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Hello everyone,
Still working on the 1970 450 Scrambler and I recently completed lacing the front wheel and noticed the center hub was wobbling but trued the wheel and thought everything was okay. When I replaced the brake covers and axle I discovered that there is about 4mm of movement on the hub so that the hub is oscillating all over the hub covers. I assume the bearings are out of alignment, I have removed the left bearing but cannot figure out how to remove the speedometer drive gear to remove the other bearing. It seems to be capped by the Speedometer gear, I am way over my head here, not even sure it is the bearings. Any thoughts? They would be greatly appreciated.
Best regards!

Sorry, we need more clarification, when you talk about the Speedo drive gear, are you talking about the hub plate that covers the gear, or the gear itself? The gear fitted to the hub does not need to come off to replace the bearings.

Does it look like this?



This is a 160 Monza hub, but likely the same arrangement?
In this case, the bearing comes out without disturbing the speedo gear.
There is just two bearings and a spacer in between.

Thank you guys so much. All I found in the manuals and online indicated the speedometer gear as a single piece. Visually and magnetically it appeared to me as I had imagined. Looking closer after your comments I was able to pop off the washer and expose the bearing as you can see in the images below. I am also adding a link to the videos showing the hub wobble which I continue to assume is a bearing issue. Recognizing my ignorance, any insights would be greatly appreciated.

Cheers!



https://ccrarchitects-my.sharepoint.com ... A?e=BWgxvh

Hmmmm, were the bearings tight in the hub? All you can do is replace them and see if it cures the problem, otherwise, I wonder if the hub has been in a smash and is bent? What do others think?

It looks like the hub is distorted to me and that the central bearing housing is not concentric to the hub outer, maybe it's suffered a large side impact.

That well may be the case, I have new bearings on the way and will see what that does.
The rear frame was bent and had about a half inch or closer to 1.75 cm difference on the rear shocks. It is in the process of being straightened now. It appears she had a nice abrupt exit from the original owner.
The rim and original spokes looked fine on disassembly so it is strange that the hub was bent and the rim is straight, I will work on it this weekend and let you know. Thank you all for the help.
Rebuilding a pile is a an interesting and informative journey...

Yep, it is a warped/bent hub.
New bearings in tight and the same wobble.
I am in the market if anyone has a one in good condition!
Thank you all for the assistance and attention.

There are a lot for sale on eBay, especially from Spain, but postage is a problem.

Also in France where Leboncoin is a good site, for example: https://www.leboncoin.fr/equipement_moto/1567911423.htm
You might find delivery charges from France are not as steep as expected.
Good luck!
Al