Originally Posted by
Jon_g2
Thanks for the information.
And yes, I never meant to sound like these rotors I have don't work or. I do believe in trying stuff out before replacing but I did mention that if the RT70s weren't good enough for steep descends I'd rather not have to find that out during a ride. I believe my braking technique is pretty good too. On top of that, it's my first brand new bike and I don't plan on buying another road bike for many years to come so I want to upgrade it where needed.
For reference I’ve ridden stock 105 brakes down twisty 20%+ descents many times on my Giant Defy and it has the small 140 mm rotors front and rear. Not a hint of brake fade or lack of power. I’m an 80 kg rider with reasonable technique. I’m a confident descender, but fairly conservative. I’ve done some big climbing/descending days (4000 m) on this bike and never even felt the need to fit a larger 160 mm front rotor. The standard pads are quiet too and have good wear life.