I do not enjoy replacing punctured tubes! Stupid thing is, EVERY one of my bikes runs a tubed tyre. Over the years I have looked at different solutions and apart from being expensive, you either have to send off you rim or it is "not recommended for road use".
I've seen a few YouTubes on DYI options and thought I'd give it a try. I've started on the URAL because I have 4 tyres. I tried two sealants, and settled on the SIKA 291. The tape, 3M Extreme Sealing Tape 4412N, seems to be what all the others use however I'm not convinced it's entirely necessary. I have put it on anyway because if anything becomes dislodged it's a safe guard. I initially used a right angle valve stem but have gone to an upright one because I believe the sealing system to be better (two rubber seals).
Thus far the tyres are holding pressure. If you do decide to do the same conversion, take your time and make sure the rim is super clean before starting anything. When I finished, I filled the tyre with 35PSI and rolled it through a tub of water to check for any air leaks.
I'm very pleased with how it all works and in future it I do have a puncture, I will be using our Puncture Repair Tool to fix it. NO MORE TUBES!!!
UPDATE 20/07/2020 - I thought it was all too easy. I developed a small leak in the rear tyre just 1-2psi per day. I subsequently removed the tyre pumped it to 40psi and put it through a water bath to try and locate the leak. Nothing!!! I'm off on a reece ride next weekend so I have chosen to put the tube back into the rear (in sidecar terms we call it a pusher) tyre. When I get time I will redo the tyre but try a different technic.
UPDATE 16/02/2021 - I am going to try the Tubliss system. Two of the 4 wheels I converted held up and never leaked. The two that didn't leak were the last two I converted. I would put the leaks down to "operator error". There is a new product on the market by Flex Seal called liquid rubber. I think this would be much better than sealing the individual spoke holes. I would spray on at least 3 layers allowing to dry between applications. I will try the liquid rubber on the spare and see how it goes.