Originally Posted by
rpenmanparker
I know of no tendency of the Conti GP4000S IIs to blow out. The fit of the foldable bead is very tight and secure. The only examples of blowouts that I know of personally are from tubes trapped under the bead during installation. They are very resistant to side wall cuts as well. I have been riding several sets of the Contis for years with no issues such as you are asking about.
That seems to be the common feeling about them, but check this out:
http://www.amazon.com/Continental-Gr.../dp/B00PUE4NKY (9% 1 star, interesting photos of sidewall blowouts)
These type of reviews are found all over the web on sites that sell the GP4000s II's. It's more so than other tires, but obviously one can argue that at this price point, people are more willing to get online and write a bad review about issues than a $25 tire.
What's a good PSI to run the 25s at?