Another way to keep you head warm, but ventilated too: I buy large silk scarves at thrift shops and if it is just somewhat cold, I wear the scarf tied around my head/hair and put the helmet on top; the sild is thin enought to fit nicely under my helmet with the hair. If it is really cold I wear the on-the-head-scarf and I will wrap the helmet itself in a large scarf, thus blocking the vents. I find the second way very warm, but not too sweaty (at least for me!).

An added bonus: not only do people get to look at me and wonder what an "old fat lady" is doing on a bike, but they get to sometimes look at the scarf and have a good laugh!--and the bright colors make me feel good too.

If you are not into gaudy scarves, you could find some lightweigth silk in a solid color at a fabric store and then cut, fold and mutilate it to your own ways.

++ Clean and relube chain every 250 miles. It's amazing how much easier it is to ride after a relube.

++ check tire pressure at least once a week, better every 3 days.

Do a 15 second quick check of the bike before you ride. Squeeze the tires to check pressure. Spin each wheel while holding it up and listen if the rims are rubbing against the brakes. Also look for broken spokes. Then squeeze the brake levers to test the brake systems. While you have the rear wheel up, crank the pedals once by hand to make sure you're in the right gear and the chain is OK. Get on and go!

AWESOME THREAD! Thank you

- carry a mobile phone with you

And after you replace your tube, you can put your OLD tube into your bagie, stuff it into your jersey and keep on trucken. No need to litter, you know!

I like to clean my chain in the back yard, over the grass. If you do it over cement, you could drip oil and grease and cause permanent stains.

When you are putting on a new tire, inflate it a few pumps and then check to see that the tire is seated properly on the rim. After that you can continue to pump it up to your desired pressure. As I discovered from experience, if you don't do this, you run the risk of the tube pushing the tire off the rim. The tube would then likely explode.

I clean my chain on the bike with newspaper clothespinned to the back spokes to keep the back rim clean and let everything drip on a newspaper lined oil drip pan purchased on the cheap from an auto parts store. No drips on the cement OR the grass.

Preflight check for minimal sporty ride.

1) Tire levers and 15 mm wrench.
2) 2 spare innertubes - I hate patching -
3) Small pump - cheap ... just to get you by till you hit the next gas station
4) Gel packs - because you never know when to bonk
5) Hydration - you are a tomato ... a ripe one that can pedal.
6) Cel phone - you only have 2 spare tubes and no chain tool afterall
7) Wallet - Insurance - Drivers License - Bank Card - Credit Card - 40$ in cash.

When the season starts ... go for shorter rides first to to dress accordingly. In any case you will not be overdressed or the opposite for a long period of time.

Pre nurishment - lazy as I am, two large cups of coffee and one large spoonful of honey and peanutbutter.

First the peanutbutter and wash it down with the coffee. Works wonders for me

Make a friend on every ride. If you ride the same routes, in no time at all people will get used to seeing you and before you know it nobody will jack with you either.

Bring food of some sort for rides longer than 2 hours. Also consider bringing Gatorade or some sports drink along to compliment water on said long rides.

Let air out of you mountain bike tires to increase suspension and make ride more comfortable over very rough terrain.

Pre ride inspection:
Make sure your wheels rotate before you leave.

Occasionally check your headset to see if it is loose. Apply your front brake and then grab the area where the fork enters the headtube. THere should be no play as you rock it to and fro. If there is you need to tighten your headset, before you have a bad accident or damage your bike.

Keep a journal of your ride.
If you are not too concerned about weight bring along a small camera. You never know when a photo opportunity might arise.
I started a bike journal about a year ago. At first I only recorded distance, averages, and a general description of the route. After a while I expanded to general observations on my day. Finally, I started adding photos to the mix. At the end of the year I had a fairly detailed record of my experiences. I printed it out and plan to do an edition each year.
As you get older and start to forget everything, you can always refer back to the journal for clarification.

I always spin my wheels before a ride like others have mentioned.

I always check my brakes by going through a little pre-ride routine.

Stand beside the bike and roll it forward slowly (only a few inches are needed) then apply the front brake, the rear wheel should lift without having to squeeze the lever too hard. Roll the bike backwards and apply the back brake. The front wheel should lift off the ground without having to squeeze the lever too hard. There should also be plenty of room between the lever and handlebar when the wheels raise. I also always check the brakes when I start riding, before I need them, just looping around the parking lot or whatever and making sure they feel right.

If your tubes have presta valves with adaptors for schrade type pumps, don't use the dust caps. When you unscrew the caps, the valve core can be unscrewed along with them. My tubes are slimed - I don't know if that's the cause or not.

EDIT: I mean, the brass adaptor unscrews along with the dust cap, taking the valve core with it. Hope that makes more sense.

Weight Weenies will want to make sure to pack only single-ply.

Somone mentioned a powerbar wrapper as a tire boot - good fix. But what I carry for a tire boot is better. A simple dollar bill. Actually I carry a five dollar bill. On the occaisional ride where I find myself in need of jingle to spend, I can spend it. And as a tire boot, nothing is tougher.

Mtn Bike
~Small amount of duct tape wrapped around a 5mm allen wrench. Many rides have been saved by this magical product
~Carry a chain tool and a couple of chain links or master links
~A spare derailleur hanger
~ If you don't know what Poison Ivy looks like, learn. Or making that emergency stop in the pucker can turn ugly. I don't get Poison Ivy, so don't follow my lead.

Road
~Don't draft off the back of Hay trailers. Your eyes will take it hard.
~Don't draft off any motorized vehicle and then jump out of the slipstream. Drop back slowly to keep control. I almost ended up in the river once when I forgot that little hint.
~Don't alter your route after telling your wife where you are headed and then call her for help from East Gish wherever 60 miles from home and you are supposed to going out that night. Better yet, just circle around the driveway that day so she can keep an eye on you.

General
~A clean bike is a happy bike
~Over lubing is possible. Learn to do it right.
~WD 40 is not a lubricant. It beats a blank, but not by much.
~If you have a good LBS in town, support it.

The four truths I've found in these last five years of riding a lot:

Fix stuff that goes wrong as soon as you get back from a ride, or you'll likely forget 'til you start the next ride.

Whatever you decide to tour with, go back and cut the volume in half.

Equipment's overrated; decent stuff is important, but it's the engine's that counts.

Don't ride with whiney people. (This one might just be a personal preference-maybe you like whiney people?)

have robotic legs :D

Take a pencil and cut it in half, then wrap duct tape around it till it suits your future needs and place it in the little side compartment in your saddlebag. I use duct tape in conjunction with left over Tuffy liners from whatever bike I had used it for; by patching blown out sidewalls on tires (a generous size). Save my butt and some friends of mine a few time. Always squeeze the contact cement tube from the bottom up to take out any air bubbles after patching tubes; on the road or at home (this ensure you that the next time you have to use it; it won't be dried up). Always carry three tire irons with you when a new tire is being used.

If the weather looks perfect, don't assume it's going to stay that way. Go out and ride.

Always carry an old handkerchief or two. Cleans glasses when they get sweaty or rained on. Cleans grease off hands.
Last weekend when I realized that I forgot my skullcap, I folded up the handkerchief and put it in my helmet to block the vents and keep my head from freezing. Didn't help my ears but ....

When your bike needs a repair, buy the tool and the part, then fix it yourself. If you buy a tool and a part at full price at a good LBS, they will give you advice on doing the repair.

Keep spares of everything that tends to wear out--chains, tubes, tires, cassettes, cables, housings, etc. That way, you're never dependent on the LBS being open when you need a repair.