I've been reading your posts - you ride like us. Our tandem takes some serious abuse as well. We've got a custom ATC Racing fork (5" travel) with the 20mm thru-axle. This gives me the confidence to push the bike hard through the rough stuff. When I spec'd the frame, I had them make the Ti rotors too. Looked cool, but as I stated, not the best material for brake rotors. An expensive lesson.