Why A Bike Fitter Still Chooses To Buy Rim Brake Bikes

[carlucci1106]

Originally Posted by krooj

Rim brakes have way better modulation and give you the ability to confidently scrub speed, where discs aren't treating a structural component as a wear item. Pros/cons.

This is subtle, but I like what you did here. With a carbon rim, this is a major $$ consumer, if you have to replace rims.

With an aluminum rim, you're likely going to get 2 to 3 rotors-worth of use before needing replaced, and it's about the same cost (when factoring in brake pads with each rotor, as you should do). But excellent point on the "for" side of disc brakes. Show my work for this:

Ultegra Rotor 59.99*3= 179.97
L02/LO3 Pads 24.99*3= 74.97
= $254.94

DT Swiss RR 411 Rim= $128
28 DT 14/15g spokes @$2.99= let's say 83.72
= 211.72

Let's assume you've replaced the rim pads in there twice, which you may/may not have done, and it's about even. Replacement rim pad inserts are as cheap as $9-13 with a little Google shopping. As much as $25 for OEM.

The labor for replacing the rotors and pads three times should be about $90, as likely the caliper would need to be adjusted. This is assuming $10/per itemized labor/job. And this factors out brake bleeds which are always needed on SRAM, almost always needed on Shimano. @$20-30/wheel, so you could also factor this in, if you think 2 rotors would last what a rim would. Truing rotors/rims is probably a wash, too. Minor true on a rotor @$10, minor true on a wheel $15-20, but needed less often. Rotors warp pretty easily.

The labor for rebuilding wheel should not exceed this at most shops. $60-80

I should have said in my post about the causal nature of discs probably started when carbon rim brakes were not performing well in the wet, tires blowing off rims, etc.

But the whole bike was overhauled from an engineering standpoint as a result of this. Was carbon rims enough to warrant a wholesale change across the board, or should it have been restricted to top-level race bikes?

I think most rational consumers know the answer to that. A $400-500 hardtail or hybrid is going to have brake maintenance at some point that for most people is going to "total" the bike (replace rotors/calipers, and maybe brake levers/shifters too).