The Bicycle as Backup Transport
Gas is finite. Cars break in ways that require parts and shops. A bicycle needs only basic tools, a few inexpensive parts, and physical effort. If your goal is mobility in a grid-down scenario, a maintained bicycle in your garage is a more reliable asset than a car with questionable fuel supply.
This guide covers the maintenance skills that keep a bicycle operational under regular use.
Flat Tire Repair
Supplies Needed
- Tire levers (3)
- Spare inner tube or patch kit
- Portable pump or CO2 cartridge
Finding the Cause
Before installing a new tube, find what caused the flat. Inflate the tube slightly and listen/feel for the leak. Check the inside of the tire at that location for embedded glass, wire, or thorns. Run your fingers carefully around the inside of the tire — a small shard will cut your finger, which tells you exactly where it is. Remove the cause before installing the new tube, or you will flat again immediately.
Tube Change
Chain Maintenance
The Chain Wear Test
A worn chain stretches and accelerates wear on the entire drivetrain (cassette and chainrings). A chain wear indicator tool ($5) is the right way to check — or measure 12 complete links. They should measure exactly 12 inches. If they measure 12-1/8 inch or more, replace the chain.
Cleaning
Remove built-up grime from the chain with a chain cleaning tool (clips onto the chain with solvent inside) or by soaking a shop rag in chain cleaner or degreaser and wiping the chain as you backpedal.
Do not clean with WD-40 — it is a solvent and water displacer, not a lubricant. WD-40 removes oil from the chain.
Lubricating
- Apply chain lube to the inside of the chain (the rollers, not the outer plates)
- Backpedal while applying — one drop per link along the lower run
- Allow to penetrate for 2-5 minutes
- Wipe off all excess with a dry rag — surface lube attracts dirt, internal lube prevents wear
Dry lube (paraffin-based, clear): Best for dry conditions. Less messy. Wash off more easily. Wet lube (oil-based, dark): Best for wet conditions. Stays on longer. Attracts more grit.
Brake Adjustment
Pad Wear Check
Look at the brake pad surface. Most pads have wear indicators (grooves that disappear when the pad is worn out). Replace pads when wear indicators are gone or when less than 3mm of pad material remains.
Rim Brake Alignment (V-brakes and caliper brakes)
The pad should hit the rim squarely — not above the rim (it will hit the tire and cause a flat) and not below the rim (it will hit the spokes, catastrophic failure). To adjust: loosen the brake pad bolt, reposition the pad, retighten.
Toe-in: The front of the pad should contact the rim slightly before the rear. This prevents brake squeal. Adjust by bending the brake arm slightly or using a shim at the pad.
Centering the caliper: The two pads should touch the rim simultaneously. Most calipers have a centering adjustment screw (usually on top of the spring). Adjust until the brake is centered.
Cable Adjustment
If levers pull all the way to the bar before braking firmly: the cable is too slack. Turn the barrel adjuster (at the lever or brake body) counter-clockwise 2-3 turns. If that does not create enough adjustment, pull the cable through the pinch bolt (loosen, pull, retighten).
Derailleur Adjustment
Front Derailleur
The cage should move the chain between chainrings without rubbing and without dropping the chain off either end. Limit screws (marked H and L on the derailleur) stop the cage at its inner and outer travel limits.
H screw (high gear): Adjusts outer limit. The cage should barely clear the chain in the large chainring. L screw (low gear): Adjusts inner limit. The cage should barely clear the chain in the small chainring. Cable tension: Adjust the barrel adjuster until shifts are crisp.
Rear Derailleur
Same principle. H and L limit screws prevent the chain from throwing off the small or large cog.
B screw: Adjusts gap between jockey wheel and cassette cogs. Should be 5-8mm gap for most cassettes.
Most shift problems are cable tension issues, not limit screw problems. Before adjusting limit screws, verify the cable is properly tensioned.
Essential Toolkit for Bicycle Field Repair
| Tool | Notes | |------|-------| | Tire levers (3) | Plastic preferred (won't damage rim) | | Portable pump or CO2 | CO2 is faster; pump works indefinitely | | Spare inner tubes (2) | Match your tire size exactly | | Chain lube | Small bottle | | Chain master links (3) | Carry the size for your chain | | 4, 5, 6mm allen keys | Most bolt sizes on a modern bike | | 8, 10mm open wrench | Axle nuts on non-quick-release wheels | | Small Phillips and flathead screwdriver | Limit screw adjustment | | Patch kit | For backup tube repair |
Fits in a small saddle bag mounted under the seat. Weighs under a pound.
Sources
Frequently Asked Questions
Why should preppers care about bicycles?
Bicycles require no fuel, no electricity, minimal maintenance, and can be ridden on most surfaces. In a fuel shortage or grid-down scenario, a functioning bicycle extends your effective range from walking distance (3-5 miles/day under load) to 30-50+ miles/day. A well-maintained mountain bike is among the most valuable grid-down transport assets.
What spare parts should I stock for a bicycle?
Inner tubes (2-4 matching your tire size), tire levers (3), patch kit, chain master links (3-4), brake pads (one full set), brake/shift cable and housing (one set each), chain lube. This covers 90% of roadside and field repairs.
How often should I lubricate a bicycle chain?
Wet or muddy conditions: after every ride. Dry conditions: every 100-150 miles or whenever the chain sounds dry. Use wet lube for wet conditions, dry lube for dry conditions. Wipe off excess after application — oil on the chain attracts grit that grinds the drivetrain.