chrisvu05

So what would make a brand new tire explode off the rim? I got back from a 50 mile group ride this afternoon and went into the shop with the owner and leaned my bike against a wall....we all walked to the back of the shop to change and get water...there was a loud explosion (similar to a gunshot) and we all went running to the front of the shop to see what happened....we figured one of the bike fell through the plate glass window in the front...we looked around with no luck and then I looked at my bike and noticed that the front wheel was completely flat and had exploded off of the rim. This is a brand new pair of Vittoria Rubino Pros that were put on yesterday....they were pumped to 110 psi which is well below the limit of 120 psi. Any advice is appreciated as I'm now afraid to ride these wheels....had this happened on one of our 40+mph decents today I most likely would've been in the hospital right now.

Snicklefritz

That is strange! This has happened to people in my club but the one or two times was on a descent on a very hot day where they were breaking a lot on the downhill. I think the rims got really hot and that heated the tube of amd BAM!!!

How hot was it out today? If you pumped it to 110 psi I wouldn't think it would be an issue though. On hot days out here I generally inflate to 100 or 110, well below the limit of 125 psi.

chrisvu05

it was in the high 70s today but lots of high speed decents that could've heated the rim....the crazy thing though is that I had been off the bike for atleast 5 minutes before it blew

Markedoc

Bad bead

chrisvu05

does this mean the tire is bad? or that it just wasn't seated properly?

ViperZ

How hard were the Rubinos to mount onto your rims?

I remember back in the 80's I had a set of Michelins that mounted very easy on the rim, they practically fell onto the rim.

With those tires, I also experienced the tire blow off twice while ridding. Needless to say I pitched the tires after that. In my case I think the tires were too loose for my rims, allowing the tire to blow off easily. I'm not saying this is your problem, just relaying my experience with it.

Either that or you could have had a pinched tube where the tube was trapped between the rim hook and tire bead.

worker4youth

if you installed it yesterday, it was probably a manufacturer's defect. Call them up and ask them to replace it or refund.

chrisvu05

I didn't put the tires on the rim....so i'm not sure how hard they were to place...my mechanic has taken a great interest in my bike and has done all work necessary free of charge...he even gave me the wheels at cost....

krazyderek

This "explosion" actually did happen to me while pulling along at 40kph on day, ironically on a set of vittoria's, the evo corsa cx. It was basically just a gun shot sound, then i almost lost controll of my bike. I chalked it up to improper installation/old tube, but who know's the tub was completely shreaded by the time i came to a stop. My rim was also bent up a bit, and some nasty scratch's on the tire's sidewalls.

nova

Id say same as others probably a bab tube. Maybe part of the tube was pinched in the bead 101 possible causes realy. Worst thing i ever had happen was on a 24 inch bmx bike with high resure road tires (think wide flat road surfave good on road or packed dirt r ramp jumping wich was case with me) 100 psi tires. I was going along at a fairly decent clip no comp of corse but guessing around 17 to 20 down hill and had the rear tire expload with enough force to make me do a rat hop. It my case it turned out that my breaks were alittle to tight and off center a bit so one was rubbing the side of the rim and heated it up. If i had to guess i would say that the tire blew out at around 120 psi. !20 psi on such a tire is alot more explosive force than a road bike tire at the same presure (more volume).

Was quite frightening to say the least.

Retro Grouch 

BINGO! It's actually semi-common.

ViperZ

So how hard was it to dismount and mount when you or your mechanic repaired the Blow-off?

If it was a loose fit it would be obvious to him, chances are it was a pinched tube as I mention earlier, if not a loose fitting tire.

chrisvu05

we didn't repair the blow off yet...the shop was closed...i'm taking it in tomorrow morning....i'll ask about it

KevinF

As others have said, all kinds of things can cause this. The tube was probably squished by the tire bead. Perhaps there's something sharp sticking up from the rim? i.e., if the rim tape isn't seated properly then the tube could have blown on a protruding spoke nipple, or a metalalic splinter, etc. I'd give the rim a real thorough look for anything even remotely sharp and if you don't find anything, then you can credit it to either a defective tube or a bad tire mount.

Al1943

9 times out of 10, bad tube installation, caught between tire and rim, eventually squeezes out past bead and KERPOW!