Hookless rims: Not ready for prime time?

Sure no proof, but if you cant hit a rock when you’re riding your bike without the tyre blowing off there remains a safety problem. Where is the proof of damage to the rim? Hitting a rock is not enough of an explanation.

 

What size rock and at what speed?  Agree that seeing a pic of the damaged rim would be good. 

 

I've hit all sorts of potholes on my gravel bike though, but one of them I was going faster and pinch-flatted my tubeless tire and had to put a tube in.  Gladly I didn't damage my rim. 

Exactly, hitting potholes and rocks while riding a bike is totally normal. Sounds like you hit that pothole pretty hard ...but your whole tyre didn’t blow off?  If a tyre company is using hitting a rock as an excuse for their tyre blowing off a rim, it doesn’t say much for the tyre!

It was a pretty hard hit.   But it was on a dirt road. If it had been on pavement, I doubt the rim would have survived. 

Yes, hitting small rocks is common.  But, if the rock is say baseball sized and hit at high speed?  That would easily bottom out the tire and impact the rim with a sharp edge. 

Their explanation was that the rim failed.  Yes, needs verification but failing the rim bead would potentially cause most any clincher to come off.  

This article is very clear on how to use hookless rims safely:   https://www.renehersecycles.com/uae-tour-and-tubeless-what-is-safe/

Zipp releases photos of the rim.  (front page of Cyclingnews.com)

Has anyone seen an image of the actual rim failure?  …The most likely cause seems to be a 28mm tyre on a 25mm internal width hookless rim, with the green foam insert, possibly at too high a pressure, all adds up to the reason hitting a rock blew the tyre off the rim. I’m no wheel/tyre expert, but I follow the guidelines for hookless. …I run hookless rims 25mm internal on my gravel bike, but my tyres are always 40mm+ wide, arguably making the tyre more secure on the rim. Max pressure I use for these tyres is 50psi (max limit for hookless is 72psi, but some tyres say 60psi. I never go over 60psi). I’ve never had a problem. I won’t use tyre inserts either. I reckon they get in the way of the tyre / rim functioning properly. It seems to me that the reduced air volume and increased stress on the tyre to contain the insert is potentially problematic on any rim. NB:  I also use wheels with 25mm internal rims on my road bike, but they are hooked rims with 32mm tyres and never over 60psi.

Has anyone seen an image of the actual rim failure?  …The most likely cause seems to be a 28mm tyre on a 25mm internal width hookless rim, with the green foam insert, possibly at too high a pressure, all adds up to the reason hitting a rock blew the tyre off the rim. I’m no wheel/tyre expert, but I follow the guidelines for hookless. …I run hookless rims 25mm internal on my gravel bike, but my tyres are always 40mm+ wide, arguably making the tyre more secure on the rim. Max pressure I use for these tyres is 50psi (max limit for hookless is 72psi, but some tyres say 60psi. I never go over 60psi). I’ve never had a problem. I won’t use tyre inserts either. I reckon they get in the way of the tyre / rim functioning properly. It seems to me that the reduced air volume and increased stress on the tyre to contain the insert is potentially problematic on any rim. NB:  I also use wheels with 25mm internal rims on my road bike, but they are hooked rims with 32mm tyres and never over 60psi.

It seems to me roadies are very wary of new tech.   It seemed like people were just waiting for something to happen to blame hookless rims.  People who had zero facts had already made up their minds about what happened.  This reminds me a lot of all the fear mongering over disc brakes and how everyone said racers will get cut up by the discs.