Spokes and Valve Stem
Test: Check for loose spokes and valve stems. Otherwise, spokes may be rubbing the nipples.
Fix: True your wheel. Grease the nipples and spots where spokes cross. Matte-black spokes are apt to creak. If the valve stem wiggles, wrap it with electrical tape.
Wheel Skewers
Test: Open, then retighten both skewers.
Fix: Lightly grease the frame dropouts and tighten your quick-release. And not just to kill the noise: A wheel could pop out while you're riding.
Pedal Bearing and Cleats
Test: Ride with another set of pedals.
Fix: Grease your cleat. If the noise persists, retighten the pedals. If the sound is more of a pop, try cleaning and replacing worn bearings.
Seatpost and Saddle Rails
Test: Pedal out of the saddle to see if the noise stops.
Fix: Grease your rails and post. Use carbon paste instead of standard grease for carbon-fiber parts.
Bottom Bracket
Test: Listen for a creak from below while riding. If chainring bolts aren't tight, they will click.
Fix: Remove your cranks and feel the bearings. If they turn smoothly, remove the bottom bracket to clean and regrease the threads. If the frame's bottom-bracket opening edge is rough, take the bike to your shop.
Handlebar and Stem
Test: Lube all the bolts and contact surfaces.
Fix: Clean, then grease contact surfaces and the steerer tube (use carbon assembly paste for carbon parts).
Hubs
Test: Wiggle your wheels to feel for side-to-side play. Hold the hubs and spin the wheels to ensure the bearings roll smoothly. If you suspect the rear wheel is the culprit, also check that the cassette is tight and the freehub bearings are in good shape.
Fix: Most hub bearings aren't easily tightened or cleaned. Take the wheel to your shop.
Headset
Test: To identify continuous clicking, ride with no hands. To check for occasional creaking, stand over your top tube and keep the front wheel planted. Then grab the drops and pull up on one while pushing down on the other
Fix: Clean and grease the bearings. If the head-tube surface is uneven, take the bike to your shop. For clicking, grease the cable housing mount.
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