Agree with Mr B here , Discs and calipers should both be replaceable , unless you want to remake a rear axle assemble , whatever turns you on .

My idea of
http://forum.atomiczombie.com/showth...+outboard+quad

works well if you are well weight endowed I suggest a 3rd middle mount .

point Noted Mr B but then I am not a mechanical engineer ( I left in my first year ).

regards emma