Originally Posted by Bob Dopolina

Black Chili can't be bonded to the same chemicals used in the tires using silica. The compounds that make coloured tread work fine with the silica compounds but are incompatible with the black chili compounds. That's why all the black chili tires are only black.

I do know that dual compound tires are a tally hard to make because the compound flex at different rates during deflection and this leads to a breaking of the bonds between the two compounds at a molecular level. This was an issue with the first Vittoria dual compound tires where the grippy strips on the side would separate from the harder compound used for the center do the tread.

I speak from personal experience here as this problem put me into a guard rail at the end of a crit.

So, given this information I would assume that what Continental is claiming seems at least within the realm of possibility.