becnal

On a fully loaded touring bike going up hill, you're gonna want the option of having that granny ring, believe you me.

nun

A mountain double and an 11/34 or 11/36 cassette will work for loaded touring in any terrain. Compact doubles and 12/25 ish cassettes are probably best used with light touring loads.

I find doubles simpler to use than triples, but with any gearing you should try to get your most used gears with the least amount of chain angle.

cyccommute 

Sorry but I don't agree. Whether or not a mountain double...or a road double...works depends on the person, not the terrain. For me, I prefer to have a nice wide range that gives me the ability to climb comfortably and descend fast without running out of gears too quickly on either end. Others may have different tastes.

I also find compact doubles and mountain doubles to have really lousy gear patterns. There's no smooth transition between the two rings. If, for example, you were using the 38/24 with an 11-36 cassette and you were in a 42" gear in the front (38/24) and had to shift to the inner ring, you have to shift up on the rear 4 gears to get a similar gear. If you just dumped to the inner ring, you'd go from a 42" gear to a 27" gear. That kind of jump is going to require a huge increase in rpm to keep up. Either way it's futzy. There are more intermediate steps with a triple and fewer double (or quintuple) shifts.

fietsbob

White Industries variable bolt circle crankset merits consideration for a double .. big ring has 5 slots.

so smaller inner ring is at the bottom, bigger, further up.. advantage is wide choices of gearing..

somewhat like old TA, but not it's 11 little bolts and older, 50's, design limiting shifter options.

pacificcyclist

The bike shop guy is correct, but it only applies to a road trekking crank (Sugino SD600 46/36/26) OR 48/36/24 (110/74BCD). If you are comparing against a mountain triple crank, then you do not have as low a gear as you would with 42/32/22 or 42/32/20, with the latter giving up a low 16-17" gear inches.

Road triple crank; you will loose about 2 gear inches on the top end because of the difference between 48/46 big ring and then 42/40 big ring on the touring double. Not a big deal if you're touring.

Mountain triple crank; you will loose about 1 or 2 low gear inches. 24T on your double (smallest you can fit) as opposed to 22T or 20T on your mountain triple crank.

So in a way, a touring double will give you a comfortable high, medium and low gear from 19" to 100" if you're going with a 42/26 or 42/24 or 40/24 which is a common setup.

First of all, I would not go with a Shimano XT 10 speed setup. The 10 speed XT rear derailleur is setup to work with 10 speed mountain shifters, not 10 speed STI brifters you want to get it to work. You will need a 9 speed rear derailleur like a Deore or a LX with a longer than usual B screw. It seemed my older 9 speed LX derailleur does not need the long B screw as it works beautifully with a 11-36 SLX cassette. For the front, you will only need a Tiagra front double derailleur (10 speed version) as this version will work with the modified 110/74BCD triple crank converted to a double. MAKE SURE you get a good set of 110 BCD ring that's as round and flat as possible or you'll have a slight run out at the extreme 40T/42T to 11T rear or 40T/42T to 36T rear. There is only so much latitude you can get with the Tiagra and this derailleur provides the most widest throw for this setup and works great with a Shimano Tiagra/105 and Ultregra 10 speed brifter.

Incidentally, I do have this setup on my Masi touring bike which was a cross bike with a compact crankset and it works great and you do have to do some double shifting to get some gears, but it only depends on your cadence too. How many gears are you going to use on tour with your cadence? All 20 gears? I highly doubt it. Probably about 8 gears if not less that you'll be using so this double shifting concern is moot. In fact, last year tour, I really enjoyed having a touring double. People with Salsa Vaya 2 have a touring double of 40T/28T and the people I met this year almost all use touring doubles because of the 10 speed cassette. Even the folks pair of Pathlesspedaled who toured with a pair of Bromptons before are now touring with a touring double. No problems. A triple setup is not really necessary at all for touring because most of the time, you are using the 2 inner rings anyhow. But some people need a massive ego boost just to have a 46 or 48T to go bombing down a hill with show and style. If that's you, stick with a triple. If you're practical, the a touring double will do you just fine.

