Complete Bicycle Mechanics and Repair: From Flat Tire to Full Overhaul
The bicycle is the most efficient human-powered transportation ever invented. This campaign covers bicycle anatomy, maintenance, repair, and improvised solutions.
Chapter 1: Bicycle Anatomy
System
Components
Function
Maintenance Frequency
Drivetrain
Chain, chainrings, cassette, derailleurs
Converts pedaling to wheel rotation
Clean/lube every 100-200 miles
Braking
Brake levers, cables, calipers/pads (or disc)
Stopping
Check pads monthly, replace when worn
Wheels
Hubs, spokes, rims, tires, tubes
Rolling contact with ground
Check spoke tension monthly
Steering
Handlebars, stem, headset, fork
Direction control
Check headset tightness monthly
Frame
Main triangle, seat stays, chain stays
Structural backbone
Inspect for cracks annually
Seating
Saddle, seatpost, seatpost clamp
Rider support
Adjust height for comfort
Pedals
Pedal body, spindle, bearings
Foot-to-crank interface
Grease bearings annually
Bottom bracket
Spindle, bearings, cups
Connects cranks to frame
Service annually
Chapter 2: Essential Repairs
Repair
Difficulty
Time
Tools
Frequency
Fix flat tire
Very low
10-20 min
Tire levers, patch kit, pump
As needed
Adjust brakes
Low
10-15 min
Allen keys, cable puller
Monthly
Adjust derailleurs
Moderate
15-30 min
Screwdriver, Allen keys
Seasonally
Replace chain
Low
10-15 min
Chain tool
Every 2,000-3,000 miles
Replace brake pads
Low
10-15 min
Allen keys
When worn thin
True a wheel
Moderate
20-40 min
Spoke wrench
As needed (wobble)
Replace cables
Low-moderate
20-30 min
Cable cutters, Allen keys
Annually
Overhaul hubs
Moderate-high
1-2 hours
Cone wrenches, grease
Annually
Replace bottom bracket
Moderate
30-60 min
BB tool, grease
Every 2-3 years
Flat tire repair: 1) Remove wheel from bike (quick release or axle nuts). 2) Deflate tire completely. 3) Insert tire lever under bead, hook to spoke. 4) Insert second lever 4-6 inches away, slide around rim (unseats one side of tire). 5) Pull tube out. 6) Inflate tube, listen/feel for leak. 7) If can't find: submerge in water (bubbles show leak). 8) Mark leak location. 9) Rough up area around leak with sandpaper (from patch kit). 10) Apply glue, let dry until tacky (2-3 minutes). 11) Apply patch, press firmly (60 seconds). 12) Check inside of tire for cause (thorn, glass, wire). 13) Partially inflate tube, insert in tire. 14) Seat tire bead on rim (use hands, not levers if possible). 15) Inflate to recommended pressure. 16) Reinstall wheel.
Chapter 3: Drivetrain Maintenance
Task
Frequency
Tools
Time
Impact
Clean chain
Every 100-200 miles
Degreaser, rag, brush
15 min
Extends chain life 2-3x
Lube chain
After cleaning or rain
Chain lube (wet or dry)
5 min
Smooth shifting, less wear
Check chain wear
Monthly
Chain checker tool or ruler
2 min
Prevents cassette damage
Adjust front derailleur
As needed
Screwdriver, Allen key
15 min
Clean shifting
Adjust rear derailleur
As needed
Screwdriver, Allen key
15-30 min
Clean shifting
Replace chain
Every 2,000-3,000 miles
Chain tool, new chain
10 min
Prevents drivetrain wear
Replace cassette
Every 2-3 chains
Cassette tool, chain whip
15 min
Smooth pedaling
Chain cleaning: 1) Shift to smallest chainring and smallest cog. 2) Apply degreaser to chain (or use chain cleaning tool). 3) Scrub with stiff brush (old toothbrush works). 4) Wipe chain clean with rag (backpedal through rag). 5) Clean chainrings and cassette (brush + degreaser). 6) Rinse if needed (water, not high pressure). 7) Dry chain thoroughly. 8) Apply lube: one drop per link, backpedal slowly. 9) Wipe excess lube off exterior (excess attracts dirt). 10) Wet lube for wet conditions; dry lube for dry conditions.
Chapter 4: Wheel Truing
Issue
Cause
Fix
Tool
Lateral wobble
Uneven spoke tension
Tighten spokes on opposite side of wobble
Spoke wrench
Radial hop
Uneven spoke tension
Tighten spokes in high area, loosen in low
Spoke wrench
Broken spoke
Impact, fatigue
Replace spoke (match length and gauge)
Spoke wrench, spoke
Loose spokes
Vibration, under-tension
Tighten all spokes evenly
Spoke wrench
Wheel truing procedure: 1) Mount wheel in truing stand (or flip bike upside down, use brake pads as reference). 2) Spin wheel slowly. 3) Identify wobble: where rim moves left or right relative to reference point. 4) Find the center of the wobble. 5) Tighten spokes on the OPPOSITE side of the wobble (pulls rim toward that side). 6) Turn spoke nipple 1/4 turn at a time (small adjustments). 7) Tighten 2-3 spokes in the wobble area (center spoke most, adjacent spokes less). 8) Spin and check. 9) Repeat until wobble is gone. 10) Check spoke tension by squeezing pairs (should feel similar tension throughout).
Chapter 5: Improvised Repairs
Problem
Improvised Fix
Materials
Duration
Flat tire (no patch)
Stuff tire with grass, leaves, cloth
Natural materials
Get home (rough ride)
Broken chain
Remove damaged link, rejoin (shorter chain)
Chain tool (or rock + nail)
Functional (skip gears)
Broken spoke
Tape broken spoke to adjacent spoke
Tape, wire
Get home (wheel wobbles)
Broken brake cable
Use remaining brake only (front preferred)
N/A
Careful riding
Bent derailleur hanger
Carefully bend back with adjustable wrench
Wrench
Functional shifting
Loose headset
Tighten with available wrench
Wrench
Proper fix later
Torn tire sidewall
Boot with dollar bill, duct tape, or cardboard inside tire
Paper, tape
Get home
Reference Card
Keep the chain clean and lubed (a clean, lubed chain extends the life of every drivetrain component). 2. Check tire pressure before every ride (proper pressure prevents flats and improves efficiency). 3. Learn to fix a flat (the single most common repair; practice at home before you need to do it roadside). 4. Quarter turns only (when adjusting spokes or derailleurs, small adjustments prevent overcorrection). 5. Replace chain before it's worn (a worn chain destroys cassette and chainrings; cheap chain saves expensive parts). 6. Front brake has more stopping power (70% of braking force is front; learn to use it without flipping). 7. Carry a basic kit (spare tube, tire levers, pump, multi-tool; these fix 90% of roadside problems). 8. The bicycle is the most efficient vehicle (4x more efficient than walking; the best human-powered transportation ever invented).
