Reusable master chain link (several brands): Makes removing and putting on your chain a breeze (for cleaning, lubrication or even untangling it from your frame when you drop your chain and it jams in your cranks). You no longer need a chain-breaker tool.
Frame pump: Topeak Road Morph – works like a mini floor pump. T-handle, fold-out foot-peg and thumb-lock head let you pump up to 100 psi (7 atm, 700 milliBar) without a struggle or risk of bending your Presta valve stem (also adapts to Schrader valves). It’s been called “the smug pump” by cyclists who don’t have one (and wish they did). I’ve been using mine since 2005.
Bug bites and stings: Therapik is a 9v battery-powered device that uses scientifically proven infrared heat therapy to treat painful stings and itchy bug bites. I’ve been stung by bees often enough while biking to carry one with me.
Heat-shrink tubing: great for keeping cable ends from fraying. Lighter than traditional metal crimp-on caps for cables, easy to remove when you want to, requires less skill to install than soldering cable ends or crimping metal caps.
Merino wool base layers, socks, arm-warmers, full-fingered gloves. Merino wool is non-scratchy and machine-washable. Wool doesn’t stink like synthetics, breathes well and keeps you warm even when wet. Lightweight merino wool base layers work great for cool weather/high altitude. Zip-T neck undershirts keep your carotid arteries warm, which make you feel warmer than if they were exposed to cold air. On the downside, wool can be saggy, which is why I still wear synthetic jerseys, lycra shorts and synthetic knee/leg warmers.
Be-seen lighting: A UK study said that some 60% of automobile-bike collisions happened because the motorist couldn’t see the oncoming cyclist in daylight and turned into them. Other studies say “Bio-Motion” (lights attached to a moving body part) makes it clearer to motorists that the lights they see are (on) a human being. I now use blinkies always—day or night—mounted onto a reflective runner’s wristband strapped to my ankle: a white one facing front, a red one facing back.
Garmin Varia RTL510: not just a long-running tail-light, it also detects cars approaching from behind and gives audible and visual (when paired with a compatible GPS, such as my Hammerhead Karoo) alerts to warn you.
Aftershokz Trekz Air bone-conduction headphones: lets you hear from an audio source without blocking ambient sounds like important traffic noises. I use it with my Hammerhead Karoo GPS (which has no speaker) and Garmin Varia radar for both audio alerts from the Varia and audible turn-by-turn directions from the Karoo.
Gel-padded shorts – the gel pad is too thick and retains heat.
Polypropylene as a base layer fabric – feels greasy after many washings, retains odors. Thermax costs the same and performs better. Merino wool is even better: not scratchy, warm when wet, doesn’t smell.
Rain jackets without “pit zips” – no matter how “breatheable” a fabric is (even GoreTex), it won’t fully cope with the heat and perspiration you generate from cycling. Underarm zippers and vents on the back help tremendously.
Packable full-size bike: S&S Machine Bicycle Torque Couplers (BTC™) – allow a full-size frame to disassemble and fit into a 26”x 26”x 10” case for long-distance transport. Rigorous tests demonstrate that BTC equipped tubes are stronger and stiffer than the unmodified tubes. My regular road bike has BTCs on it and feels and performs just like a normal bike.
Commuter bike: Brompton – folds/unfolds completely in < 15 seconds. Compact enough when folded to stash under a cubicle desk, and go as a piece of carry-on luggage on trains and buses.
Hammerhead Karoo: Big, bright color screen; WiFi, Bluetooth and ANT+; runs on Android. I got it after being annoyed with several generations of Garmins. DC Rainmaker’s early preview warned me that most new sports GPSes (looking at you, Wahoo, Lezyne, et. al.) took about 2 years from debut to reach a stable, usable state, so I was prepared as an early adopter. Despite some setbacks with battery drain and lost recordings, I’m happy with it and have no regrets giving up my Garmins.
LoadMyTracks is freeware from ClueTrust.com for Mac OS X which transfers data between GPS devices and Macs. It can save GPS data in GPX and KML format. TrackRunner, donationware from Laniesoftware works with LoadMyTracks to display tracks on Google Maps (without using a web browser), as well as graph and keep a log of your performance.
GPS Visualizer is website which will map uploaded GPS data onto satellite/aerial photos, as well as produce elevation profile graphs, for free. It can also convert GPX files into KML/KMZ to display in Google Earth and Google Maps.
A guide to chain wear measurement tools.
Chain-suck – an extensive and thorough discussion and investigation of its causes and how to prevent it.
Indexed steering – what causes it and the solution to the problem.
Soul bikes gears/drivetrain calculator. It’s quite flexible and elaborate enough to initally appear confusing; however, the interface becomes clear with use.
If you believe that “aluminum is harsh” or “steel fatigues and becomes soft” you need to read Sheldon Brown’s page on bicycle frame materials. For greater depth, read the 7-part series on metallurgy for bike frames by Strong Frames.
The 15% deflection rule-of-thumb for tire inflation pressure: Read how we may be overinflating our tires and why you might want to run front tires at lower pressures than rear tires. My tire pressure calculators page has one based on the article, as well as one based on Michelin’s recommendations, and a link to Rivendell’s chart.
Product images are © their respective manufacturers.