Rear wheel bearings

Hi all - at the recent MOT for my 1974 Mk2A Commando I was issued an 'advice note' that the rear wheel bearings are 'tired' - this was a warranted comment as there is some play in them. I've never tackled the wheel bearings on a Commando - any tips ? Do I simply need to purchase the two bearings or am I likely to need any other parts ? My Haynes manual is rather simplistic and vague - - .



Cheers,

mwoo said:

Do I simply need to purchase the two bearings or am I likely to need any other parts ?

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If you intend to fit 'open' bearings then the felt grease seals and any retaining washers obviously need to be in good condition, which maybe isn't so important when sealed '2RS' bearings are fitted.

mwoo said:

My Haynes manual is rather simplistic and vague

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Then use it in conjuction with the factory manual info (section H).
http://britmoto.com/manuals/Manuals/750_man.pdf

Most the struggle is to get the peened metal plate felt seal cover out of blind no edge gap bearing bore to get to bearing. Next hardest is keeping all the nitpick parts in order. I watched DynoDave do almost impossible cover removal task by flash light, strong drift wacks and tiny picks, knife point, with his nose almost touching the drum. In a shop could drill out and hook out stamped cover. Thank goodness don't need that with a sealed bearing. Double row available sealed.

Other wise its standard heat and bump-drift to get the bearings out and new sealed version in. Norton vendors know and stock upgrade bearings and can detail any issues to be aware of. There is definitely increased risk of axle fracture with loose bearings and the stress riser fatigue cracks may already have started.
Magna flux or replace for peace of my mind.

There are photos and diagrams in this thread:

rear-axle-puzzle-t6077-15.html?hilit=axle

You will need a special wrench to get into the bearings on the speedo drive side as there is a lock ring. I made mine from a piece of 1-1/2 pipe. They are not real hard to change, but there are lots of pieces in there so keep track of them and you will be alright.

Russ

A sealed double-row rear wheel bearing, 06-7688, is a plug-and-play replacement for the open OEM part and DOES NOT require machining of the rear hub. I got mine from Walridge, but Mike tells me that Norvil carries them in the UK. They mic'ed out at slightly less than the OEM bearing cage width, and fit perfectly. Same for the front double-row bearing. The single row wheel bearings have been available in sealed form for some time. I believe that these parts are sourced in eastern Europe.

rick in seattle said:

A sealed double-row rear wheel bearing, 06-7688, is a plug-and-play replacement for the open OEM part and DOES NOT require machining of the rear hub. I got mine from Walridge

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do you have an actual bearing number for that , I looked at it a while ago and was only able to do it with a wider bearing.

rick in seattle said:

A sealed double-row rear wheel bearing, 06-7688, is a plug-and-play replacement for the open OEM part and DOES NOT require machining of the rear hub.

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The 06-7688 double-row bearing is the brake drum bearing which may or may not be required. The rear wheel bearings are both 06-5542 (6203).
http://www.nortonmotors.de/ANIL/Norton% ... 20&Part=43

Les,

The double-row bearing I was refering to resides in the cush of the Mk3. Sealed replacements for this bearing are commonly oversized in width and require some disagreeable machine work on the hub. Walridge's part, 06-7688, is a perfect replacement for the OEM double-row open-frame bearing (same part number) with no machining required. The left and right single-row rear wheel bearings, 06-5542, are available from many suppliers as sealed bearings. It is only the double-row bearing that can cause some grief when searching for a sealed replacement.

Mike at Walridge is aware of this problem of sealed bearing replacement in Nortons. He told me some time ago that he sourced 06-7688 through Norvil. I don't have any personal knowledge of Norvil parts, as my needs in the states are met through Walridge. The key dimension is the bearing width.

rick in seattle said:

The double-row bearing I was refering to resides in the cush of the Mk3.

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The MkIII cush unit is in the hub, the double-row bearing is in the MkIII sprocket (which is maybe what you meant?).

rick in seattle said:

A sealed double-row rear wheel bearing, 06-7688,

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If mwoo's MkII model's wheel bearings are shot then there may be no reason for him to change the double-row (drum/sprocket) bearing as it isn't one of the "wheel" bearings.