I posted this in another thread, here has been my experience with TUBELESS ready tires.
The following tubeless ready tires fit fine on my Enve 5.6 disc wheels:
- Specialized S-Works Turbo Road Tubeless (snug, had to work it on)
- Schwalbe Pro One (snug, had to work it on)
- Pirelli Cinturato Velo Rear (had to thumb on then it wouldn’t seal, took it to LBS and it took 4 attempts to get bead set)
These were very very difficult to get on despite using all tricks - heated tire in hot sun, lubricate rim, bead in center, pushing valve up to make more room, etc.
- Specialized Turbo RapidAir (really tight)
- Conti GP 5000 TL (really tight)
The following tubeless ready had at least one tire that slid on without any real effort:
- Hutchinson Sector 28
- Zipp Tangente RT-25
Both of those tires ended up burping and instantly flatting. The first one I brought the bike safely to a stop, the second one I went down and injured my thumb which took months to recover.
Moral of that story - when a tubeless tire slides on too easily think of it like the OJ trial - “if the tires don’t fit, you must acquit” (acquit = set free = throw in trash).
In other words, tire/rim interface can be a safety issue. Here is a graphic from a Mavic article highlighting the issue:
At least the GP5K TL isn’t a safety issue. When I got a flat and the one bacon didn’t seal the tire, it was about 90F and I was able to install a tube roadside. The next day I literally couldn’t get the tire on, despite using all the tricks. Maybe my thumb was too tired from the roadside repair. I dunno, but it killed my confidence in doing roadside repairs with this particular set of tires unless I started carrying a tire jack.
Enough people report the same install experience that I believe Continental erred on the side of caution with GP5K TL and slightly undersized these tires.
FWIW on the non-tubeless side of things, never had a problem installing the GP 4000 S II on these rims. It took a little thumbing and elbow grease (good fit), and when inflating they always made a reassuring “pop” noise when the bead snapped into the hooked rim. I probably installed at least 5 GP4K tires on these rims and they always were a good fit and always popped into place when inflating.