Advice - MK3 hub to earlier Commando's.

Hi Guys,

I have an MKIII wheel here that came with my Commando project I'm in the middle of resto-modding. Unfortunately I do not have the cush drive for it and they look to be scarce on the market. I have found a couple places to buy them for over $100. I was considering running the rear disc on my '73 but I'm beginning to think that it may not work out. Correct me if I'm wrong but the OD of the disc hub spindle is larger, right? Unfortunately my swing arm has already been coated (so I don't want to widen the drop outs) and my swingarm is already attached to the cradle (so I don't want to tear that down to replace with a likely expensive swingarm). Anyway, if anyone has adopted an mk3 wheel to an earlier swingarm I'd appreciate the advice. if not guess I can make a buck off the wheel.


Mario

383wss said:

Correct me if I'm wrong but the OD of the disc hub spindle is larger, right?

Click to expand...

Yes, it's 17mm.

Thanks, L.A.B. much appreciated. if I had the mk3 spindle I would have checked myself.

I inherited a MKIII rear wheeled 73 and besides studying it, I see it CAN be done....
But the main question is why?
I will likely be parting the bike out, including an extra MKIII WM3-18 akront :roll: :roll: :roll: I'm ashamed to say I built the wheel.

dynodave said:

I inherited a MKIII rear wheeled 73 and besides studying it, I see it CAN be done....
But the main question is why?
I will likely be parting the bike out, including an extra MKIII WM3-18 akront :roll: :roll: :roll: I'm ashamed to say I built the wheel.

Click to expand...

One reason would be to end up with a proper cush drive rather than that thing with the hard little nubbins attempting to be a cush drive?
I'm not seeing anything to be ashamed of in building an 18" akront wheel for a Commando. Even the really cool kids at school shouldn't give you grief over that.

Glen

I tend to agree with dynodave's assessment. Having done this conversion with my '74 Norton, it seems all I accomplished was adding unsprung weight until I converted it to a Brembo disc and caliper from a Ducati 900 SS. I had an extra Mk3 swingarm, sprocket, speedo drive, and rear wheel, so the cost was minimal. Still, I would not do it again.

Perhaps it's not one of those night and day type mods, but your gearbox and other driveline items are likely going to thank you over the long term.
That sort of thing (better cush, reduced shock loading) is really important but sometimes hard to quantify.

Glen

I think the "added" cush drive is oversold and over glorified. The reduced shock load from the rear drive versus the source of the shock load = engine pulses from a 20+ lb flywheel and another 10-15 lbs of chain and clutch basket into those tiny gear faces.
Internet forums have next to zero memory, and even less "search engine" capability/use, but if I repeat the story one more time people will think I have an agenda, or have stock in belt drive manufacturers.
I have shared the Carl Hockensen belt drive story many many times since the late 80's and if people care to not listen, which seems to be often, then that is at their peril.
If you want to hear it again, see me at the rally next week. I'll be at NENO area site G9, assuming I make it there.

FWIW....I think that fellow forum member "matchless" had the right idea with regards to rear wheel set up. Try doing a search for his build thread , 920 pictures.........use "superb cush drive" as key words for the search. He laced a suzuki 550 hub up and fit it on his build. There is no wonky offset , excellent cush drive , easy to match a disc to and I believe it looks right on the commando with it's finned or ribbed center casting which is similar to a rear drum brake model Cj

This is all good, it means I am safe to park my MK3 without fear of someone stealing the rear wheel for their lesser Commando.
I like the look of the conical rear MK3 hub, especially when polished. Years ago when removing the wheel for the first time, I remember being impressed with the ease of using the QD feature as compared to some other bikes of that era.
The cush drive is just plain skookum.
In using the search feature, I have learned that the earlier cush drive was neither cushy nor strong. I can see why Norton made a change

As far as the offset goes, it was easy enough to do when lacing up a new rim. Many makes/models have some sort of offset to deal with.
The disc is a bit heavy, but the positive on the heavy solid disc is that it tends to stay very flat.


Glen