Let me share with you here 18 years of mishaps and battle with Murphy. This being a bike repair blog, I will go one up and recommend the preventive measures to avoid dealing with the Murph man.
1- If you leave your pump or spare tube behind, you will get a flat. The risk grows with the potential distance you will have to walk if stranded. Darkness, rain, hurricanes, squadrons of biting mosquitoes will also contribute to the odds of you being stuck with a dangling tire from your rim.
Solution: Always have some kind of working tire pump with you and a spare tube of the proper size.
2- Your crank arm will fall off in the middle of nowhere. If Murphy is really into you, it will happen in a desert and you'll risk dying from the ensuing ordeal.
Solution: Check your crank arm bolts for tightness every so often, especially before a big ride. To eliminate all risk, carry a
crank wrench.
3- Even though you come across it all the time when looking for something else, you will not find the 13mm socket when you absolutely need it. This applies to any other tool that is always in your way but magically vanishes when you somehow desperately need it.
Solution: Be tidy and always put your tools away in their proper place right after you are done with them.
4- That air bubble squeezing itself out between the tire and the rim will explode milliseconds before you reach the air valve to let the air out.
Solution: Put in only 10 pounds of air in the tube and stop. Check the tire on both sides to see if it's properly seated in the rim. Make corrections if necessary and resume inflation without fear of going deaf or making your spouse think you just fired the shotgun in the garage for fun.
5- If you know how to use a chaintool, your chain will break if you don't carry one. The longer the chain, the bigger the risk.
Solution: Always carry a chain tool even if it's a cheap one.
6- The spare tube you bought has a Presta valve, you don't have an adapter because you didn't know it had a Presta valve. You now curse the very existence of Presta valves and who ever came up with that bright idea to the 8th degree.
Solution: Always check tubes out of the box before you just toss them in your bike bag. Make sure you got the right thing before you need it in an emergency, then store it away.
7- You willingly use inner tubes with a Presta valve (curse them %$#&*@ things) but you do not have an adapter when your only source of air is a service station pump.
Solution: Always have an adapter already screwed on one of your tires air valve.
8- A simple repair job will always take up a lot more time than you thought it would.
Solution: Plan for twice the amount of time you think it will take. Be proactive and actually triple it.
9- When installing or repairing an expensive derailleur you will be stomped by a missing or broken $0.25 doodad that you can't find or buy just about now.
Solution: Keep on hand a few nuts and bolts, cable stoppers or any other small thingamajig that gets overlooked on any repair job until you absolutely need it. Trash bikes are great for those.
10- The cheap brake pads that were everywhere growing like weeds are nowhere to be found now that you need to replace a set.
Solution: You see a good deal on brake pads, cables or any other stuff that your bike goes through anyways? Buy them now, you'll use them eventually at some point in time. Don't hoard, just buy what you'll need.
I'm sure there are a tons of others, so feel free to leave them in the comments.
Until next time, ride safe and Godspeed.
Gerry :)