Drum break lining thickness

[joseph2021]

Hello,

I am for the first time inspecting my rear drum brakes and would like to ask you about the lining, is it still think enough or should a i replace it? As in the pictures :

[FrankenMech]

A service manual is a good place to find answers to questions like this. They are available to download on site.

[snaker]

One thing I've noticed about small equipment drum brakes is that they don't tend to grow old gracefully.
The cables get dry and start binding
The pads wear down and get glazed over
The drum wears down and sometimes gets warped.
An often overlooked but key part is the drum actuator pin (the pin that goes from the outside levers to in-between the shoes)

Regular maintenance goes a long way
1. lube the cables
2. clean and lube the actuator pin (that means removing it to clean)
3. inspect, measure, deglaze the pads
4. same with the drum
5. clean all

The second photo shows the pin rotated at approximately 45 degrees of the cam from center
That's a fair amount, assuming the brake isn't being held on in the photo and the drum came off with that position
You can add more adjustment at the cables, but its likely to lose performance when the cam rotates past 45 degrees.
Drums usually (or used to) have maximum wear opening stamped into the cast for measurement
Problem there is a new drum might be spendy if even available.

So the best bet is to replace pads if the regular maint is ineffective.

[joseph2021]

Thanks you so much.

[GrumpyUnk]

If your rear brakes work and can be adjusted for proper freeplay at the hand lever, and the material on the shoes is as shown, you have a lot of miles left with your current brake lining. The brakes are not highly loaded as the mass being decelerated is not a lot in comparison to larger vehicles.
IOW, if the brakes work as they are, my personal opinion is they have a lot of life left. The thickness of the lining has not effect upon operation until they are worn too thin, and metal-to-metal contact is imminent. Even when worn that much, they will still work, though be very noisy.
If you get close to the end of the adjustment, replace the shoes. They are readily available and not expensive. The disk brakes will not indicate their wear except at the very end. Visual inspection for the friction material thickness is the only way to know their condition. If less than 1/8", I would replace the pads. Most scooters will need other maintenance before the brakes need replacement, but of course each one will have different usage and experiences.
tom