WHEN DID I LAST FIX MY BIKE?
MAY 16, 2023
Short answer: Today. LOL.
Long answer: My bike has been parked for a while and the front brake locked up for some reason. There was so much pressure that it caused the pistons to push out and squeeze the brake pads together...on their own. Ghost rider?
My first thought was to release some brake fluid from the bleeder and maybe the brakes would release on their own. No go. So I decided to remove the caliper from the rotor and see if I could pry them apart. No go. They were not going anywhere. No wrench, screwdriver or hammer could open these safety jaws. So my next plan of action? SEEK AND DESTROY the brake pads for just a little gap to start prying. Now you may be wondering, that's impossible and such a waste of brake pads! You may be right if they were brand new. But these were in such bad condition that they came apart like extra burnt chocolate chip cookies off a thrift store baking pan. Brake pad chips, anyone?
I got some play after destroying the brake pads, but it wasn't enough.
So I ended up having some hangly dangly brake pad holders? But I couldn't remove them because the plug pin was so grinded from the previous owner that...I needed help. I called the cavalry. I asked a mechanic to do a housecall to remove this plug. Luckily the mechanic lives next door. He came and went and like the wind. No, seriously, he arrived early in the morning and left before I woke up. Bless his grease monkey heart.
I pumped my hand brake and saw only one piston was functioning. Something was making it stuck. There was some black rubber jammed, so I started cutting that off with a box cutter against my piston. I realized I needed to remove both pistons and do a thorough cleaning. This took quite a while trying to get both pistons out at the same time as only one was functional, and if you remove one completely, you lose the pressure you need in order to get the other one out. YouTube University says an air compressor can help remove the pistons, but I don't carry that in my bags on the road. Little did I know, this little project is called "Rebuilding Your Brake Calipers".
So that's my current project. I'm moving slow now, so I can finally work on my bike myself. Usually when I move fast, I just pay a shop to fix problems or do maintenance, but I feel handicapped from knowledge when I do this. I don't like it, but sometimes time is of the essence to escape the rain or avoid Visa issues.
So why did my brakes lock up? Probably corrosion. The one piston wasn't working properly because the dust seal got caught, bent, warped, and caused corrosion. There is so much gunk stuck where the seals are. Parts of the dust seal wore off, got caught and prevented the piston from freely being able to move. I learned this just by taking it apart.
Rebuilding a brake caliper is not as daunting as you think. Honestly it's just a lot of cleaning and getting the gunk out. If I can do it, anyone can do it.
It helps to keep the gunk down if the brake fluid is bled on a yearly or 2 year basis at the most. Brake fluid absorbs water out of the atmosphere, the entrapped water then wreaks havoc on the caliper innards with corrosion building up at the interfaces of the seals typically. That crusty white or greenish powder-like yuck.
Lucky you can find caliper piston and seal kits still for the bike. Maybe in Europe those parts are more readily available for the NX250? Not quite as common a bike here in the US, sadly.
People look at me strange when I say I flush my brake fluid every year or two and replace pad pins when I see even…