Drum brakes

Yes, plenty use a spring mechanism in the caliper to brake with the disk

1. More efficient than discs
2. Don't require servos
3. Modern pads can handle more than one panic stop

Disc brakes are like rear wings and lap timers
>pointless on commuter cars

>1. More efficient than discs

Drums like the bike part in your photo are terrible stoppers (I've been a motorcycle mechanic since that shit was standard, 4LS style shown is best of breed which doesn't say much) which is why they are gone from serious motorcycles and cars. That one would look nice on my Norton Commando though. :)

Drum feel a shit because drums self-energize. Servos are trivially cheap.

You may be too young (and I'm barely old enough) to remember brake shops being common at the bottom of steep mountain grades, but those went away with modern disc brakes which actually shed heat.

Rear brakes don't matter on the street and drums on cars and trucks permit cheap, reliable parking brakes.

Street ain't racing.

Aren't drums incompatible with ABS?

No

>are terrible stoppers
Wrong, they are excellent stoppers, they're terrible at dealing with heat.

>which is why they are gone from serious motorcycles and cars.
They're gone because they can't deal with heat and moisture. They can and will stop on a dime if they are cold though.

t.daily a car with 4 wheel drums.

>4 drums
What kind of shitbox do you drive? My 1984 chevette has front disk brakes.

It's a 61 Corvair

mud, GM switched alot of their Silverado and Sierra here in north Canada back to rear drum brakes because rear disc brakes were clogging with mud in the oilfields constantly. having had worked on oilfield trucks for nearly a decade i can confirm mud gets everywhere

no, many older drum brake vehicles especially GM and Toyota had rear drum ABS. Chevy Cavalier and Pontiac GrandAm had rear drum ABS in the early 90s and Toyota Sienna used it in the late 90s

i was a automotive tech for a decade, he is right that drum brakes stop better than disc brakes. plain as day, its just that in sports cars and such they would overheat to hell when you rip and race the thing and you would get horrible brake fade

Drums give the best braking force relative to the control input required. This is why they don't need servos, or hydraulics. This means you can have a powerful, reliable braking system with less points of failure compared to a disc system.

This is about the heaviest vehicle that you will find disc brakes on. Because truck rims are a standard size, you can't make the discs any larger to increase your braking torque. So you have to use incredibly high clamping forces which trash pads and rotors in no time, plus it requires such a huge energy sucking servo that it's just not worth it. Drum brakes are more powerful which is why they're still used on 2017 model trucks.

As for passenger cars, if the brakes can handle like two panic stops, there isn't much more call for fade resistance beyond that. So drums are still relevant, they're just poo-pooed by the average joe buyer.