Hi Norm
I haven't repaired a wheel like this ,just usually replaced the wheel.
I know there is a product called Rubbafix that looks good in the Video but no idea on how expensive it would be.
I have heard of someone that was going the mould some tyres up for the 24 but never heard if it worked.
If it was me I'd probably try holding the tyre on with Araldite as that will hold 75 kg and also fill the gap with Araldite,
I've used Araldite on black vinyl and mixed in a little black paint with the 2 part glue so it matches in a little better.
https://au.rs-online.com/web/p/fillers-putties/0692851https://vimeo.com/282732075I have had wheels like this that were drilled in the centre of the tread and every couple of inches a long self taper screws
down the rubber tread into the steel centre (on an angle so the self taper comes through the sheet metal.)
The head of the screw is below the tread in the tyre .
A cheap fix will look a little rough sometimes.
Not sure if anyone else has successfully repaired this problem without replacing the wheel and the wheels will still look standard.
Cheers
Max.