Topic: REAR WHEEL BEARING REMOVAL & RUBBER BABY BUGGY BUMPERS

[750duo]

1973 CB750 K3

Removal of REAR WHEEL BEARINGS
& WHEEL DAMPERS (Rubber Baby Buggy Bumpers)

My Problem: I wish to replace the 3 bearings AND REUSE THE HUB.

(Yes, I am afraid to just get a big hammer and beat on it.) I have looked on the forum and in the greenspun archives. Their have been posts about “just drive one out by beating on the opposite side and then turn it over to do the other side“. This may work for the front wheel (I have not got there yet) but from the Honda Manual diagrams, this does not look like it would work since there appears to be another bearing retainer for the bearing on the drive side hub.

Referring to the CB750 Honda manual pg .136 Fig. 13-14 (See diagram below)

I have removed the bearing retainer[28] in the final drive flange[24]. I have removed the bearing[8] on the brake drum side and the rear axle distance collar[21] (spacer?).

I can now see the inner bearing[22] in the hub[9]. 

Questions:
Is there really a bearing retainer[23] that holds the inner hub bearing[22].
Should the final drive flange[24] come off the hub prior to removing bearing retainer[23] and the inner bearing[22]  If so, How? (Big hammer, drift pin, $150 special Honda CB750 final drive flange puller only usable once, 20# Sledge Hammer, etc.)
Is the sleeve[25] holding the final drive flange[24] or is it held by the wheel dampers [18&19](rubber baby buggy bumpers).

Any help would be appreciated

Thanks, Tom

[Paul]

24 to 29 shoud come off in one piece
(correct me if I'm wrong) but 24 is only pushed in and often can be lifted out by hand, sprocket an' all
or some gentle leverage...without breaking the casting.
remove 23 and then 22 & 8 will push out from opposite sides.
Kinda difficult to get an edge against the outer race of the bearing from the opposite side while 21 is in the way.
but looks like you've got 50% out already.

Hope this is some help.

[750duo]

24 to 29 shoud come off in one piece
(correct me if I'm wrong) but 24 is only pushed in and often can be lifted out by hand, sprocket an' all
or some gentle leverage...without breaking the casting.
remove 23 and then 22 & 8 will push out from opposite sides.
Kinda difficult to get an edge against the outer race of the bearing from the opposite side while 21 is in the way.
but looks like you've got 50% out already.

Hope this is some help.

PAUL

Thanks for the reply

I agree that it looks like the whole final drive assembly[24]  SHOULD  come out easily - but I have been unable to get it apart using moderate force.  It may be just the fact that no one has had this hub apart for 33 years.

Tom

[Paul]

Pour a gallon of WD40 (easing oil) over it and check back tomorrow.
Someone else here knows....they're just not awake yet. (please hold  )

[techy5025]

The entire sprocket assembly will pull out of the hub as one piece. What is probably holding
it is the o-ring that goes around the inner hub and prevents grease from getting to the
bumpers.  If you find out how to easily remove the bearings, I would love to know...without
destroying them and the hub of course.

Jim

[2wheels]

Anyone please
The O ring, as shown above (item 16).  I need one for a Ko , 1969 rear wheel. cb 750.
Any sugestions welcomed.
Brian

[techy5025]

The Honda part number for the o-ring oil seal that you want is...

91258-300-013

I think I got mine from Service Honda.

Jim

[2wheels]

Thanks
For the part number, I've ordered one and should have this week.

Also for the expanded picture of the wheel which is the same as what my bike is.  But NOT the same as the dealer has for a 1969 CB 750 and NOT the same as some web sites publish for a 1969.
I'm not sure why this is 

Brian

[techy5025]

Brian,

At some point in the build of the K0-1 they made the four bolts that hold
the sprocket on part of the hub...instead of four individual bolts inserted from
the back of the hub.  They also changed from a two holes connection to the
brake side to four....and later the dampers changed...not sure when.
And they added a "chain catcher" to the outside of the sprocket.

I only have the early K0-1 parts manual so in later years I'm sure there
were other changes.

Glad you were able to get it apart...I had the same problem.

Jim