Gearbox Mainshaft bearing, timing side

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Atlas Commando

Atlas Commando

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Quite a year! A couple of weeks back I finally got my engine cleaned up from my garage fire back in January. There were numerous other personal setbacks, none of which were due to the Covid-19 issues, but anyway.... with the engine set up with all new seals, soot stains removed and a nicely polished timing cover (again), it's finally off the bench and I've moved on to the gearbox.
The bike hasn't run since 1985, so I obviously need to go through everything. The good news is that the gearbox and gears are in excellent condition. I barbequed the cases until the bearings fell out, and I've received almost all of the new bushings, bearings and springs, but I need to source a new mainshaft bearing for the timing side. I've searched the forum and have not found a good, solid manufacturer/part number combination for the new one. The Norton part 04-0099 is backordered with my favorite supplier, so I plan to take the old one to a local bearing shop to see if they can match it. I want to get the gearbox fully assembled and off the bench so I can move on to stripping the frame. (very small shop)

I would really appreciate any input on a good replacement bearing number, whether for SKF or maybe RHP. I don't want to be fully at the mercy of the parts counter guy. Thanks for your time!
 
The bearing I have in hand says RLS - 5RS (I will remove both seals)
I'm not sure the AN bearing I installed had a number on it.

Gearbox Mainshaft bearing, timing side
 
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That's the basic bearing yes...
Would love to know if the ball cage is:
thin folded bent tab brass cage or
spot welded brass cage or
peened riveted brass cage or
peened riveted steel cage (my preference)
spot welded steel?
 
Atlas Commando said:
Quite a year! A couple of weeks back I finally got my engine cleaned up from my garage fire back in January. There were numerous other personal setbacks, none of which were due to the Covid-19 issues, but anyway.... with the engine set up with all new seals, soot stains removed and a nicely polished timing cover (again), it's finally off the bench and I've moved on to the gearbox.
The bike hasn't run since 1985, so I obviously need to go through everything. The good news is that the gearbox and gears are in excellent condition. I barbequed the cases until the bearings fell out, and I've received almost all of the new bushings, bearings and springs, but I need to source a new mainshaft bearing for the timing side. I've searched the forum and have not found a good, solid manufacturer/part number combination for the new one. The Norton part 04-0099 is backordered with my favorite supplier, so I plan to take the old one to a local bearing shop to see if they can match it. I want to get the gearbox fully assembled and off the bench so I can move on to stripping the frame. (very small shop)

I would really appreciate any input on a good replacement bearing number, whether for SKF or maybe RHP. I don't want to be fully at the mercy of the parts counter guy. Thanks for your time!
Click to expand...
It's a common bearing (RLS5) available from just about any bearing supplier. If you want the one from AN, I have them in stock for $24 delivered to anywhere in the US.
 
Why don't I just order my bearing from you Greg? Bearings specs can be a bit of a minefield, at least for me. I'll get on line and place my order tonight or tomorrow. Now that I think of it, I also need wheel bearings and steering head bearings. I'll see what you've got for those part numbers.
 
Dyno Dave, you make a good point on the technical details of the bearing. Sometimes identical parts simply aren't. That can be a good thing. For example I did acquire an upgraded layshaft bearing based on what I've learned on this site. For the timing side mainshaft bearing I've never seen any reports about problems with it, so will be quite happy to put the 'identical' part in. I'll have a look at the cage on the new bearing and compare it with my old one. I have no way of knowing whether the 'as found' bearing is original.
Man, I love this site! We're all so anal!!
 
Atlas Commando said:
We're all so anal!!
Click to expand...

I think not all, all it takes is a trip to the bearing store for one non sealed RLS-5 at maybe $7 to $10.

The other bearings (steering head and wheels) are just as straight forward unless you want to use tapered rollers in the head or a wider double row in the wheels.
 
I bought a gearbox rebuild kit from rgm and just intstalled it. The main shaft sleeve bearing had metal shields with what looked like tiny holes. I emailed r and asked about removal of the shield on one side but never heard back. I put some gear oil on it and it looked as though after a long while some went through ? I just left it on there and put the box together. I hope I made the right decision ?
On another note : After I had it all together I started obsessing about whether I had a gear on the main shaft turned properly. ( a touch of ocd ) It seems to shift properly but ? Is it possible to have a gear reversed and it still shift properly ? I don’t really think so but there again what do I know. This was my first Norton gearbox overhaul.
 
Kthomas said:
I bought a gearbox rebuild kit from rgm and just intstalled it. The main shaft sleeve bearing had metal shields with what looked like tiny holes. I emailed r and asked about removal of the shield on one side but never heard back. I put some gear oil on it and it looked as though after a long while some went through ? I just left it on there and put the box together. I hope I made the right decision ?
On another note : After I had it all together I started obsessing about whether I had a gear on the main shaft turned properly. ( a touch of ocd ) It seems to shift properly but ? Is it possible to have a gear reversed and it still shift properly ? I don’t really think so but there again what do I know. This was my first Norton gearbox overhaul.
Click to expand...
IMHO the shield on the outside is good and the one on the inside not so much. Shielded bearings are factory greased and it will probably work just fine for a long time, but oil bathed bearings, again IMHO, are smoother and last much longer. On the other hand, if there is any crud in the gearbox or if any develops, the double shielded bearing is somewhat protected. BTW, there are sealed and shielded bearings - I don't know which you have. Here's something on the difference: https://www.bearingtips.com/difference-bearing-shields-bearing-seals/

So, I would say "you made your bed, now sleep in it" :)

One last thing. I worked on a bike with the primary and drive chains adjusted wrong and that made so much heat that it melted the bearing's rubber seals and the press-in seal that the previous owner installed resulting in hot gearbox oil all over the rear of the bike. I'm now not a fan of rubber sealed bearings in engines/gearboxes. I use the single metal shield sleeve gear bearing on all my gearbox rebuilds.
 
