Bicycle Mechanics - Shimano 105 triple 52 teeth compatible?

Had a look at the different options for exchanging my 105 triple derailleur. I have a 9 speed that are 4-5 years old, and have a 52 teeth ring in front.

I found two 105 triple shifters from Shimano, but the problem was that one of them only supported 50 teeth and the other only supported different shifters from mine.

Any suggestions?

Shimano 105 cranks usually come with 52 or 53t chainrings, standard. I'm curious what front derailer you're looking at that officially only supports 50t chainring max.
However, even if the FD is a "compact-specific" and rated to 50t max, it should work fine with 52t.
The two main factors limiting what chainrings can be used with what FD are chainring size (depending on the radius and subsequent curvature of the FD cage) and gap between large and small chainrings. Estimates from the manufacturer tend to be conservative for both of these numbers.

This is the one compatible with my shifters: http://www.chainreactioncycles.com/Models.aspx?ModelID=13623

Both this site and the Shimano site says 50t

There is also a 5703 that supports more than 50t, but I don't think this is compatible with my shifters.

FD-5603 should work just fine with a 52T top ring. Like TallRider said, the tooth ratings are often pretty conservative.

The reason it specifies 50T is that the 105 triple from the same group, FC-5603, came with 50-39-30 chainrings.

OK - great! Then I have to more questions:

* Will this 5603 be compatible with my "Shimano Flightdeck" shifters? I don't know the model number of the shifters
* If I decide to change the middle chainring - do I have to unmount the complete crank, or can I just loosen it and take it off?

1. Yes

2. You should be able to take it off without pulling the crank, it's just a lot easier if you do.

OK - thx for superquick reply!