Tire Blowout Insight

[Eric7]

Not directly related to Rad products.

I have a Burley bicycle trailer (I think a famous brand) with plastic wheels that takes 20 inch tires.  I have been running 30 psi forever and never had any problems.  The other day, I noticed that the tire states the maximum PSI is 45 pounds so I pumped it up to 45 pounds and the tires promptly blew out after sitting fine in my driveway for about 10 minutes undisturbed after inflation. 

I put in new tubes and tried again and the same thing happened - a blowout after sitting 10 minutes on the driveway while I was fixing a bike.

My conclusion is that regardless of what the tire says, some rims are not made to handle all that pressure.  I think the plastic rim is too small - making it easy to change the tires but easy to blowout too.  The rim does not appear to be damaged. My conclusion is that you have to keep the instruction manual and follow it.  The recommended inflation is 30-35 PSI.  At 45 PSI (Max Sidewall Printed Pressure) there is a blowout.  Seems to me that the margin of error is low.

Maybe it applies to bicycles and bikes too.

[john in Idaho]

It may be that the tire was not seating right in the rim.  I have had trouble getting lawn cart tires seated in the rims.  You have to inflate a bit and then go around and make sure the bead seats in the rim.  It is very subtle.

[Eric7]

It may be that the tire was not seating right in the rim.  I have had trouble getting lawn cart tires seated in the rims.  You have to inflate a bit and then go around and make sure the bead seats in the rim.  It is very subtle.

Thank you for the tip.  I'll take a look. 

[tacomanatx]

Take a cotton ball and rub it on the inside of the tire... I bet you have something poking the tube.  At a lower PSI the tube may have some flexibility but at the higher PSI it will puncture.

How did I learn this- while commuting years ago on my road bike.
*Pumped up tires in the AM to 100 PSI road 13 miles to work.
*On the way home its now 95-102F and at the 8 mile mark time and time again the tire punctured.
*Found one of the kevlar threads loose on the inside and covered it with a tube patch
*Ran another 600 miles on that tire.

[Tree]

Take a cotton ball and rub it on the inside of the tire... I bet you have something poking the tube.  At a lower PSI the tube may have some flexibility but at the higher PSI it will puncture.

How did I learn this- while commuting years ago on my road bike.
*Pumped up tires in the AM to 100 PSI road 13 miles to work.
*On the way home its now 95-102F and at the 8 mile mark time and time again the tire punctured.
*Found one of the kevlar threads loose on the inside and covered it with a tube patch
*Ran another 600 miles on that tire.

haven't heard of the cotton ball trick, but definitely this. i had a tiny goat head thorn poking my tube, causing two flats.

i didn't find it. a tech at REI didn't find it. a SECOND tech at REI did.