton neck with 1" neck diameter for the triple clamp shaft. The casting would have been hogged out to the point of being too weak to do it's job. I sleeved the neck and welded new cups for Timken"s. It's done now. It's strong and almost looks like it was made that way originally.

Will

Sorry, I missed the fact that it was done. Obviously you did the job too good, it is hard to notice anything had been done.

Jean
 
willh said:
Thanks Jean,

The last photos are of my frame after I did the work. There was no easy bearing swap with the AJS/Matchless/Norton neck with 1" neck diameter for the triple clamp shaft. The casting would have been hogged out to the point of being too weak to do it's job. I sleeved the neck and welded new cups for Timken"s. It's done now. It's strong and almost looks like it was made that way originally.

Will


I wonder how you kept the parts exactly in line when welding? Seems to me that this must have been very very difficult, and may have been an awful lot easier to make a completely new headstock to take modern front forks suitable for off road riding? If the bearing houses arent perfectly in line, then a tight spot in the steering may result, and I cant see any way to overcome this, without putting the frame into a jig, and fitting a new headstock. Hopefully it wont have a tight spot though, and there will be no need to deal with the problem.
 
Carbonfibre said:
I wonder how you kept the parts exactly in line when welding? Seems to me that this must have been very very difficult, and may have been an awful lot easier to make a completely new headstock to take modern front forks suitable for off road riding? If the bearing houses arent perfectly in line, then a tight spot in the steering may result, and I cant see any way to overcome this, without putting the frame into a jig, and fitting a new headstock. Hopefully it wont have a tight spot though, and there will be no need to deal with the problem.

I sleeved the neck with a very light press fit, while keeping in mind the brittle casting, and the cups were lightly pressed in and bottomed in the full length sleeve. The triple was installed, tightened, and checked for tightness. The cups were tacked and then triple was removed before MIG-ing the bottom. Cool down then top, cool down then bottom, etc. to get the thickness desired.

I was somewhat concerned about the neck casting properties and brass. If I were to go another route, IE cutting the neck off, I feel that the whole casting would have had to come off and tubing lengthened, etc. I seriously considered it but tried this first. Happy to report that there are no tight spots so it worked as hoped. If it had failed then the next step would have been a new neck farther down the road.

The machine time was free. I had to pay for the welding because I didn`t have the free time at work but wanted to have it done anyway.

I`m on a budget. I`d love to have a frame jig at home and a tig, lathe, milling machine, etc.... Doing what I can with what I have at my disposal...

Will
 
Thats fine then................I would have tended to TIG braze a job like that though, as there is far less chance of distortion. If the frame has a cast headstock, then its investment cast steel and pretty durable. It is worth bearing in mind if you are doing any welding in or around investment cast frame lugs etc, that it is possible to melt the braze joining the lug to the frame tube, and this can obviously have very serious consequences!
 
Carbonfibre said:
.... that it is possible to melt the braze joining the lug to the frame tube, and this can obviously have very serious consequences!
I cleaned out the neck of all brass that could have made it to the welds. We took are time and kept the temps down.

There are areas of the frame that are dripping with brass. They didn't seem to bother with wiping the extra off at the factory.
 
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