The first mistake that many unknowingly make is to forcefully release the lockbar. This only causes more problems as you are "sheering" the two surfaces causing deformation of the surfaces.
When the lock becomes stuck place the knifes edge on a cutting board, while holding the handle use your free hand to apply downward pressure in the stop pin/pivot area. This will on a very small scale create a gap between the lock bar and lock face allowing you to easily release the lock. Again go not pry the lock, it can induce further wear and only make the problem worse.
A loose pivot causing side to side play when the blade is open can also cause a sticky lock and excessive lock wear. Even small amounts of play can do it, check by holding the knife open and liner facing up, move the blade side to side and if your lock bar moves you need adjustment. When looking at the knife/lock from this possition you can also check the fit. The contact point of the lock bar should be the upper right corner of the bar and only about 1/16in square of that corner makes actual contact.
Too much oil, too much pivot oil spilling over onto the locking surfaces can also cause a sticky lock. Those that use oil to fix a sticky lock I don't know how your doing it.......
The pencil trick works and seems to last if not completely fix the problem on most. If its really bad ask for a replacement as it will never get better, also if you pryed it too hard it caused damage that will continue to cause problems.
If you must, take the knife apart and clean the face of the lock bar, I have had to do this before.
Some of the best frame locks like XM18, ZT0300, CRK, all have top notch fit and function. My personal experience with the ZT made me realize what a really well made and fitted frame lock should be like. Not only was it assisted but I put it through some good use and hard openings that would have froze a normal lock. When I sold it over a year later the lock had moved less than a 1/16in and was still as smooth as the day I got it.
Keep the lock surfaces clean, use the pencil trick, and check for play. If its not working better after that and break-in (about 200 cycles) then it might not get better.
One more very important thing to remember, during break-in open the knife easy. This is usually were most problems start.
OldDude1, excellent post!
Thats the worse possible thing you can do to a framelock (especially Ti), as it will cause deformations on the lock bar face and can negatively effect your lockup and severly speed up lock wear so that it locks up closer and closer to the opposite liner.
