'71 Cush Drive - Hub to Sprocket not flush

Status
Not open for further replies.
elefantrider

elefantrider

Joined
Apr 6, 2013
Messages
1,446
Country flag
As far as I remember, these two mating surfaces should be flush. I am working on a bike which came to me with a large gap between them. Pegs do not go fully in. What could cause this?

'71 Cush Drive - Hub to Sprocket not flush

Uploaded a pic.
 
Last edited:
'71 Cush Drive - Hub to Sprocket not flush

I think I found the culprit. The hub was assembled wrong. Stepped washer sticking out too far. Should be flush as when compared to my other wheels.

Has anyone found any appropriate sized impact spindle nut socket to remove the hub lockrings? I am looking for a lockring peg spanner replacement tool which I can use with my 1/2 impact air.
 
Last edited:
for the speedo drive ring , use a c spanner, I wouldnt use an impact gun, you will end up doing more harm than good.
 
For a cheap easy tool I used a piece of flat steel, drilled two holes same distance apart as the lock ring and dropped two nails in ( cut to the appropriate length). 15 minutes and no cost, beat waiting for an ordered delivery.
 
I got it off using a brass punch which is not soft enough for the lockring, FYI. It was too tight but does not surprise me as the spindle was assembled with red loctite by the PO’s mechanic.
Looks like it has sealed bearings. The depth on the speedo drive side seems correct. Is there a shoulder on the hub to prevent the other side bearing from going in further, or is the spacer the only thing separating the bearings? Either the bearings are not correct or I need to shift everything to the speedo drive side a little.
 
Last edited:
'71 Cush Drive - Hub to Sprocket not flush


It looks like the bearing depth is determined by the hub. So I think the wrong bearing was used or an excess shim. Isn't there an issue with sealed bearings replacing stock, needing a modification to the REAR hub assembly?
Does the hub need heat to remove the bearing?
 
Actually, since it is a sealed bearing, can't it be run -at least temporarily - without the felt and the dished outer washer (06.3012)?
With the bigger sealed bearing, that would give me the clearance I need, allowing the hub to sit flush with the drum.
 
Last edited:
elefantrider said:
It looks like the bearing depth is determined by the hub. So I think the wrong bearing was used or an excess shim. Isn't there an issue with sealed bearings replacing stock, needing a modification to the REAR hub assembly?
Click to expand...

That's the double-row brake drum bearing (or bolted-up hub drive-side bearing) although a sealed bearing is available in the correct (16mm) width.

The 'cush' hub bearings should be the same (6203).
https://andover-norton.co.uk/en/shop-drawing/246/rear-wheel-drum-bearings#
[26]



elefantrider said:
Does the hub need heat to remove the bearing?
Click to expand...

Usually a good idea.

When refitting the bearings, follow the procedure in the manual. Fit the timing-side bearing first but only enough so the lock ring can be screwed in then use the lock-ring to set the bearing depth. Fit the bearing spacer with the long shoulder on the timing-side.
 
Last edited:
L.A.B. said:
That's the double-row brake drum bearing (or bolted-up hub drive-side bearing) although a sealed bearing is available in the correct (16mm) width.

The 'cush' hub bearings should be the same (6203).
https://andover-norton.co.uk/en/shop-drawing/246/rear-wheel-drum-bearings#
[26]
Click to expand...

Do you mean the cush drive side bearing is incorrect but the speedo drive bearing is correct. Or both are incorrect?
The drawing says they are both the same bearings, but lists a different PN for the brake drum.

I will post a picture of the brake drum side in a few minutes.
 
Mr. Rick said:
Looks to me like the "dished washer" 063012 is simply installed upside-down. The "dish" goes inward, toward the hub. Fire the guy who installed it.
And confiscate the air gun from anyone who wants to use it to install the lock ring.
Click to expand...

The dished washer looks to be installed the right way according to the drawing???

The previous owner had the bike costmetically restored by someone. Looked nice but didn't run.
I am going to get the correct wrench for the lock ring. Thought I had one around here. Replacement lock rings are not cheap!
 
Last edited:
Brake drum photo. Anything look out of the ordinary?
 

Attachments

  • '71 Cush Drive - Hub to Sprocket not flush
    FA6827DA-1A4E-44BC-A77D-820FDFA7B81A.webp
    29.6 KB · Views: 370
elefantrider said:
Do you mean the cush drive side bearing is incorrect but the speedo drive bearing is correct. Or both are incorrect?
Click to expand...

I don't know as you haven't said which bearings they are.


elefantrider said:
The drawing says they are both the same bearings, but lists a different PN for the brake drum.
Click to expand...

Yes, the two cush hub bearings are (or should be) the same (6203).

https://andover-norton.co.uk/en/sho...3-1rs-17-x-40-x-12mm-a2-435-04-0100-nm-17719-

The standard width cush hub brake drum bearing (item 46) is a double-row 4203.

https://andover-norton.co.uk/en/shop-details/17248/bearing-17x40x16mm-a2-436-nm17721-steel-cage
 
if you are using sealed bearings and why wouldnt you, then you dont need all the felt seals and associated washers cups etc
 
elefantrider said:
The dished washer looks to be installed the right way according to the drawing???
Click to expand...
The illustration is very poor, doesn't even resemble the actual part.
Illustration Part # 32 here: http://www.oldbritts.com/1973_g20.html

actual part picture here: https://andover-norton.co.uk/en/shop-details/15981

Either way, it shd be flush at the surface, and if it can't be done, something else is not right.

And yes, if you have sealed bearings, you wouldn't even need it.
 
Each Commando issued is somewhat different unique on the parts stack up in rear axle/hub/cush drive/speedo/spacer fitting - that famous vendors can straighten out as likely to need new parts to carry on anyway. So after taking in the details scope of mis matching laid out already can order up bolt up stack up and forget about it. Basically a double row sealed bearing and some fiddling of spacers fills does the trick long term but sometimes need a tad machining to get drum bore acceptance right. Make note of upgrade so next guy not confused on renewal. There's always a renewal or would be scrapped out.
 
Status
Not open for further replies.

Similar threads

Sergio
  • Locked
New MK2 rear cush drive hub
2
Replies
33
Views
5,781
1973x75
1973x75
madass140
  • Locked
Cush Drive Hubs
2
Replies
25
Views
1,730
madass140
madass140
Dances with Shrapnel
  • Locked
Not a "Cush" Drive
Replies
12
Views
2,062
Dances with Shrapnel
Dances with Shrapnel
H
  • Locked
Rear Brake, Hub & Cush Drive Issues
Replies
17
Views
4,723
ashman
ashman
D
  • Locked
cush drive hub bearing spacer
Replies
4
Views
852
dave M
D
Back
Top