Montreux Convention Regarding the Regime of the Straits?
It’s just another treaty. Russia don’t care about treaties.
http://en.wikisource.org/wiki/Ukraine._Memorandum_on_Security_Assurances
So why should Turkey bother about a far older treaty?
The Russian army looks impressive but is distributed over the largest country of the world. Turkey has quite a lot of tanks.
http://en.wikipedia.org/wiki/Modern_equipment_of_the_Turkish_Land_Forces
The Turkish Navy has 14 German submarines. That doesn’t looks nice for the Russian Black Sea Fleet.