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ninjunk · June 5th, 2015, 07:22 AM

One thing that i've noticed with vintage bikes, once the brake pad gets worn down signficantly, there is more exposed piston area (to be hit with corrosion) and more brake dust that is blowing around. This exacerbates the problem. Brake dust is the trifecta of corrosion: sticky, abrasive, and chemically reactive.

For me this is one of those 'do as i say, not as i do' kinda things because i'm super attentive to brakes and brake feel, but when i work on customers' bikes I expect them to be a bit more... how shall i say... oblivious. My own brakes i usually run them down to the metal and I don't rebuld them until something fails.

First of all, water sinks to the bottom of brake juice. That means any moisture that your MC picks up from sitting outside or what have you, ends up pooled in the bottom of your caliper rotting away. This means change your fluid more often if your bike sits outside or if you ride it in the rain. It costs exactly .45 cents to drain and refill your entire front brake system, I do it at least twice a year on a daily driver bike, if not more often. I'm racking up a lot of hard miles on the ninja and will probably at least check fluid condition in the next month or so. The ninja is small enough that you can pop a hose on your lower bleeder, turn the wrench, and pump the lever at the same time. If you know what you're doing you can bleed the entire system in about 10 minutes by just pinching the hose and letting the pressure push past your pinched fingers.

Back to the pads/pistons and 'outside' of the hydraulic system. You can clean the deposits or even rust pits off the pistons with #000 steel wool. They are pretty hard metal and won't scratch. You can also use a fine scotch brite pad, 800 grit sandpaper, etc, but both of those can scratch the metal as they use grit/abrasives which are harder than the steel.

If you get the brake dust deposits off and there are pits underneath, don't freak. You can re-install them with new seals and give it a shot. If they are weeping after that, they are done for, but hey at least ya tried. Just keep an eye on them. In several years of fixing some real basket case motos, i can only think of 1 or 2 times that the pistons were totally un-salvage-able. The combination of neglect and letting the pads wear down too far is the real killer. Most of the time even if they are pitted, it is only in the outer region outside of where the seal seals.

So yeah, to answer the question what to do between brake pad service:

1) Keep dust off the calipers, wheels, etc. (good rule for everything, really)
2) change your brake fluid at the end of every riding season or every 1000-2000 miles depending on how aggressive you are.
3) replace your pads before they are totally 100% gone and the pistons are hanging way out there.

June 5th, 2015, 07:22 AM	#23
ninjunk Lostcause enthusiast Name: Graham Location: Austin, TX Join Date: Jan 2015 Motorcycle(s): 2000 EX250F Posts: 178	One thing that i've noticed with vintage bikes, once the brake pad gets worn down signficantly, there is more exposed piston area (to be hit with corrosion) and more brake dust that is blowing around. This exacerbates the problem. Brake dust is the trifecta of corrosion: sticky, abrasive, and chemically reactive. For me this is one of those 'do as i say, not as i do' kinda things because i'm super attentive to brakes and brake feel, but when i work on customers' bikes I expect them to be a bit more... how shall i say... oblivious. My own brakes i usually run them down to the metal and I don't rebuld them until something fails. First of all, water sinks to the bottom of brake juice. That means any moisture that your MC picks up from sitting outside or what have you, ends up pooled in the bottom of your caliper rotting away. This means change your fluid more often if your bike sits outside or if you ride it in the rain. It costs exactly .45 cents to drain and refill your entire front brake system, I do it at least twice a year on a daily driver bike, if not more often. I'm racking up a lot of hard miles on the ninja and will probably at least check fluid condition in the next month or so. The ninja is small enough that you can pop a hose on your lower bleeder, turn the wrench, and pump the lever at the same time. If you know what you're doing you can bleed the entire system in about 10 minutes by just pinching the hose and letting the pressure push past your pinched fingers. Back to the pads/pistons and 'outside' of the hydraulic system. You can clean the deposits or even rust pits off the pistons with #000 steel wool. They are pretty hard metal and won't scratch. You can also use a fine scotch brite pad, 800 grit sandpaper, etc, but both of those can scratch the metal as they use grit/abrasives which are harder than the steel. If you get the brake dust deposits off and there are pits underneath, don't freak. You can re-install them with new seals and give it a shot. If they are weeping after that, they are done for, but hey at least ya tried. Just keep an eye on them. In several years of fixing some real basket case motos, i can only think of 1 or 2 times that the pistons were totally un-salvage-able. The combination of neglect and letting the pads wear down too far is the real killer. Most of the time even if they are pitted, it is only in the outer region outside of where the seal seals. So yeah, to answer the question what to do between brake pad service: 1) Keep dust off the calipers, wheels, etc. (good rule for everything, really) 2) change your brake fluid at the end of every riding season or every 1000-2000 miles depending on how aggressive you are. 3) replace your pads before they are totally 100% gone and the pistons are hanging way out there.