I Want the Fastest Balloon Tires!

[DougC]

One thing to remember is that fat tires put way more stress on the edges of a rim than thin tires would at the same pressure. The limiting factor in how high you can safely inflate a bicycle tire is not the tire's strength but the rim's strength.

In manufacturer testing, most tires burst somewhere between ~300 PSI (for cheaper/fatter tires) and ~450 PSI (for better/narrower tires). No normal bicycle rim could take that much pressure tho'.

One bike I have has Mavic X325 Disk rims on it, which are MTB / downhill (heavy-duty) rims.
A decal on the rims says that the maximum pressure for 2.1" wide tires is 55 PSI, and for 3" tires the maximum pressure is only 32 PSI.....

 

[Bicycle808]

One thing to remember is that fat tires put way more stress on the edges of a rim than thin tires would at the same pressure. The limiting factor in how high you can safely inflate a bicycle tire is not the tire's strength but the rim's strength.

In manufacturer testing, most tires burst somewhere between ~300 PSI (for cheaper/fatter tires) and ~450 PSI (for better/narrower tires). No normal bicycle rim could take that much pressure tho'.

One bike I have has Mavic X325 Disk rims on it, which are MTB / downhill (heavy-duty) rims.
A decal on the rims says that the maximum pressure for 2.1" wide tires is 55 PSI, and for 3" tires the maximum pressure is only 32 PSI.....

I run 60psi in my franks on Sun MTX33 rims....hasn't killed 'em yet. Been running that set up frequently for at least 18 months....**EDIT** Not trying to present an argument; Doug makes an interesting point here. I was just adding my experiences as a data-point for anyone interested in high-psi fatties.