Rob_E

It seems like you can get the same range out of a double as a triple, unless I'm missing something. You just set up a double with the same inner and outer rings of the triple, and drop the middle ring. What you lose is the amount of options in the middle. If you like to find tune your gearing for a particular cadence, or if you like to have steady increments to shift through, a triple will get you there. If you don't care as much and just want to make sure you have a low gear for hills and a high gear for speed with a few options in between, a double will do the trick.

pacificcyclist

I prefer Jan Heine's Rene Herse double crankset with 3 bolts that is being sold through Compass cycles. Some of the best cranks and flattest rings that run so true you won't have run outs when shifting at the extreme! I have a pair of Sugino Super Maxy cranks and thankfully for old school good quality forged cranks, it runs pretty true with little run out.

cplager

I've got a 48/38/22 triple. 38 to 22 is already a big jump. 48 to 22 isn't really practical. So, technically speaking, you're right. Practically, no. A double just won't give you what a triple does.

pacificcyclist

I used to worry about this, but I did some calculations and I found that the best combo would be a 40T/26T or 40T/24T for which you will only loose about 2 top gear inches against a stock Sugino SD 600 46/36/26T. You won't notice the difference except during the transition between medium middle gear inches to high low gear inches where you would need to perform 1 shift on the front and 2 shifts on the rear totaling 3 at least in my case. I also have a triple on my Trek carbon bike and if I go down to my lowest 30" gear inches, I have to do the same shifts to get 55" after a steep climb anyhow, but with my touring double, I only do 2 shifts because I planned it that way. Either way, the shifts are going to be different for different people.

I also run a slighty shorter crankset (165mm as opposed to my usual 170mm) so I can concentrate on spinning seated rather than attack retrench method I do with my road bike during steep hill climbs.

2 bikes with 2 different purpose. Carbon road bike for light touring and steel bike with a touring double and a mountain rear cassette for loaded touring.

LeeG

My around town bike has a 30/44 with 12-28 8spd cassette. I have a 13-34 8spd available for touring that gives five nicely spaced gears between 10mph-17mph riding. I've come to the conclusion having gears above 93" for touring is a waste of space. The only way I'll be cruising above 20mph is down hill.

bobotech

The STI or any indexed road shifters don't care what kind of crankset you have on there, all they want is a front derailleur with the proper cable pull amount. Mountain bike shifters pull quite a bit more cable than road bike shifters so if you try to use a triple front road indexed STI shifter with a mountain bike front derailleur, it won't shift right if at all since one click of the shifter will barely be able to move the cage at all.

So it looks like to me all your bikes are setup with road front derailleurs using mountain bike cranksets which can work just fine if you know how to get it working right. You do have to be careful that sometimes the cages on road derailleurs are so much bigger than MTB derailleurs and have problems shifting small front chainrings.

I converted a mountain bike to use drop bars with STI shifters and had to put a bigger crankset on the bike so it would shift as smoothly as I expected.

Shimagnolo

Agreed. When I put an Ultegra FD on a crankset with a 48T large ring, the radius of the cage put the tail of the cage so far from the ring, that after using the shifter, I had to reach down and grab a handful of cable along the downtube and haul back on it to temporarily pull the cage even further to the right to actually make the chain climb onto the 48T ring.

Replacing the Ultegra FD with the Alpina-D solved the problem.

robble

I haven't heard anyone answer the specific question of 'why not go with a triple' unless the answer was there but I didn't recognize it in all the technical talk.

I have a triple and it came in handy when I went on a group ride mountain loop road. I was on a hybrid and everyone else was on road bikes with doubles. On the way up the roadies would be in their lowest gear and having to mash or even stand. I just dropped it down and spun easily while sitting. During less steep parts they would still be in low 1st gear and I'd be in gear 4 to match cadence and speed. On the way down the mountain I could just put it in high with a ~80-100 (guesstimate) cadence while doing 36mph downhill. I guestimate the cadence because at that speed I'm not taking the time to read my cadence display. I check top speed after slowing down.

The highest gear is high enough that I very seldom use it on the flats since I'd have to mash.

ksisler

+9 on the Gambler; If the OP can spot the cost, there is a lot of sense in doing it all inside and simple as he suggests.

Several good choices are available.

