Corrosive sweat and front derailler
 

My front derailler has locked up and wont shift, My bike is 3 years old and I hadnt used it much until this year. I was told at a recent ride that I have corrosive sweat I guess kinda like the aliens in the movies where their blood is like acid. Anyway does it matter which derailler I replace my current one with? Will I have this issue with all deraillers? Will any derailler work with my Shimano 105 controllers, Is my bike destined to become a pile of rust?:speedy:

You haven't said what kind of 105 derailluer you have, double, triple, 9-speed, 10-speed, or what?
Are you sure the derailleur is the problem? Flip the small shift lever several times and then disconect the cable from the derailleur. If you can move the derailleur by hand toward the big ring then the derailleur is not the problem.
My sweat is very corrosive too but it's never stopped a derailleur.

Al

If you have corrosive sweat rinse your bike well after a ride when you pour sweat.

More details needed about your drivetrain before we can advise on which derailleurs will work.

How many chainrings? What is the tooth count of the small ring and large ring? 8-9-10 speed?

+1, never seen a derailleur fail from sweat. Check the cable, try to move it by hand.

Its a double, 10 speed. disconnected the cable and you can force it to go from the large ring to the small ring, but it will change from the small to the large ok.

There were bike mechanics at the cycle North Carolina event this past weekend and those guys told me I need a new derailler. If thats the case I'd prefer to repace it myself if possible. They said I could try and soak it to loosen it up but they werent confident that would work.

Rinse it off with water and then lube it. Work the lube in and see if that cures it.