# Of cranks and drivetrains.



## bakerjw (Oct 8, 2014)

Well, we're a couple of months off from getting our tandem frame so I have time to put some research time into component options. Now it is cranks and drivetrain.

I wondered what other MTB tandem riders have for crank sets and drive trains (i.e. 2x or 3x). Cranks seem to be a sticking point right now.

Steve, my normal bikepacking bike has a Shimano XTR 2x10 drivetrain with front sprockets being 24/40 and rear 11-36. When I graph out the ratios, there is broad separation between 24 and 40 ranges while still having close enough on the back sprocket to maintian a target cadence. What I mean by that is when I am normally climbing a long grade, it is nice to be able to kick up or down a gear to get where your legs and joints are happy. Whitefish Divide always comes to mind when I mention it.

On the high end (40/11), at 90 cadence, I go 27mph. On the bottom end(24/36), my body gives out before the bike does. It looks like a good starting place to me.

Thoughts? Comments? Suggestions?


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## mactweek (Oct 3, 2011)

I used to use a 3x9 crank, 44-32 22 x 11-34 , but since we never really take the tandem on the road, I switched it over to 2x10 with 22-34 x 11-36. It gives us good gears for off road and it was parts I already had. It shifts much better also.
Your 24-40 should work well, it should work with a 2x front derailleur which shifts much better than any 3x ever did.


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## Okayfine (Sep 7, 2010)

All depends on where you're riding, and what your stoker wants to put up with (regarding low range and topping out of gears).

We run 3x9 because that's what came with the original bike we bought, and 11x34 out back. On our normal trails, we'll use every single gear, and (briefly) need a bigger big ring.


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## PMK (Oct 12, 2004)

Currently, there are many teams running various setups. We still run a 3x9 with us using most everygear, depending upon where we ride, but no doubt some are more used than others.

Do not choose your gearing based on what you run. Plan on, if possible gearing super low to pretty tall if possible. You may find that unless your stoker is as strong or stronger than you, there may be times when you are the one turning the majority of the pedals.

If I were building a new machine, dedicated to bikepacking, my choice would be a Rohloff on the back with a 2x up front. 

Not sure where you plan to ride, but from experience, we put in many long training rides in prep for CFITT several years ago. Debris in the rear mech was reasonably common riding those less ridden / not groomed trails. For simplicity and strength I ran DT hubs. With a very easy mod of removing the O ring, it allowed the cassette / freehub to be pulled away from the hub body to remove debris or a jammed chain in the spokes.

Your crank choice may also be a driving factor in how you build the drivetrain around the cranks.


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