On 11/19/2015 9:31 PM, Phil W Lee wrote:
Doug Landau considered Wed, 18 Nov 2015
14:36:45 -0800 (PST) the perfect time to write:


Disks are a bad idea on street bikes because they have low rolling resistance

Disk brakes have rolling resistance?

In use, yes.
It's kinda the point

There's no reason that a properly aligned and adjusted disk caliper
should drag any more than a properly aligned and adjusted rim caliper
when released.

I've never owned a disk brake bike, but I've ridden several that
belonged to others. Some definitely made scraping sounds with the brake
off. One tourist who had ridden 60 miles that day to get to my house
assured me that the scraping was "normal."

I can't say how much drag it imposed; my ride was a short one, testing
an unrelated repair I made for him. But I know the scraping would have
driven me nuts.


--
- Frank Krygowski