Author Topic: removing rear wheel bearings  (Read 663 times)

Online RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 5059
  • Karma: 48
Re: removing rear wheel bearings
« Reply #15 on: 25.05. 2019 22:03 »
GB,

Yes, I understood you to me vertical.

Swarfy,

I found the related diagram in my parts book. Of course, I hadn't paid attention to the plunger diagram (having two swingarms). So, I guess the bearings don't press onto the plunger tube. Does that mean the tube is there to set the horizontal distance between bearings? If not, this brings me back to why it is needed at all, and again, I'm thinking grease.  With the tube in place grease is not required to fill the entire inside volume of the hub and (he said repeating himself, hoping to stumble on reality) the notches are required to allow grease to reach the balls (truly a quotable statement).

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020 (if it's not cancelled and we are free to move about by then). Watch website at https://www.gentlemansride.com for details.

Online Greybeard

  • Jack of all trades; master of none.
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 6167
  • Karma: 35
Re: removing rear wheel bearings
« Reply #16 on: 25.05. 2019 22:46 »
GB,

Yes, I understood you to me vertical.

Swarfy,

I found the related diagram in my parts book. Of course, I hadn't paid attention to the plunger diagram (having two swingarms). So, I guess the bearings don't press onto the plunger tube. Does that mean the tube is there to set the horizontal distance between bearings? If not, this brings me back to why it is needed at all, and again, I'm thinking grease.  With the tube in place grease is not required to fill the entire inside volume of the hub and (he said repeating himself, hoping to stumble on reality) the notches are required to allow grease to reach the balls (truly a quotable statement).

Richard L.
Ok.
Yes.
No.

Offline Swarfcut

  • Wise & Enlightened
  • *
  • Join Date: Oct 2018
  • Posts: 1082
  • Karma: 14
Re: removing rear wheel bearings
« Reply #17 on: 25.05. 2019 22:52 »
Rich..Spot on. The plunger spacer sits by the side of the inner races and is there to support them and so sets the distance between the bearings.
   On assembly of the plunger hub grease would be packed into the open bearings, and retained to a degree by the "stars". The grease nipple on the hub is really for show, as to get any extra grease to the races would mean completely filling the hub centre with grease and adding another drag factor. The stars do not obstruct the hub centre void completely, so grease can pass to the bearings.

   The same is true for the early S/A hub, but just loading grease to the bearings  is easier, without the obstruction of the dividing walls of the "stars".  Still takes a load of grease though, so here again modern sealed pre lubed bearings are a better choice.

  Service Sheet 212C shows a cross section of the Plunger Hub, Sheet 212D is the S/A, and this latter cross section does not show  a grease nipple.

 Swarfy.

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4540
  • Karma: 41
Re: removing rear wheel bearings
« Reply #18 on: 26.05. 2019 00:00 »

 Lots of wasted grease in either unsealed setup  *eek*

As I discovered, there's really no *successful* inter-changeabilty of any of the S/A and Plunger hub components....due to lack of knowledge, I originally used a S/A wheel even a Unit model chainwheel thinking I can change the sprocket only and not the brake-drum as well.... *pull hair out* (48T was no fun either)
 I had in mind to mention the spacer with the scalloped discs, but brain ran out of steam.
  I also discovered that it's imperative to best ensure that the scalloped discs are outside the rivets and well clear (they can accidentally move if knocked), as the disc remains stationary so the axle and the hub spins around it but if the discs are in or close to the 'same plane' as the rivets, *eek* will be a crash/lock-zone...

  gotta go
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Online RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 5059
  • Karma: 48
Re: removing rear wheel bearings
« Reply #19 on: 26.05. 2019 00:05 »
GB,

Yes, I understood you to me vertical.

*lol* *lol*

Laugh-out-loud typographical error. *red*
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020 (if it's not cancelled and we are free to move about by then). Watch website at https://www.gentlemansride.com for details.

Online ironhead

  • A's Best Friend
  • ***
  • Join Date: Feb 2019
  • Posts: 166
  • Karma: 0
Re: removing rear wheel bearings
« Reply #20 on: 26.05. 2019 04:19 »
GB,



Does that mean the tube is there to set the horizontal distance between bearings? If not, this brings me back to why it is needed at all,

Richard L.


  Hi Richard,
The tube is there so when the axel is tightened it doesn't try & force the bearing centres away from the outer races thereby ruining them. ( but you already knew that *shh*)
SA