Bike Assembly

Before doing anything else, identify your pedals. Pedals are thread-directional -- the left pedal has LEFT-HAND (reverse) threads, the right pedal has STANDARD (right-hand) threads. Look for L and R markings stamped on the spindle (the axle part that threads into the crank arm). If you can't find markings: the right pedal is always on the chainring side of the bike (the side with the sprocket/gears). Why this matters: Threading a left pedal clockwise into the crank or a right pedal counterclockwise strips the threads in the crank arm. Damaged crank arm threads are expensive to repair. Set the pedals aside and don't mix them up.

For bikes where the handlebar and stem arrive separate: Apply a thin layer of grease to the stem clamp and the handlebar where they contact. Insert the handlebar into the stem clamp. Before tightening, check that the handlebar is centered -- most handlebars have a center mark. For threadless stems (most modern bikes): The stem clamps around the fork steerer tube. Tighten the stem bolts in a star pattern (alternating bolts) to seat the clamp evenly. Torque to the stem manufacturer's spec -- usually 5--7 Nm for aluminum, 3--5 Nm for carbon fiber. For quill stems (older or upright bike style): Insert stem into the fork steerer tube and tighten the quill bolt. Set height before tightening -- the minimum insertion line must be below the headtube. Handlebar angle: Set handlebars to a comfortable angle, tighten, then stand and check ergonomics before doing a final tighten. Much easier to adjust now than after riding with a stiff neck.

For quick-release wheels: Open the quick release, slide the wheel into the fork dropouts, close the quick release. The lever should close firmly enough that it leaves an impression on your palm -- if it closes with no resistance, the tension is too low. For thru-axle wheels: Thread the axle through the fork leg, through the wheel hub, and into the opposite leg. Tighten to manufacturer torque spec (usually 12--15 Nm). After installing the wheel: Check that the brake rotor (disc brake) or brake pads (rim brake) are centered relative to the braking surface. If disc brakes rub, the caliper needs to be re-centered -- loosen the caliper mounting bolts, squeeze the brake lever firmly to self-center the caliper, hold lever, tighten caliper bolts. For rim brakes: The brake pads should contact the rim squarely (not the tire, not below the rim). Adjust the pad position by loosening the pad mounting bolt.

Apply grease to the pedal threads before installation. This prevents them seizing in the crank. Right pedal (drive side / chainring side): Thread in clockwise. Start by hand to confirm it's not cross-threading before applying tool pressure. Tighten with pedal wrench to firm -- pedals tighten further under riding load, so over-tightening is rarely a problem. Under-tightening causes the pedal to unscrew while riding, which is dangerous. Left pedal (non-drive side): Thread in counter-clockwise. Again, start by hand, then use the pedal wrench. For clipless pedals (SPD, Look, etc.): Install the cleats on your shoes before your first ride. Cleat position affects knee alignment -- center the cleat under the ball of your foot, toes pointing slightly outward (most people's natural angle).

Seat height: Your leg should be almost fully extended at the bottom of each pedal stroke -- slight bend at the knee, heel on the pedal. If your hips rock side-to-side while pedaling, the seat is too high. Apply grease to the seat post before inserting it into the frame (prevents seizing and allows easy adjustment). Brake lever check: Squeeze each lever fully. The lever should not reach the handlebar before the brake fully engages. If it does: the cable has slack. For cable brakes, use the barrel adjuster at the lever to take up slack. If the barrel isn't enough, adjust at the cable pinch bolt at the caliper. Shifting (for geared bikes): Run through all gears before the first ride. Gear indexing may need adjustment after cable stretch from the first few rides. The rear derailleur barrel adjuster handles most first-ride cable stretch. Safety roll: Before riding, push the bike forward and apply each brake firmly. Confirm the wheels don't skid or wobble. Listen for rubbing or clicking that shouldn't be there.