Out for a ride last night and went off a c.5 foot drop with the front wheel landing on what I suspect was an off camber bit of trail. As a result the front tyre came off the rim completely on landing. Not just a burp, fully off. I was running c. 26 psi so nothing silly and it was a Der Baron Projekt Apex Protection tyre which has only been used for c.10 rides with a DT XM481 rim so not a fudged tubeless set up. Is the tyre likely to be weaker/more susceptible to doing it again as a result? I suspect it’s absolutely fine but just wanted to check as I really don’t want it to blow off at pace and get tangled in the forks. I’d rather buy a new tyre.

When you put the tyre back on, and push the last bit of tyre-bead over the rim edge, does it sort of ‘snap’ into place, or does it just sort of roll over without any resistance ? If it’s the latter, I’d say replace the tyre, as in theory, the bead (wire or kevlar) could stretch, although it would be quite unsual.

As you probably know, if a tyre is a bit loose on the rim, it’s possible to pack out a rim with tape or a rubber rim strip. This is usually only necessary to make it possible to inflate and ‘seat’ the tyre bead into the rim hooks. #

Assuming you’ve been able to install and inflate the tyres OK, it does sound very odd that it could come right off the rim. I’m running tubeless on 3 of my bikes and I need tyre levers to get the tyre off…..

Have you tried putting the tyre back on?

I had a similar thing with a Nobby Nic and when I remounted the tyre it made the decision for me as it had a ‘buckle’ in it where the structure of the sidewall must have been donald ducked.

Not yet. Walk home last night wheeling the bike on its back wheel meant it got shoved in the shed to be dealt with tonight.

They were reasonably tight to get on the rim albeit easily doable with thumbs.

Will check it spins straight when back on.

The conti tyres haven’t been the greatest to seal ie they blow up fine but lose pressure over a week or so. However I’d put that down to Stans as I was having the same problem with a Specialized Grid tyre I’d put on the other bike using the same sealant having had no such problems with that wheel/tyre combo when using café latex.