> Since we've got a bunch of awesome gearheads commenting, can someone tell me why manual transmission is so easy to stall out? Particularly between say 1st and 2nd (...)

It's not easy, only if use it wrong. It's easy to stall going from neutral to 1st if you don't apply enough gas (for instance, if you're on a slope, or the car is loaded), but it will only stall from 1st to 2nd if you're trying to do it from too low RPM (in this case the engine may take a while to stall completely, you can still avoid it by unclutching), or if you work the clutch too fast (the engine stalls right away).

You might look at what RPM you are shifting from 1->2. As the other poster said, 1->2 stalls are uncommon because the vehicle is in motion and the power from the forward inertia coming up the drive train into the engine is frequently enough to spin the motor, even if its shut off. However, if you upshift too soon, the engine with the 2nd gear ratios will be spun too slowly for the engine to pull itself out, and will instead drag the car to a stop.

I agree with the others, you might be shifting too early and so the RPM will be too low for 2nd. Did you have trouble at higher RPM to shift into 2nd, like the gear shift would not move it, so you started trying to do so sooner? If so it may be that you were trying to shift too quickly (the actual action of shifting). It's okay to push the clutch in, go into N briefly, and let the RPM drop a bit before shifting into second. So say you start the shift at 3500RPM, maybe let it drop to 2700, every car is different though. A mechanical explanation might be that your throw-out bearing is shot, but I think you would hear or feel it if it was that bad.

The only time I have stalled out is when I am pulling away in first and let the clutch come up to fast. If you are stalling your engine going from 1st to 2nd you are doing something wrong, since the wheels are moving at that point. Even if you let the clutch come up too fast the engine won't stall because the wheels will keep turning it. It might shudder and definitely not like the low RPM's, but it shouldn't stall.

With a manual all there is between the engine is the clutch and the transmission. When the clutch is engaged your engine to your wheels is a single straight line (with some gears in between, but lets ignore those for now). If your engine has a lot of power it will simply turn the wheels, however in most cases the engine is just simply not strong enough to break the friction of the tires agains the ground, especially in lower RPM's.

When you slowly let the clutch up, what you are doing is having the engine turn faster than the pipe connected to the wheels, by using some friction material you transfer SOME of the power from the engine to the pipe connected to the wheels, as you continue rolling eventually the pipe connected to the wheels catches up and spins at the same speed as the engine (once again, ignore gearing), at that point you can let the clutch up entirely (thereby basically connecting it directly).

When you go from first to second, you use RPM matching to have the engine spin at the same speed as the pipe on the other end. When the RPM's match, you let the clutch up and from there you can start providing more power by pushing the gas pedal.

See more about clutch construction here: http://en.wikipedia.org/wiki/Clutch

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In most automatics there is a device called a torque converter that takes care of the friction part of the clutch for you. Interestingly enough it does this using fluid rather than friction material. There are fins on both sides of the torque converter, the two sides can freely spin. One side is connected to the engine, the other side is connected to the gear box. As you press the gas pedal, one side forces fluid through a series of fins, this whips the fluid into motion, this fluid is then forced through another series of fins on the other half. Because of the pressure difference in the fluid it will eventually have enough power to start forcing the other side (attached to the gear box and the wheels) to start moving. At some point the engine side is spinning just as fast as the wheel side, at that point most torque converters will actually lock. Now the torque convertor is directly connecting the engine to the transmission to the wheels.

When it switches gears, it disengages the torque converter lock, lowers the engine RPM's (even if you keep pressing the gas, it will use the computer to inject less gas temporarily), switch gears in the gear box, let the torque converter do it's thing, and once RPM's match closely re-engage the torque convertor lock.

See: http://en.wikipedia.org/wiki/Torque_converter

Ack, yes, you're right, I meant starting up, rather than from 1st to 2nd. I've driven a manual exactly twice roughly 15 years ago when I was getting my license; it was more of an abstract question regarding engine workings than a specific question about how to avoid stalling :)