Cyclocross - Mixing Mountain (XTR) & Road (DA)

I want lower gears. My plan is: DA cassette, DA rear derailleur, DA shifters with XTR cranks and an XTR front derailleur. Anybody know if this will work? If not, any suggesting to accomplish the same thing? Thanks-dhk

Why the XTR up front, and how low are you talking about? XTR cranks are triple, and unless you are setting up a touring or MTB, triples have no real place on a 'cross bike. (not to sound elitist, but this sounds like a rather uncommon setup that you most likely will never find on a race bike).

For cross, the tiny ring on a MTB crankset would be useless since it will always be faster to run than to spin the granny gear, however I think the middle ring (32t) and big ring (44t) would provide a nice gear recuction compared to the usual 36-48 that comes stock on a cross setup, without sacrificing too much from the top end. This would prove especially useful on muddy or snowy courses.

I would personally leave the front alone and swap in a mountain cassette and rear derailleur because this would be simpler to do, would provide a smilar gear reduction and would cost much less. If we're talking new parts at MSRP, that's $460 for XTR crank vs $310 for XTR Rear der + cassette.

If we're talking 9 speed here, this will work...if your shifters are 10spd, then you're stuck with DA in the rear

DA Shifters won't work well with an XTR front derailleur. Road front shifters and mountain bike front mech's just don't mix right (something to do with the leverage each is designed for I think). I've tried running an XTR front with a 105 shifter on my Monk (which is top pull) and it was horrible. I put on an old school Exage mountain bike front derailleur it it works better but still not well and took much trial and error to get to the point of being usable. On the rear the combo will be fine (I run 105/XT).

You are right... this is a road bike. I was looking to the cyclecross forum as a source of expertise about low, low gears.

STI and mountain shifters do NOT pull the same amount of cable for the front derailleur.

read under "front indexing"

http://www.ctc.org.uk/DesktopDefault.aspx?TabID=%204068

For cross, the tiny ring on a MTB crankset would be useless since it will always be faster to run than to spin the granny gear, however I think the middle ring (32t) and big ring (44t) would provide a nice gear recuction compared to the usual 36-48 that comes stock on a cross setup, without sacrificing too much from the top end. This would prove especially useful on muddy or snowy courses.

I would personally leave the front alone and swap in a mountain cassette and rear derailleur because this would be simpler to do, would provide a smilar gear reduction and would cost much less. If we're talking new parts at MSRP, that's $460 for XTR crank vs $310 for XTR Rear der + cassette.

If we're talking 9 speed here, this will work...if your shifters are 10spd, then you're stuck with DA in the rear

I have a kind of "odd sized" triple in the front 48-38-28 and I find that even with a 12-26 cassette, I get can get pretty low without spinning too much. The old cassette was an 11-30. The 30 was too low and the 11 was too high for off-road (at least for me) so I got rid of both extreme ends and had less drop off between the existing gears. The LBS mechanic (who also races cyclocross) suggested the cassette change instead of changing out the chainrings.

T.