Bicycle Mechanics - rim destroyed by innertube explosion

I recently purchase bontrager hard case tires and new tubes for my trek 7000 hardtail mtb. I was careful to check the bead of the tires as i mounted them and inflated gradually to make sure they were sealed properly. They are rated up to 85 psi which i have been keeping them up to for about 2 weeks since i got them. They have around 100 miles on them asphalt only. Today i took a 20 mile ride at moderate speeds took about 2 hours. I stopped at a local river and after about a half hour i heard a LOUD explosion. It sounded like a gun shot. My inner tube exploded with such force that it blew a nine inch section of the side of my rim off! The tire was perfectly fine. The tube is 26x1.25-1.75 and the tire is 26x1.5. Could the warm weather of about 70 degrees had anything to do with it? It was the warmest day ive been out riding so far in Chicago. The cut is right at the seam starting at the valve and a quarter inch piece is missing that is about 9 inches long the same length as the rim that was blown off. How could this have happened?? Was it a pinched tube?? I can't believe it could have exploded with that much force? Help?? thanks.

i guess in theory the warm weather could have raised the psi...but even if its rated at 85 you can go up behond that. so i dont think it was the weather. where is the damage on the rim? around the weld?

deffinately sucks. how old is the bike and esseintially the rim? you might be able to go through some sort of warranty issue if its not too old depending on brand

if the bike and rim are arent damaged, from a fall since thast what would have happend if you had a blow out moving, im sure you can 'argue' you didnt 'damage' the bike 'using' it.

even if the tyre was not seated right, the tube would have just poked out and blown up the tube and or tyre...which ive done my share of times.

put up a picture of the damage, maybe someone can judge what caused it better


good to hear you didnt have a blow out while riding :\

Definitely sounds like rim failure is the reason you're tire blew.

Definitely sounds like rim failure is the reason you're tire blew.
bingo. The rim failed and the sharp edges ripped the tube in the catastrophe.

Definitely a rim failure that caused the problem.

It sounded like a gun shot.

Maybe some jackass kid shot your bike while you were standing there. But probably not.

heres some pics if it works this is what the rim looked like after. i wasnt riding it when it happened, thanks for the comments. Should i contact bontrager about it or trek?? what should i tell them happened ?? thanks! http://hotimg2.fotki.com/b/65_141/157_78/bike.jpg
the damage goes from the seam where the spokes are in the center to the side of the rim. the spokes are all still intact with the center.

http://hotimg6.fotki.com/a/65_141/157_78/splitrim-th.jpg (http://hotimg6.fotki.com/p/a/65_141/157_78/splitrim.jpg)

http://hotimg1.fotki.com/a/65_141/157_78/rim1-th.jpg (http://hotimg1.fotki.com/p/a/65_141/157_78/rim1.jpg)
http://hotimg5.fotki.com/b/65_141/157_78/rimnpiece-th.jpg (http://hotimg5.fotki.com/p/b/65_141/157_78/rimnpiece.jpg)
http://hotimg2.fotki.com/b/65_141/157_78/rimpiece2-th.jpg (http://hotimg2.fotki.com/p/b/65_141/157_78/rimpiece2.jpg)
http://www.bikeforums.net/%5BURL=http://hotimg1.fotki.com/p/a/65_141/157_78/rim1.jpg%5D%20%5BIMG%5Dhttp://hotimg1.fotki.com/a/65_141/157_78/rim1-th.jpg%5B/IMG%5D%5B/URL%5D

Rim failure. Defective if new...Abused if older. Sidewalls of the rim can get thin as they are old and worn by repeated breaking. If you dinged the rim Aluminum can propagate stress damage. Talk to your trusted mechanic.