Touring - Shimano Road Shifter with Shimano Mtn Front Der?

A friend is having trouble with the following setup on a surly LHT:

- sora shifter
- deore front der
- 52/42/32 chainrings

Can you use a shimano road shifter with a shimano mtn front der? Any other obvious problems with this combo of components?

She needs a road derailleur. Mtb front derailleurs have slightly diff pull rates and do not work too well with SIS.

Fixer...
Is that true with bar cons as well?

Barcons should be fine. I use 8spd Ultegra barcons and xt front derailleur w/ a 46 max chainring and it works quite well. I think the issue lies w/ the Deore derailleur on a 52 chainring. I'm not exactly sure what is the max chainring that can be used w/ the Deore. My first cross bike used a mountain front derailleur combined w/ a RSX road brake/shifter and it worked but it was a pain to adjust.

I posted a similar thread once, which earned some good answers:

http://www.bikeforums.net/showthread.php?t=186378

If your largest chain ring is beyond the capacity of the MTN derailleur it's going to work very poorly because you'll have to mount the derailleur too high on the seat tube. Other wise (other than the capacity/ max size issues) derailleurs are robots, they do as they are told by the shifters. It's the shifters and the chainring/cassette spacing that have to be in perfect synchronization.

derailleurs are robots, they do as they are told by the shifters. It's the shifters and the chainring/cassette spacing that have to be in perfect synchronization.

Actually its the other way around. "MTB" and "road" chainrings have the same spacing. "MTB" and "road" shifters pull different amounts of cable to move between those same spacings, because the two kinds of front derailleurs are designed differently. Its all in the thread I linked.

Also, for loaded touring a 32 tooth granny is way to big.

How low can your granny go? :D