I am having problems with my Shimano front derailleur

Way too many possibilities, especially with a description of "won't work." If the bike is brand new then you should be taking it back to the place you bought it.

I’m happy to help further over the phone at https://www.6ya.com/expert/donald_f2ed37026a3ac881

There is typically not a single cause or solution to a specific shifting problem. The most common way to resolve your problem is to let off a bit on pedal pressure as you shift. The derailleur has to move the chain sideways off the teeth, and that is more difficult when the chain is under high pressure.

I’m happy to help further over the phone at https://www.6ya.com/expert/donald_f2ed37026a3ac881

Not a problem that can be diagnosed without eyes and hands on the bike. Post a clear video, or better - take to a bike shop or bike co-op.

I’m happy to help further over the phone at https://www.6ya.com/expert/donald_f2ed37026a3ac881

You will need to raise the back wheel to perform these adjustments... so that you can activate the pedals and oberve closely the functioning, as you adjust....

On the tube mounting: The derailleur needs to just clear the teeth of the front chain wheels, as it moves from one to the other. It needs to be square with the chain wheels.

The other adjustments are limiting in nature. You need the derailleur to not move the chain off of the outside of either front chain wheel. as you get closer, move the rear derailleur to extremes and then shift the front derailleur, slow and fast..... Limit is correct when you can move the derailleur so as to not ride on the chain, but not throw the chain off the wheels.

Sometimes, guys turn the front derailleur, slightly so that the last portion of the derailleur body gives the chain a little boost to the bigger gear...This is just a very small amount. Sometimes it just works better that way.

No, it is a front derailleur, and must be able to accomodate 3 front chainrings. Where did you get the derailleur, from what bike? They are not universal fit. A lot depends on your shifter to work and the size of your frame.

There are a couple of possible problems. You can try backing off the cable tension a little bit at the shifter and running back and forth through the gears adjusting as you go till it hits 2nd coming down.You can also try backing off the High limit screw on the derailleur. This will allow the shift to start a little farther from the bike hopefully hit 2nd. Hope this helps.

Yeah you will run into that at some bike shops. When they see older components like that, they often refuse to adjust them for fear of breakage and liability. Try a different bike shop if you can, or if you are confident in your mechanical abilities, try it yourself, instructions here:
http://www.ehow.com/how_6086607_adjust-shimano-rear-derailleur.html

Good luck.

There are several things that could be wrong. You could have thrown your chain (you couldn't ride at all if so). The bike could have been crashed and the derailleur bent. The cable might have slipped where it bolts to the derailleur. Or the cable or shifter could need maintenance, too. It is most likely one of the above. If it is only the adjustment, there are two stop screws on the derailleur that can be adjusted.

My best advice for you is to either find a bicycle repair manual at a local bookstore or your library that can show you some of the detail. Or just let your local bike shop do the repair.

It sounds like you could have two different problems. Your derailleur has become contaminated or your shifter may need to be lubed. Either way, the likely solution is the same. The best solution to get the derailleur operating again is to spray it with GT-85 or PB blaster and manually move in back and furth until it is working again. The same goes for the 105 shifter, spray GT-85 inside the shifter by compressing the brake lever and spraying towards the head of the shift cable. This will solve a non-functioning shifter many times.

The only other problem that fits is the limit screws could be wrong or the deraileur is in the wrong position. This would not be the case unless someone adjusted your derailleur before the ride you started have that problem. Or if the derailleur has moved. Both of which require the derailleur to be fully readjusted.

Hope this helps. Thank you

Go to Parktool.com it's real easy. good luck