Shimano Front Derailers

I have a query about Shimano front derailers if anyone can help. I'm talking road derailers and feathering. Do all road derailers (Ultegra is my example) allow themselves to be compatible for two and three rings on the front?

Does the feathering function of the derailer in the normal two chainring mode become the means of shifting to the middle ring in the three chainring mode?

I hope I'm asking this question clearly!

 

First question:

Dura Ace 7800, 7803-No

Ultegra 6600, 6603-No

105 6500-Yes

Tiagra 4400-Yes

Sora 3300, 3304 No

I can speek for Ultegra ST-6510, Yes

7700- I don't think so

5500-Pretty sure yes

Second question-No

 

Thanks heaps. So is a three ring front shifter indexed the same as the rear shifter? How does that work?

 

Best to read the Insructions from Shimano. http://www.shimano.com.au/publish/c...er_support/service_diagrams/Road_SI_2006.html Double and Triple FDs havd a different size cage 16t, 11t, and the shifter has a different amount of cable pull and therefore lift. Triple with triple and double with double, the trim function just allows cross chaining in the smaller ring on a double and middle ring on a triple.

The Ultegra rear, 10 with 10, 9 with 9, 8 with 8. (Yes 8 rear Ultegra does exist)

 

After rereading your ? I realize you were talking FDs. I was talking brifters.

gclakr8 is correct, all FDs are double/triple specific.

Also, I don't understand the ? in your second post. Front is front, rear is rear.