How do you mount a speedo drive on a Dayton wire wheel hub?

[Reno Speedster]

I told like to mount a speedo drive on a Dayton wire wheel hub and am looking for ideas on how to do it from folks who have. I have the hubs and a good Stewart speedo drive.

[Dan McEachern]

Buffalo hubs (not all) have three tabs that protrude out from the inner edge of the hub to mount the road wheel using three machine screws. Seems Dayton hubs may not have this feature, but you could make up three tabs and tig braze the tabs on your hub- In the picture below you can see one of the mounting tabs behind the road gear. Another method- Stewart made a road gear with about a 3" diameter center to mount on year? a Ford hub that had a machined feature on the inner edge to mount a road gear- locate one of these and machine the inner edge of the Dayton hub to clean up and then make a spacer to mount the road gear that way. Sorry, this picture is not the best, but you can see the mounting tab, and this road gear is the one with the small center hole to locate it on the hub.

[Reno Speedster]

Thanks Dan. Those are good options.

[Russ_Furstnow]

I have a set of Dayton wire wheels, and the Stewart road gear that fits the wire wheel hub is #8685. There are no "tabs" to screw the gear to, BUT the hub is machined to accept the 8685 gear so the runout is perfect. The gear and hub are nearly a press-on fit. I hope this helps. Russ Furstnow

[Dan McEachern]

Russ is showing the same road gear as in my picture. It would still be possible to drill and tap the hub flange and use long screws to hold the road gear afainst the hub if your Dayton hub has the machined shoulder, if not then simply machine the hub smooth and make a spacer ring if necessary to center the gear.

[Reno Speedster]

Thanks Russ. Was the friction alone enough to properly mount it?

[Russ_Furstnow]

While there was some friction, there will need to be something more to provide a tigher fit or screws to the gear. As Dan mentioned, you may need to braze or weld on some tabs to screw the gear to the hub. Russ

[Kevin Pharis]

Those tabs really complicate the manufacturing of new hubs, so I leave them off. To add that capability I make a ring that shrinks on to the hub. Brazing or welding will likely cause distortion of the bearing bore, but I have found that a .002” shrink fit is enough to retain the speedometer gear without distorting the bearing bore

[Reno Speedster]

Thanks Kevin, that looks like a good way to go. Maybe add some green loctite stud and bearing mount as well.

[Allan]

Might the firm fit of the gear be supplemented by the use of scotch screw or two to act as a positive lock to hold the gear in place?

Allan from down under.

[Reno Speedster]

Allan, my Aussie to Yank dictionary failed me. What’s a Scotch screw?

[Joe Reid]

It seems to be a screw with a 3M adhesive product applied to the threads, Scotch trademark.

[Allan]

A scotch screw is used to hold fixed components in place. It involves drilling a hole in the interface between two components, tapping a thread in the hole,and screwing a screw/bolt into the hole. In this application, it would stop the gear turning on the hub, at the same time stopping it from migrating off the hub. One might do. I would use two, diametrically opposite each other. If clearance is a problem, the screw could be a grub screw with a hex internal drive.
I used this method to adapt a fat man steering wheel to one of my T models.

Allan from down under.

[Reno Speedster]

Thanks Allan. I have seen that done but never heard it called that. That would keep it from rotating. If the plate used for the tabs was thick enough, it might be possible to achieve the same effect using set screws threaded through the side of the plate and bearing on the hub. This would obviate the need to modify the hub itself. I try to limit irreversible alterations to rare original parts. Though I am happy to do it to common ones for the Speedster.

[Allan]

Morgan, it not only stops it from rotating, it also stops it migrating sideways off the hub. Two screws would remove a total of one hole in the hub. This is easily filled later, if needed.

Allan from down under.