WAYS TO RESTORE YOUR MOUNTAINBIKE
Hi, Doctor, my bike is here for it's yearly check-up. |
SPORTS MEDICINE FOR YOUR BIKE
Like your body, your bike also needs the proper attentionon to be on the cutting edge of performance. It needs to be maintained under the watchful eye of a bike doctor. Be it a bike mechanic or you yourself. It's only after performing certain tests that you or the bike mechanic can discover which areas need more attention. Fixing weaknesses on the bike is much easier and faster than overcoming serious maladies. This is how to give your bike a physical before the next ride.
Integrity: Steady a pencil off a caliper, fork leg or frame tube and spin the wheel. Locate the center of the
wobbles. Pull the rim in line by loosening and tightening the same side and opposing spokes. High spots can be fixed by equally tightening the respective groups of spokes. Flat spots necessitate a new rim.
Foot print: Glance around each sidewall for serious abrasions. Look over the tread surface and pull out goat heads, thorns, nails or Earth First! tree spikes. Recheck tire pressure before each ride. If you don't know what pressure to run, start with 2.5 bar and fine-tune up or down in 5 psi increments.
Steady power: Use a wire brush to clean the sprockets and the top, bottom and both sides of the chain. Place a drop of chain lube on one pin at a time. Backpedal for a minute and watch for irregular chain movement around the bottom G-pulley wrap (indicating a bad link). Wipe excess oil with a rag.
Lube shot: Use the plastic SPD socket to unthread the pedal cartridge. Pack the pedal cavity with grease and rethread the cartridge. As the excess grease is forced out, it pressure-feeds the cartridge bearings. Place a drop of lube at the outer corners of each of the latching mechanism's spring-loaded pivots.
Loose joints: Engage the front brake and grasp between the lower bearing cup and fork crown with a forefinger and thumb. Rock the bike fore and aft and feel for movement. Rock the wheels up and down and back and forth and feel for play in the hubs, swingarm or suspension linkage. Adjust as necessary.
Shock therapy: When taking an air reading, pressure from inside the shock body is released into the innards of the shock pump and lowers the actual reading by 5 psi to 15 psi. Pump back to the desired number. With a marker, write the pressure you are running on the fork leg, reservoir or frame.
Brake surgery: Unhook a caliper spring and the opposing pad will touch the rim. Check pad angle and height. Do the same on the other side. Modern calipers run little or no toe-in. Pads that have taken a permanent set and are stubborn to adjust can be trimmed with a knife for tire
clearance or toe-in.
Instant reflexes: Twist the bar lever barrel adjusters all the way in and then back out two turns. Set the preferred brake lever play by adjusting the cable inside the caliper fixing clamp. There is now plenty of barrel adjustment left at the lever to loosen or tighten brake play while riding.
Shock absorption: Clean built-up dirt before lifting the fork dust caps or boots. Clean and inspect the fork seals and around the stanchions. Bad nicks can be cleaned with a jewelers file and 600-grit wet-and-dry. Use fork oil or de-friction lube to lubricate the seal top before reinstalling the boot.
