Rear brake pads wore out before fronts

[1980GS1000E]

I'm like Chef, I change out the rear pads three times as often as the fronts. Part of if is because there is only one disk back there, plus the rear caliper has two pistons and squeezes from both sides, the front calipers only have one piston each.

That has absolutely nothing to do with wear. The caliper is designed to slide allowing equal pressure on both pads.

Personally, I hardly ever use the rear brake on my FZ1. I have been riding 31 years and used to think the back brake was important but after having several close calls over the years I have found that unless traction is poor the front brake will stop the bike as fast as I can ever want. After all, the rear wheel has zero traction when it's in the air..

As for the GS, I will say that the traction just isn't there to lift the rear on that skinny front, but I hardly ever touch the rear anyway.