How to store your bike during the off-season

For many cyclist winter is a sad time of the year.
In October and November I tried to bike as much as possible, but when the temperature drops below 50 the wind shear is just unbearable.

So, for us living in the unfortunate part of the country winter means off-season.

Then, you have to store you bicycle somehow, but is there something to consider?

Imagine you're storing your car in a garage for 4-5 months. Of course if you ask different people they answer differently, but they all come up with a short list of things to do.
Some may change engine oil, some will wash their cars, some would even wax it for some reason.

What about bicycle?
Is there something that really needs to be done?

One important thing is moving the derailleurs (not deraillers) toward smallest gear rings.

Do you see that in the picture? I mean move derailleurs toward the green arrows.

Top view of the front derailleur. Move your derailleur (and chain) toward green arrow direction (inward)

Rear derailleur. Move your derailleur (and chain) toward green arrow direction (outward)

This is fairly important. To understand why, you may need to know how derailleur works.
Derailleurs are nothing but guides that align your chain to remain in certain position. Wherever the derailleurs go, chain will follow.
Imagine you're shifting rear derailleur from the outer-most gear to the second to the outer-most. First, the derailleur moves (because you're shifting). The chain does not move onto the new gear right away.
It stays onto the old gear until it gets to the shifting point.

If you look closely once every few teeth of the gear has different shape. Look at the picture below.

Do you see the blue arrows and the shape of teeth is different than their neighbors? That's where the shifting happens.

The teeth of that shifting point is smaller than others, so the chain can go in-and-out of the gear smoothly. Ah~.

Ok. Now, as you noticed the derailleurs are spring loaded, meaning there are springs applying force in one direction all the time. Take a look at the first two pictures above.
Do you see the green arrows? That's the direction of this spring force.
For example, in case of the rear derailleur, the spring mechanism inside of the derailleur is always pushing it outward.

When you shift gears you apply tension to the cable (there are a cable coming out of the derailleurs. One cable per a derailleur. Check your bike) and pull the derailleur toward the red arrow direction.

Inside the shifter (near your finger tips), there's a notched mechanism so it lets you pull the cable only so much, and that makes the derailleur stay in a certain position. (Imagine you're shifting from outer-most to second to outer-most, yet your derailleur ends up between some other random position. This notched mechanism prevents it from happening. It's like the derailleur is moving step-by-step and the size of this step is fixed by the shifter.)

Now you see how shifting works (beyond the chain and gears). You move shifter, shifter pulls the cable, cable pulls the derailleur to the next position, chain hits the shifting point on the gear, chain moves, you're on a new gear.

Shifting the other direction is pretty much the same except now you're not pulling the cable. The shifter let go of the cable, so the spring brings the derailleur back to smaller gear direction. This also happens by the step specified by the shifter mechanism.

Problem happens when you store your bike for a long time with derailleur in red arrow positions. Then you're constantly pulling the cable, fighting the force of the tension. A few hours or a few days in this position is fine. However, if it stays in that higher tension position for a long time (a few months) the cable gets stretched out.

Of course you can adjust the cable for smoother shifting, but when the cable is stretched out too much you need to get new cables. Other types of bicycles are a bit better, but for road bikes replacing cable is not really a simple job (it involves unwrapping bar tape, replacing cable and housing, re-routing the housing, putting the bar tape back on, and adjusting derailleurs).

So, move your shifter toward the green arrow directions during the storage.
If not, you may end up getting new shifting cables in the spring.