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My brakes don't work properly. When used, they make noises and don't stop the bike.
Every time you try to slow down, your brakes squeak. If the brakes are squeaking, they might be wet. To fix them, dry them off with a microfiber cloth or paper towel. Make sure there is no material left behind from the cloth. If the brake pads are covered in oil, see Oil covered discs/pads below.
If the brakes are rattling, the disc may be misaligned causing the pads to squeeze with unequal pressures. Remove the disc brake and make sure it is not warped or cracked. If the brake pads are warped or cracked, the pads need to be replaced, to do so please refer to Triace A310 Brake Pad Replacement.
Oil Covered Discs/Pads
Remove both brake pads and discs. Sand down the pads with fine sand paper. Soak both the pads and discs in rubbing alcohol or degreaser. If you used rubbing alcohol, bake the pads in the oven at 250 degrees Fahrenheit to burn off the absorbed rubbing alcohol. Wipe down the discs until dry, making sure to avoid bodily contact with the face of the disc that comes in contact with the pads. For a complete walkthrough please see Triace A310 Brake Pad Replacement.
Dirty Brake Pads and Discs
Remove brake pads and disc(s). Use a damp microfiber cloth or paper towel to wipe clean. Once dirt is removed, make sure to completely dry brakes and pads being sure not to touch the face of the disc that comes in contact with the pads. For a complete walkthrough of removing the brake pads, please see Triace A310 Brake Pad Replacement.
No Tension in Brake Cables
Loosen the bolt on the problem brake and manually pull the cable tight. When it is as tight as you want it, tighten the bolt back onto the cable. For a complete walkthrough please see Triace A310 Brake Cable Maintenance.
Every time I pedal, the chain slips or snaps.
Broken or Loose
For this repair, you will need to purchase a chain tool. Begin by removing the chain from the bike while wearing disposable gloves. Push the pin out by screwing the pin of your chain tool in just before the pin comes out. Be very carful to not push the pin all the way out. Snap the two pieces apart then click the two links back into place with the pin facing you. Push the pin back into both links until it comes out evenly on both sides. Grab the chain on each side of your newly connected links and move it side to side to loosen up the new connection. Re-attach the chain to the bicycle. For a complete walkthrough see, Triace A310 Chain Replacement.
It is hard to move the bike when I pedal and more difficult to turn.
Tube has a Hole in it
Turn the mountain bike over onto its back, undo the quick release lever, and remove the damaged tire. Remove the tube from the rim of the wheel by locating the valve stem for air input and choosing a spot on the opposite side of the wheel. Using the beveled end of a tire iron, separate the tire from the wheel rim and latch the iron onto a spoke. Repeat with a second tire iron about an inch away from the first tire iron. Keep doing this around the wheel until you can fully remove the tube from inside. Check the tire for any debris. Take the damage tube and submerge it in water to locate the hole (air bubbles will be flowing from the hole). If there is a tear, you may need to purchase a new tire tube. Wait for the tube to completely dry then apply a patch to the hole. Wait for the patch to bond to the tube. Place the tube back into the tire and secure the tire back onto the bike frame making sure that it is firmly attached. Proceed to pump up the newly repaired tire tube. For instructions on how to remove your tire, please see Triace A310 Tire Removal.
Whenever I change the back gears, the chain slips or I hear a cracking sound.
Chain Slipping off Gears
If the chain is loose, see low tension section. If the cassette teeth are worn, replace the cassette. To replace the cassette, there is a very helpful guide at wikihow.com.
I can't switch gears easily and I can't switch to some gears at all.
Not Switching Gears
The derailleur might not be switching gears because it is out of alignment. See the "Missing" gears section below.
"Missing gears" can be caused by the derailleur being out of alignment. Shift your chain into the largest chain ring and smallest cog, then loosen the cable clamp bolt located where the cable attaches to the derailleur. Look for the high and low adjusters on the derailleur, marked H and L. Adjust the high-gear screw by turning it until the jockey pulley,(one of the gears contained within the derailleur), lines up with the smallest cog. Your chain should move smoothly around the cog and pulleys when you turn the pedals. To align with the largest cog, pedal forward and push the derailleur so that the chain shifts to the largest cog. If the pulley takes the chain beyond the largest cog, screw the low adjuster inward until this stops. For a video on how to do all of this, see youtube.com.
You might also need to replace the derailleur. Separate the chain with a chain tool, loosen the cable-clamp bolt on the rear derailleur, and pull the shifter cable out. Undo the hex bolt that attaches the derailleur hanger to the bike. Make sure the new derailleur is compatible with your bike’s shifters. There is a very helpful video on how to replace the derailleur on youtube.com.
Binding of the Chain
Binding of the chain can be caused by the derailleur being out of alignment, it is just a much more fine adjustment. For a full walkthrough see "Missing" gears above.