the desert fox

Hi Everyone,
i just saw the reverse set-up on a commuter bike. it has an XT rapidfire 3 speed trigger shifter and a 105 front derailer with 105 triple crank. if this set-up works, then the indexing on the XT shifter is the same as the indexing on the 105 front derailer is the same, right? so do you think this would work the other way around if i use XT front derailer with XT cranks and 105 dual lever? anyone had any first hand experience? by the way, this is a 3x9 speed set up
thanks in advance!

Al1943

The Shimano triple compatible road shifters have 4 main positions plus a trim position. So they don't work the same way as mountain type shifters. But some people seem to be able to make anything work.

Al

tellyho

I'm pretty sure road levers and mtn FDs are incompatible. But you could just buy a road FD for cheap to solve it.

JTGraphics

The can of worms has been opened most MB large chain rings are 44t and road bikes 53t so getting a road FD made for a 44t rings I'm not sure about so a road crank + FD may be needed for a smooth shifting drive train.
I'm sure you can get some work around for this but for 100% operation switching to all road up front may be best.
Not sure if ShiftMate makes something for your needs or how well they actually work.

Retro Grouch 

Maybe not. You may encounter a cable routing problem since most mountain bikes use top pull front derailleurs and all of the road derailleurs that I'm aware of are bottom pull. You man also encounter an issue with the arc of the derailleur not matching the chainrings very closely.

HillRider

Shiftmates work wonderfully but are only used to match REAR deraileurs, shifters and cassettes. There is no equivalent device for front shifting.

I tried to use a 105 8-speed front brifter with an older version LX crank and front derailleur and they wouldn't index properly. I wound up using a single barcon for the front shifter.

satanas

There actually *is* an FD Shiftmate now: https://jtekengineering.com/shiftmate_straight.htm

The Shimano MTB shifter works okay with the road FD as it pulls more cable than required. If you do the opposite the road lever will not pull enough cable, so the FD won't move far enough in or out, and that's if you had a triple lever; with a double lever you're SOL. (If you have a friction shifter - such as a barcon - all is well.)

joejack951

I would try this derailler: https://www.universalcycles.com/shopp...7&category=529

It's designed to work with smaller road rings so it has a good shot at working with a MTB crank. My current commuter has a MTB FD (Acera) shifting a 48/38/28 crankset and it works just fine.

Or just use a non-indexing shifter like others have suggested.

bkrownd

Not necessarily incompatible, but it depends on the individual components. My fun bike has a 105 brifter shifting a SRAM Xgen front derailleur over a 44/32/22 crankset. (the rear derailleur is still a 105) The trick is that when I'm on the middle chainring I have to adjust the derailleur cable trim (tension) nut as I move from the largest to the smallest cogs. (i.e. adjust it once right around the middle of the cassette) It's easy to do because the nut is right there between thumb and forefinger on the brifter. Otherwise it works normally so far, and index shifts between the chainrings with no problem.