# Front derailleur mod to permit MTB FD with STI road shift levers



## InertiaMan (Apr 16, 2004)

I thought some touring/bikepacking folks might be interested in a recent post of mine in the Shimano forum:

http://forums.mtbr.com/shimano/successful-front-der-mod-mtb-front-der-w-sti-road-levers-933644.html


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## ChristianCoté (Jul 13, 2014)

You know, Shimano does offer a full touring crankset that's compatible with standard mountain bike builds and parts. They don't market it in North America for reasons that are completely beyond me, but some of our manufacturers do use bits and pieces of them. Surly, for example, uses cranksets derived from these groupsets on their standard Trolls and Ogres.

Here's their Deore XT trekking line, from the EU site. I have most of this groupset on delivery right now. Even though this sort of stuff flies straight in the face of the direction mountain biking has been moving in for a while, I really do think that it's a very good choice for people who want to have a truly multi-purpose mountain bike.

Edit: ****, I'm sorry, for some reason this thread just whooshed over my head. I guess I was thinking about something else and tangentially related the two. Interesting solution you found there.


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## InertiaMan (Apr 16, 2004)

As you apparently realized after first posting, the trekking line doesn't solve the road shifter problem.

BTW, I've owned a "trekking" version of the XT cranks, and they are the same as normal XT with three exceptions:
1 - larger chainrings (usually 26/36/48)
2 - chainguard
3 - wider Q factor (driveside arm is spaced further out to clear the chainguard).

Shimano unfortunately treats all trekking bikes as flat bar bikes. But some of us want drop bar bikes with STI shifting and gearing sufficient to pedal 100 pound loaded bikes over 16,000' passes on gravel roads.

And before someone else points it out, I will admit that if I'm truly accurate, there is a single Shimano solution: Di2. If you're willing to go electronic, you can run 11 speed hydraulic road shifters/levers with the soon to be available XTR front and rear derailleurs. 

But if I can avoid it, I'd rather not use a drivetrain that costs more than the combined annual incomes of some of the villages I ride through!


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## NickandBruce (Sep 18, 2014)

Another option is to wait a couple months and pick up a set of Gevenalle integrated shifters. Word is they're working on adapting the new Microshift 10sp mountain barends to work on their levers so you'll be able to get good shifting from your shimano mountain der front and rear.


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## Saddle Up (Jan 30, 2008)

I ran 9 speed Tiagra and Deore without any problems, I wasn't aware that they were not supposed to work well together. Is this a 10 speed issue?


Surly Troll by SaddleUpBike, on Flickr


Surly Troll by SaddleUpBike, on Flickr


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## SimpleJon (Mar 28, 2011)

I've used my CX bike touring - I normally run it as a roadie with Ultegra 6703 52/39/30 crank, FD, STI's with an 11/25 cassette and a 6700 RD.
The RD does not like anything over 28T max rear sprocket size (I tried) my work around was to use an 11/36 10 speed XT cassette and an RD-M772 9 Speed long cage, this worked perfectly with the the front all 6703.
I've also seen an MTB set up with 105 STI's on drops an 48/36/26 LX 10 speed crank and FD-R5603 (which is designed for a 50/39/30) The guy whose bike it was said it shifted as well as when installed on an all 105 road bike - I can't vouch for that though I never tried it out


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## pimpbot (Dec 31, 2003)

Not sure exactly what you are all getting at, but it seems 9 and 10 speed up front is so close it works fine. I'm running a 9 speed FD wtih 9 speed shifters on 10 speed XT triple cranks. Works fine. IIRC, the only difference is that 10 speed chainrings are spaced like 0.2mm closer together.... like, a hair closer. 

On my 29er FS bike, I'm running the 10 speed triple with 22/30/42 tooth rings, but I replaced the 22t with an Action Tec 20t. I got a lot of steep hills around where I live.


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## InertiaMan (Apr 16, 2004)

pimpbot said:


> Not sure exactly what you are all getting at, but it seems 9 and 10 speed up front is so close it works fine.


My post is about using ROAD shifters with MOUNTAIN front derailleurs, a combo which is definitely not in the "so close it works" category.

I totally agree that the mountain FD/cranks/chainrings are largely insensitive to mismatching 9sp and 10sp. Did it myself often in the past, even with an Actiontec 20T like you.

FWIW, you might want to consider moving to 10 speed cassette/shifter/chain/RD. I held out for years on 9 speed, and initially wasn't that enthused when I moved to 10 speed . . . until I began riding it. The 36T cog is sufficient to avoid 20t chainrings, and the clutch rear derailleurs are a freaking godsend, one of those things that you don't know you need until you use it. A given the stupidly cheap prices for SLX and XT on some UK sites, making the move is totally affordable. FYI.


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## InertiaMan (Apr 16, 2004)

SimpleJon said:


> The RD does not like anything over 28T max rear sprocket size (I tried) my work around was to use an 11/36 10 speed XT cassette and an RD-M772 9 Speed long cage, this worked perfectly with the the front all 6703.


Yep, for all 9 speed and under, Shimano MTB rear ders have identical cable pull to the road rear der, so they interchange perfectly, and are the ideal option for wide range cassettes,



SimpleJon said:


> I've also seen an MTB set up with 105 STI's on drops an 48/36/26 LX 10 speed crank and FD-R5603 (which is designed for a 50/39/30) The guy whose bike it was said it shifted as well as when installed on an all 105 road bike - I can't vouch for that though I never tried it out


That's roughly equivalent to what I'm running on my touring rig. It does work -- the combo of road shifter and road FD ensures proper shift proportions -- but my personal experience is that the shifting is compromised because (a) the chainline is 50mm instead of 45mm, and (b) the FD cage shaping & radius isn't well matched to the MTB chainrings.

One can purchase an offset FD clamp from Santana which moves the FD 5mm outboard to solve issue (a), but issue (b) remains.

When you move to smaller ring sets (like 22/32/42) the road FD shifting suffers even more. That, and the fact the bike I was building had top pull FD routing, led me to the effort of FD mod in my post.


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## InertiaMan (Apr 16, 2004)

Saddle Up said:


> I ran 9 speed Tiagra and Deore without any problems, I wasn't aware that they were not supposed to work well together. Is this a 10 speed issue?


It's the same issue for 9 speed or 10 speed. I'm surprised you had reasonable function mixing Tiagra and Deore on a triple. Was the cable anchored in the stock location? Or opposite side of the bolt maybe??


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## Saddle Up (Jan 30, 2008)

I"m not sure now that you ask. Looks like the normal location. Can you tell fom the photo?


Surly Troll by SaddleUpBike, on Flickr

The guy that tuned my bike is a career mechanic, been at it for over 20 years. I vaguely remember him bending and shaping the derailleur oh so slightly with a pair of pliers, I just assumed at the time that it was normal practise.


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