Note: this is article 3 of 3 today
[ a minions experience with airless bike tubes ]
Just got off the phone with my bike shop, confirming they were "nu-tek" or "nu-teck" he couldn't remember how to spell it, and I've found both online.
I had them order and put them on. All together it was about 200$ I had them do it due to the idea that they are insanely hard to mount for the inexperienced.
The installer confirmed the hours of difficulty with mounting. Also they had not had anyone want something like that for at least 10 years, so they had no real experience either.
I got out their door and tried to ride the bike in the parking lot. It was highly resistive to pedaling and bumpy. I went right back in the shop. They said that that's just how they work. I asked them to drive it and they said they would while I went to lunch. When I returned they said they couldn't go more than a few hundred feet. Their call to the manufacturer resulted in a reply that basically said they were defective from the factory.
The tires were not one circular piece of foam, rather several.. I'd guess 10.. curved foam pieces, each similar in shape to a banana. These pieces were fitted and secured into what looked like a normal bike tire. The bumpy feel was, in my opinion, each piece compressing in it's center and not compressing on their ends.
The bike shop agreed to remove and refund my costs. I ended up with normal tires with tubes. And have had no problems since. It rides and pedals beautifully now
This was on a 1986 Dahon stowaway fold-a-bike 5 speed with 20 x 1.75 tires.