Shimano 105 and Dura Ace interchangeable?

[Pilsbury]

I have a 105 - equiped road bike, 10 speed, compact chainrings, bought 2009.
The front derailleur cage is gradually bending out of shape already - very dissapointing - and I'm tempted to replace it with something better. Would a 10 speed Dura Ace 7800 be a straight swap? Or would I need new shifters too?

Thanks Bike Brains.

[Polar Bear]

Straight swap.

However, I'd seriously consider taking it back for replacement.

[gonzo]

Yup, pull ratios the same within product range of each manufacturer.

How's it bent?

[Simon Galgut]

Dura Ace 7800 is OK, but not 7900. 7900 brake calipers and front mech use different cable pulls to every other Shimano range. 

[Hot Flatus]

Post a photo

[bloomers100]

Mine bent too when the chain leapt off the big ring. Squeezed it back in. I was surprised at how flimsy it is. Mine has a slight crack appearing in it too.

[Pilsbury]

Straight swap.

However, I'd seriously consider taking it back for replacement.

Thanks for the quick replies!
I think you are right - I should take it back to the shop. However, I don't think it's a manufacturing fault, just cheap materials / design. When you shift down, the outside of the cage hits the chain with quite a wack. Over time, the cage has been opened up as a result, increasing the gap. It's easy enough to bend back into shape, but the metal is sure to get progressively weaker.

[gene hunt]

If the gears are set right it should not hit the chain that hard, front mech can and will last a very long time in my experence plus having built a lot of bikes.

[MSeries]

My front mechs last many many years, like 20 or so, they get gummed up with crap and seize up before they break. Though I don't use STi, click-BANG!

[gonzo]

Silly question, but are you using a band on front dérailleur and if so, is it possible that it's simply twisted around?