On Thursday, February 7, 2019 at 7:58:48 AM UTC-8, wrote:
On Saturday, January 26, 2019 at 3:59:53 PM UTC-8, wrote:
I was doing a hilly ride today. I came down out of the hills at 35 mph and stopped at a stop sign in the downtown Oakland Broadway. I came to a stop light and waited. A couple of other guys caught up with me. As I pull off on the green I accelerated up to perhaps 12 mph and that damned tubeless tire blew completely off the rim. It had about 90 psi at the beginning of the ride so it wasn't too high nor too low pressure.

I hit pretty hard but with so many clothes on because of the cold, I got relatively light injuries though it's a damn good thing that I had out-accelerated the cars and they saw it happen and had time to swerve out of the way as I landed almost in the middle of the street. The other two cyclist helped me up. After a couple of minutes I installed a tube and inflated it and rode home.

So I am now off of tubeless tires with actual proof that they aren't safe.

BTW, I fell on my side and slapped the helmet on the ground and it is broken.

OK - I got my new Maxxi Tubeless tires yesterday and the bead is substantially different from the Michelins I was using. You put the tubeless tire on and you have to be VERY careful to make sure that it is straight on the rim. You do this by flipping the wheel and making sure that it is perfectly centered on the rim. And then you can pump it up with a regular floor pump. You don't need anything special. Also, the tire will remain completely inflated even without the sealant in there because there is a soft rubber bead and a special bead to catch the hook on the rim.

Also they aren't particularly difficult to get on. Certainly they were easier to get onto the rim than the Michelins although not anywhere as easy as the one that came off the rim causing me to crash.

I happened to have 2 more ounces of Orange sealant so I put that in the front tire since I have total faith in the ability of that sealant to seal just about anything. But there is Finish Line that I put in the back since if I get a read flat it is far less likely to cause me to crash. The advantage of Finish Line is that it is a permanent sealant that doesn't need to be renewed every six months like the Orange and most of the others like Stan's etc.

So you have to be extremely careful to get the right tire for the right job. The Michelin 25 mm seems larger than 25 and the Maxxi's seem a little smaller than 25 mm but perhaps that is simply the way they fit on the rims.

I'll also have to look into Mavic who make tubeless tires now with the same manner of simply pumping them up with a standard floor pumps. Note: Finish Line sealant specifically says that you can use a CO2 cartridge to inflate them on the road because the stuff is good down to below freezing.


Read the directions. ProRaces are not tubeless ready. No Michelin road tire in the Power or Endurance road series is tubeless ready. That's why it blew off.

-- Jay Beattie.