Cycling in Melbourne Australia
Not sure if any one else had encountered this problem but this is the second time something like this has happened to me. I mount my bikes on a bike rack which fits to the towball, whilst driving on the highway in SA last week i heard a loud bang and sure enough when i inspected the bikes one of the tyres had exploded. I'm not just talking about the tube but the tyre actually shredded, even had to replace the rim tape. Not what i wanted the day before riding in the Bupa challenge at the tour down under.
The time it happened before was also similar circumstances. Has this ever happened to any one?? i figured i'd put it down to traveling at high speed in hot temperature and a random stone popping up and hitting the tyre, causing it to explode. Any suggestions?
I had a run of this happening. Never on a car, once inside my office though... scared the crap out of all of us!
Also it once happened while I was riding and blew the tyre off the rim!
What was happening in my case was the rim tape had slipped and exposed the hole in the rim that the spoke goes through. So as the wheel heated up and things expanded, the metal of the rim rubbed on the tube and popped it.
So, replacing the rim tape sorted things out for me. I see you've already done that, have you had it happen again since replacing the tape ? You'll also want to make sure the tape is on nice and tightly and the rim surface is clean before doing it so it won't move around and happen again.
I wouldn't have thought that a stone flicking up would cause it though.
Silly question but is the exhaust pipe on on the blown tyre side. Or maybe the heat from the engine could be the culprit. Just a thought.
It looks like you're right on the money there Jack. I've just done some google -ing and yeah, seems to be that the exhaust pipe can really heat up and melt the tyre. I don't know what to do, certainly don't want this to happen again. So i guess i'll just have to travel with the bikes on the racks with out their tyres??? major pain in the a*s.
Simple case of high pressure tyre exposed to the sun - I've stood near triathlon bike parking areas on several occasions and heard multiple tyre explosions when the sun came up. People inflate them to the maximum pressure when cool, then when the sun hits the black tyre they heat, the pressure goes up and bang! I've had it happen to a tyre in the back of a car too. Try inflating them just a little less, even 5-10 psi will make a difference; the high pressure and subsequent increase in pressure will find any fault in the tube/tyre. Alternatively, inflate just before you start the ride & the air on them will keep them cooler; If you think it is the exhaust, then change your rack, but I've heard this plenty of times off the rack.
Yes heat of any kind can do this, and for that reason it is always best, if you're leaving your bike inside a car during summer, as I do, to drop the tyre pressures a little. It doesn't take much to pump them up again. But in a hot car, where I believe temperatures can reach 60 degrees, you're running risks if you leave your bike in there with fully inflated tyres.
I have wondered about something else. I did the Alpine Challenge last week with full tyre pressure, 120lb. it never occurred to me till later but temperatures on the day, gong up Buffalo, exceeded 40 degrees, and the bitumen was melting on the road. The heat from both the day and the bitumen must have put the tyre pressure through the roof. I'm surprised I didn't see more blowouts on the day.
Yep, it could let go, but you are constantly pushing the bead back into the rim as the wheel rotates, so it would have to be pretty bad; of course, the consequences would be pretty bad too!
As well as boosting the pressure in the tyre, the relative pressure would increase too as the outside pressure drops with altitude. Scary thought.