As Greg Marsh says, a 'shield' (Z) isn't the same as a 'seal' (RS) so oil will circulate through a shielded bearing.

AN's single shield bearing option:
andover-norton.co.uk

Motorcycle parts and spares for Norton motorbikes - Genuine Andover Norton Spare Parts - Andover Norton Motorcycles Parts - Original Andover Norton Parts

Motorcycle parts and spares for Andover Norton motorbikes: Andover Norton manufactures and supplies all Genuine Factory Spare Parts for Norton motorcycles built before 2002.
andover-norton.co.uk
Gearbox Mainshaft bearing, timing side


Kthomas said:
I put some gear oil on it and it looked as though after a long while some went through ? I just left it on there and put the box together. I hope I made the right decision ?
Click to expand...

The sleeve gear pinion completely shields the bearing with only about a 0.002" gap so a shield on the inside although unlikely to do any harm seems pointless.
Gearbox Mainshaft bearing, timing side
 
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So
That picture is the bearing I installed. Are those not tiny holes ? Are you saying I should have taken the metal shield off ?
 
Kthomas said:
So
That picture is the bearing I installed. Are those not tiny holes ? Are you saying I should have taken the metal shield off ?
Click to expand...
In a perfect world, you would have the metal shield on the outside and none on the inside. If you have both, just leave it - you will be fine.
 
Kthomas said:
So
That picture is the bearing I installed. Are those not tiny holes ?
Click to expand...

Yes, and there's also approximately 0.005" clearance between the shield and the inner race.

Seals and Shields

www.bearingworks.com www.bearingworks.com
"‘Z’ Type Shield – The ‘Z’ type shield is a metal shield that typically is non-removable after installation as is it pressed in. There is a small gap about .005 inches between the shield and inner race. There is no contact so obtainable speeds and torque are not effected[affected] as in a contact type seal. Lubricant leakage can occur and contamination can enter through this gap. They have fair dust resistance and poor water resistance. Shields are good to around 350 F.

‘RS’ Type Seal – The ‘RS’ type seal is a rubber seal that makes contact with the inner race. Most commonly made of Buna-rubber. They are removable. They offer the best sealing against contamination and lubricant leakage. Generally the speed rating is reduced about 35% that of the ‘Z’ type or open and torque is increased. Temperature range is 15 F to 220 F.[/b]"
 
I’m wrong
Both sides were shielded but I put some gear oil on the stop and it looked like some was going in but not much.
Damn, I really don’t want to redo that box but ?
L.A.B. said:
Yes, and there's also approximately 0.005" clearance between the shield and the inner race.

Seals and Shields

www.bearingworks.com www.bearingworks.com
"‘Z’ Type Shield – The ‘Z’ type shield is a metal shield that typically is non-removable after installation as is it pressed in. There is a small gap about .005 inches between the shield and inner race. There is no contact so obtainable speeds and torque are not effected[affected] as in a contact type seal. Lubricant leakage can occur and contamination can enter through this gap. They have fair dust resistance and poor water resistance. Shields are good to around 350 F.

‘RS’ Type Seal – The ‘RS’ type seal is a rubber seal that makes contact with the inner race. Most commonly made of Buna-rubber. They are removable. They offer the best sealing against contamination and lubricant leakage. Generally the speed rating is reduced about 35% that of the ‘Z’ type or open and torque is increased. Temperature range is 15 F to 220 F.[/b]"
Click to expand...
 
Kthomas said:
Both sides were shielded but I put some gear oil on the stop and it looked like some was going in but not much.
Damn, I really don’t want to redo that box but ?
Click to expand...

It should get enough lubrication with the shield in place so I agree with Greg that it isn't a problem.
 
Zz type - typically non removable after installation ?
Well - that settles that. F#$$&*%K
I ’m definitely not removing the bearing and if it’s not coming off since being installed I guess I’ll just run it till something gives.
This came in the rgm kit.
i knew I should have taken it off but then noticed what looked to be tiny holes and thought oh well. I then emailed rgm and never heard back and there was nothing in their notes that came with the kit.
Then I realized the bearing sits above the oil .
I think the reason we all love these things is due to the constant level of grief they impart upon us !
Ive been running a 750 for 25 years and maintaining it is taxing at times to say the least but when its right all is well with the world. That gearbox is next as I have never opened it up . It’s one of those jobs I’ve always ignored.
 
The Andover Norton kits come with an open bearing with a single shield (to the outside) bearing as an option (that you need to find via the attached part number)
There is small window of around 0.020" at the root of each sleeve gear tooth.

The only reason (already posted) I see to run an outer Seal in the bearing is some form of insurance should the case seal fail.
With the bearing seal the case seal would be running all but dry so then all but a dust seal (unless it wore out ?)
 
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