Trav
Pad X (Pad Reach) is a number that needs to be at least 400mm, prolly more. Double check that. Just as an example…if the tip of your Sitero measures 530 to the center of your pad, and the tip of your Sitero is set back 60 your Pad X is very likely 470.
And if you don’t have the Pad Stack now I can help you find it if you’re near your existing bike. Get back to me here.
Ian