Early Norton hub conversion

mdt-son

VIP MEMBER
Joined
Jan 19, 2012
Messages
1,936
Country flag
Hi

Has anyone converted the early bolt-up rear hub and drum into a 3-bearing arrangement as per 1971-74 Commando?
I think it would improve stiffness of the sprocket/hub assembly a great deal. Any views on this are welcome.
Removing the protruding bearing boss at the drive side also makes the wheel more manageable when a tyre change is due.

- Knut
 
I have done this on a featherbed and the goal was to use an already laced-up 19" wheel and drum assembly I had. You have to change out the whole setup. I liked the change in handling and of course the ease of changing wheels. But for some reason I no longer remember I went back to the stock bolt-up setup. Maybe it was beause everything else about the bike appears original or maybe it was for general tire selection or maybe it was because I got a deal I couldn't pass up on a new Metzler ME88 which is still in my store room. I changed it out for a K-70 because of the amount of gravel I ride on. That was not a good move for riding on pavement and the K-70 isn't all that much better in gravel. I'm not sure what 19" rear tire I'd use if I went back to the quick-change setup. I heard Avon will no longer make motorcycle tires so there's one less choice now. No more roadrunners.
 
Thomasa said:
I have done this on a featherbed and the goal was to use an already laced-up 19" wheel and drum assembly I had. You have to change out the whole setup. I liked the change in handling and of course the ease of changing wheels. But for some reason I no longer remember I went back to the stock bolt-up setup. Maybe it was beause everything else about the bike appears original or maybe it was for general tire selection or maybe it was because I got a deal I couldn't pass up on a new Metzler ME88 which is still in my store room. I changed it out for a K-70 because of the amount of gravel I ride on. That was not a good move for riding on pavement and the K-70 isn't all that much better in gravel. I'm not sure what 19" rear tire I'd use if I went back to the quick-change setup. I heard Avon will no longer make motorcycle tires so there's one less choice now. No more roadrunners.
Click to expand...
Avon exiting the motorcycle tire market? I have not heard that.
 
I have converted all my pre-'71 Commandos to the cush drive hubs. It requires changing the hub with bearings and spacer, and the drum . I use the three hole hub cover to retain the appearance of the early wheel.
 
Ron L said:
I have converted all my pre-'71 Commandos to the cush drive hubs. It requires changing the hub with bearings and spacer, and the drum . I use the three hole hub cover to retain the appearance of the early wheel.
Click to expand...
OK, that's the easy way. There are some deficiencies in the design of NM19689 (the early hub), and I want to explore if a bearing arrangement similar to that of 06-2063 (the cush drive hub) will work. At the same time I want to do away with a flaw in the design of the later hub. The result will be a 3-bearing hub/brake drum similar to the AMC 1963 QD type of hub which is a very good design in my view (it looks unsightly though). The looks of NM19689 will be preserved though.

- Knut
 
Last edited:
Do you have a philosophical objection to using a Japanese hub? I've seen racing Nortons using Suzuki GT750 or Honda CB750 hubs. Both are cush drive.
 
Junglebiker said:
Do you have a philosophical objection to using a Japanese hub? I've seen racing Nortons using Suzuki GT750 or Honda CB750 hubs. Both are cush drive.
Click to expand...
It depends on the objective. For some builds I want to preserve the looks of originality (cf. #4 above), for others I choose radical deviations. In this build, I chose to retain the original clutch and therefore don't need a cush drive hub.
In a future step, I may change the primary drive and clutch (e.g., adopt a Phil Pearson clutch). Rather than using a japanese rear hub, I'd then select Don Pender's excellent rear hub.

- Knut
 
Last edited:
You must log in or register to reply here.
Back
Top