Canti brakes are simpler, mechanical. They weigh less. Replacing cables and adjusting them is easy.
Disks (assuming they are hydraulic and yes there are mechanical disks but there is no point to them other than cost) offer easier brake lever pull feel. They are like having power brakes on the car, you don't have to squeeze the levers as hard. Hand fatigue is less when you have to brake a lot, like on long downhills when you are trying to regulate speed. Yes the disks can get hot, and it is better to put the front QR on the side opposite the disk to minimize the chance your hand will touch the disk if you are removing the wheel. It is more involved to center the brakes (I use a feeler gauge to 'gap' them and it makes it easier.) It is NOT hard to bleed the brakes; I have done it, but it is not so simple as replacing a wire and you should really have a bike stand to hold it steady or you will have brake fluid mess. (trust me on that one
)
When I go from my MTB to my road bike, I am reminded of how different they feel. The disks can really stop faster with much less hand strength.
Oh, one other difference comes to mind. If you knock the rim out of true, you don't have to worry about the brakes rubbing with disk brakes (unless you bent the rotors).
Tzvia- rollin' slow...
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