Disc brakes are here. We can debate why they're here and whether they should be here and whether we are all going to be slower for it -- actually, that we are going to be slower than an optimized rim braking equivalent is not a debate unless you are an industry insider or an imbecile -- but there is no argument that the rim-brake era is all but over.
Here's the thing about disc brakes -- they are fantastic, but for four reasons I don't foresee myself ever racing a triathlon on them unless wet weather is all but assured and the race is one I could drive to:
1) Disc brakes are slow. Or at least, they are slower than rim brakes. The smartest folks I know peg the aero difference between a P5-X as spec'd and a P5-X "de-disc'd" at 5-7 watts. This is even supported by people who are leading the disc brake charge, who will only concede such things privately. Assuming I can get a proper disc in the back and a Profile Design bottle cleanly in front of the head tube, there is likely not a faster bike for me on earth than the 2011 Cervelo P4 thanks to a combination of exceptionally low weight and best-in-class aerodynamic design. Peak aero...until now, when the industry is actually taking us backwards in both aero and weight.
2) Disc brakes are highly sensitive to configuration and prone to inexplicable brake rub, especially in inclement weather, even after the most diligent setup. This is not problem on a mountain bike, but if it happens to you in the middle of the race on the road, you might as well just stop. I cannot stand this rubbing thing on a TT bike, and while I never got a single hint of rub on the Andean, I've had routine misalignment on my Exploro and Strada. On the Exploro, I couldn't even get the thing to center without filing the paint on the stay so that the caliper could sit totally flush. Madness
3) Disc brakes are a pain to travel with to races. Rotors need to be TSA proofed (removed and wrapped in four layers of bubble wrap) and then invariably you lose those little pad spreaders and you have to go through the process of centering. Any time you have hydraulic hose it impacts your ability to cleanly disassemble the components of the bike for compact carry.
4) Flat changes would be 50% worse with disc brakes. Rear flat would be a 6 minute rather than 3.5 minute ordeal, which in my age group is the difference between losing five places and ten. And then afterwards of course you brake will be rubbing (back to point 2). Bonus points if you get chain grease on your hands and on the rotors and contaminate the system so your bike sounds like an aortic elephant every time you actuate it, which is every revolution because it is still rubbing.
So my solution is as follows: find my forever TT bike and ride it for the rest of my life in limited use cases (races) where it makes sense, and then keep it in the stable once I get an aero bike with rotor-based braking -- in my case, this will be the forthcoming 3TTT assuming Vroomen and SuperDave give us P4 and not Parlee geometry. I don't know which forever rim-braking bike is for me, but I've loaded up with some strong contenders and will eventually choose the rim-brake bike that performs best across all use cases -- then I'll sell the rest to someone who didn't get the memo that those brakes are over even though they are in many ways actually better.
How will you manage the transition from rim brakes to disc brakes and does the concept of a forever TT bike make sense to you? Have you found yours, or is that a hopeless task? Should the peformance minded or bourgeois among us just have two bikes forever? What about the proles -- can Premier offer a single Tactical that can be swapped between rim braking and disc braking / road and triathlon with quick disconnect hydraulics? Can Ventum offer a proprietary disc braking platform that is superior to both the incumbent and emerging systems in the market?
Here's the thing about disc brakes -- they are fantastic, but for four reasons I don't foresee myself ever racing a triathlon on them unless wet weather is all but assured and the race is one I could drive to:
1) Disc brakes are slow. Or at least, they are slower than rim brakes. The smartest folks I know peg the aero difference between a P5-X as spec'd and a P5-X "de-disc'd" at 5-7 watts. This is even supported by people who are leading the disc brake charge, who will only concede such things privately. Assuming I can get a proper disc in the back and a Profile Design bottle cleanly in front of the head tube, there is likely not a faster bike for me on earth than the 2011 Cervelo P4 thanks to a combination of exceptionally low weight and best-in-class aerodynamic design. Peak aero...until now, when the industry is actually taking us backwards in both aero and weight.
2) Disc brakes are highly sensitive to configuration and prone to inexplicable brake rub, especially in inclement weather, even after the most diligent setup. This is not problem on a mountain bike, but if it happens to you in the middle of the race on the road, you might as well just stop. I cannot stand this rubbing thing on a TT bike, and while I never got a single hint of rub on the Andean, I've had routine misalignment on my Exploro and Strada. On the Exploro, I couldn't even get the thing to center without filing the paint on the stay so that the caliper could sit totally flush. Madness
3) Disc brakes are a pain to travel with to races. Rotors need to be TSA proofed (removed and wrapped in four layers of bubble wrap) and then invariably you lose those little pad spreaders and you have to go through the process of centering. Any time you have hydraulic hose it impacts your ability to cleanly disassemble the components of the bike for compact carry.
4) Flat changes would be 50% worse with disc brakes. Rear flat would be a 6 minute rather than 3.5 minute ordeal, which in my age group is the difference between losing five places and ten. And then afterwards of course you brake will be rubbing (back to point 2). Bonus points if you get chain grease on your hands and on the rotors and contaminate the system so your bike sounds like an aortic elephant every time you actuate it, which is every revolution because it is still rubbing.
So my solution is as follows: find my forever TT bike and ride it for the rest of my life in limited use cases (races) where it makes sense, and then keep it in the stable once I get an aero bike with rotor-based braking -- in my case, this will be the forthcoming 3TTT assuming Vroomen and SuperDave give us P4 and not Parlee geometry. I don't know which forever rim-braking bike is for me, but I've loaded up with some strong contenders and will eventually choose the rim-brake bike that performs best across all use cases -- then I'll sell the rest to someone who didn't get the memo that those brakes are over even though they are in many ways actually better.
How will you manage the transition from rim brakes to disc brakes and does the concept of a forever TT bike make sense to you? Have you found yours, or is that a hopeless task? Should the peformance minded or bourgeois among us just have two bikes forever? What about the proles -- can Premier offer a single Tactical that can be swapped between rim braking and disc braking / road and triathlon with quick disconnect hydraulics? Can Ventum offer a proprietary disc braking platform that is superior to both the incumbent and emerging systems in the market?
