Thursday, April 3

Spring Cleaning: Brakes and Gears (4/5)

My bike has started to sound like a hamster wheel when I pedal. It's kind of embarrassing. Also the shifting is off--when I pedal real hard, it clicks gears by itself, or sometimes when I shift it gets really chunky, but doesn't shift. Also, the rear brakes totally suck. They are either too loose, or they don't release the wheel when I let go of the levers.

The cause of all these problems is excess of dirt and lack of lubrication. Also there's probably some slack in my shifter and brake cables, and the dérailleurs need to be re-calibrated. Today, I'm going to do a minor overhaul and major cleaning of my brake calipers and dérailleurs.

Brake Caliper Overhaul

Let's start with the brakes. I didn't really do too well at cleaning the brake area yesterday--the sponge can't really get in there. I'm going to remove the whole brake, clean the heck out of it, degrease it, regrease it, and put it back together. I have caliper brakes (the brake unit connects to the frame at one point, as a singular unit) but if you have cantilever brakes (each side of the brake connects to the frame separately) then you probably don't need to remove it, just clean it and skip to the lubing-the-cables part

  1. Take the brake caliper off the frame:
    • Loosen the anchor bolt, which loosens the cable from the brake. Whenever you remove little screws and parts and stuff, situation them in your work area in a way that you will remember how they go back on. Seriously.
    • Unscrew the mounting bolt; now you can remove the brake from the bike frame, sort of.
    • unscrew that other thing, all the way. This makes it easier to deal with the bike without dealing with cabling: the whole cable with the end piece will fit through the hole there. You can now totally get the brake away.
  2. Clean the whole brake caliper. Try to get as much gunk as possible out of the moving parts. If you are using a solvent, you should probably remove the brake pads to protect their rubber.
  3. Lube up those moving parts, wipe off any excess oil on the caliper. Give it a squeeze. It should feel a lot more springy and responsive than before.
  4. Put the brake pads on, if you took them off, then screw the mounting bolt back in through the brake, attaching it to the frame like it was. Make sure it is centered.
  5. There should be a few inches of housing on the cable, from that unnamed thing we unscrewed earlier to a little braze-on on the frame. Roll that whole unit back up the cable. Wash the cable a little bit and then rub some lube on it.
  6. Pull the cable through the slot where that unnamed piece unscrewed from (see picture) and re-tighten the unnamed screw-thing. Make sure the cable housing is situated properly.
  7. Using pliers or tightly-gripping leathery man-fingers, pull the cable taught before re-tightening the anchor bolt from step one. You'll want to squeeze the brakes tight as you do this, but not too tight. You'll get a feel for it. You want them wide enough to get the wheel back through, but tight enough that they brake effectively when you pull the lever. You also want to make sure there definitely is no slack in the cable.
At this point, you have either:
  • successfully overhauled one or both of your brakes
  • stopped reading out of boredom
  • continued reading but are completely confused
  • made a giant mess and have rendered your bike unrideable
Either way, I hope you've learned a valuable lesson! . . .

Gear Dérailleur Overhaul

Man, I don't even want to talk about this. I totally botched this one. I need to do a total, total overhaul, or maybe I need some new cables and housings--hell, I don't know. My front dérailleur won't shift to save my life (literally). Anyway, the key for fixing your shifting problems is probably the same principle--clean and re-grease everything, including (especially) the cables, then pull the cables taught and re-clamp them.

Then you're going to want to fine-tune the shifting.. there's a couple little screws that are the limiters, they define how far the dérailleurs can move, if you can't shift to your lowest gear, loosen the L limiter. If you can't shift to your highest, loosen the H. My shifting problems are deeper than this, so the second half of my day was just an exercise in frustration.

Lubrication

Oh, yea don't forget to lube up the chain. There are various different kinds of chain lubricant based on different situations, like weather and road conditions, but I'm using Tri-flow because that's what I have. The trick with lubing your chain is to put just one drop on each link, then when that's done, wipe off the whole chain. Excess oil on the chain will just attract dirt.

Next week: lessons learned, and where to go from here?

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