Thanks for all the information. Why do you say not to use the spray foam on wire wheels?
I’m just interested. On my motorcycle and sidecar I have 4 inch inner tubes filled with a green gloop (can’t remember the make) as I can’t carry a spare and changing an inner tube is impossible by hand (I’ve tried), the sidewalls are too stiff. So genuinely interested on what options to deal with flats when out exploring, apart from using the spare.