LeeG

So you can put one of these in the outer position!

djb

to the fellow asking this question-as you can see, we are a bunch of gearing nerds here, so what I hope you get out of all of this is the urge to use gear charts and perhaps compare the diff variations to what you know about your biking. If you havent toured at all, (and we still have no idea what sort of touring you are planning or have done) at least look at what bikes you have ridden and figure out the gearing (do a chart using these online things, like the sheldon one) so you can relate to all these opinions.

if you arent interested in the technical aspect of it, well, then at least take into account opinions from people who have toured in diff situations of load and terrain.

robble

Kind of hard to see but I have one of those on my triple.

Clipped_in

Demonstrating once again that honesty truly is the best policy.

KirkBeiser

Do you find cross-chaining to be an issue? I was running the numbers for a 24-40 and even though the ratios work I found it inevitable that I would be using the wrong half of the cassette frequently. I agree that 93+" is not needed but I would need to get to around 20" because the 25" that I currently have is inadequate (requiring the 24 or 26 on a double). I like the simplicity of a double but cross-chaining seems inevitable and with a 36 middle front ring I can ride almost directly in the middle gears most of the time.

pacificcyclist

I have no problems running this combo, because this combo happens to be similarly configured as a 53/39 in a higher road biking configuration or as a 50/34 cross biking scenario both of which do not offer a low 20" gear like a 40T/24T does with a 11-36SLX cassette. Notice a 16 tooth difference between 50/34 and 40/24 and a 14T difference on the 53/39T, but some strong riders put a 55T in place of a 53T making it a 16T difference. What people do not realize is that, all 40T/24T with a 10 speed 11-36SLX does is to gain 1 top gear and 1 low gear over a 2x9 system. If the OP is running a 9 speed, by all means run a triple.

For example on a 46-36-26T stock Sugino triple crankset on a 11-34 9 speed cassette, you get a high of 116.8" on 11 and 98.8" on 13 matched with a 46T, but with a 40T and 11T on the 11-36SLX, you get 97.3", but you also gain a 17.8" gear lower than a 11-34 on the 9 speed cassette. In this case, the SLX 10 speed double setup offers all the benefits of the triple, plus a much lower gear at the expense of 1 top 116.8" gear.

Doug64

This is not a problem. You do have to use a shorter bottom bracket. I use 103 mm bottom brackets (68 mm bottom bracket shell) to get a chainline of 45-46 mm with 44/32/22 Sugino DX 500 mountain bike cranks. Mountain bike cranks are designed for a 50 mm chainline. That means that the bottom bracket used on a road bike needs to be 8-10 mm shorter than for a road crank. This can vary and there is a process for figuring it all out. I use Shimano Tiagra front derailleurs (4503) which are a more forgiving derailleur than Ultegra. That is why most touring bikes with triples, even high end ones, came with Tiagra FD's. All our touring bikes run with Tiagra STI shifters (4503). I can adjust the front derailleur so there is no chain rub even when max cross chaining at both the high and low ends ( I don't cross chain on purpose). They really do shift nice!

If you could not adjust the Ultegra to a 48 tooth chainring, I suspect there was something else going on beside the fact that it was an Ultegra. I have used Sora FD's with 46 tooth chainrings and STI shifters without any trouble. However, I did shorten the BB to maintain ther proper chainline--It is all about chainline!

fietsbob

CX chainguards are for mostly 42,44t outers on road cranks... old stuff I got one sized for 50t

with that sized outer, and a 40 middle and a 24t low ring .. and a chain catcher inside that , i dont do overshifts..

discontinued a salsa 48 t ,, have a spare.. wave money to get my attention..

cplager

I consider a 20% loss in range significant. And with a triple, you can get a much tighter cassette with and still keep the low range. Some people will also complain that a 10 speed chain is weaker than a 9 speed chain (although I'm willing to believe that those complaints are over-blown).

If you're happy running what you're running, then you're golden. But I really don't understand what many people have against triple cranks, particularly here in touring.

Altbark

I don't think anyone has anything against a triple setup. The reality is that the leading edge of mountain bike technology is leaving the triple crankset behind for the double. The reason is quite simple. Doubles shift better, can provide a more useful set of ratios and are simpler to maintain. The question to be answered is not how many gear ratios you have available to you on your drivetrain but rather how may useful ratios do you have.

I pull a trailer with a Cannondale T1. It is a friction shifted 3X9. My bike tops out at around 95 GI's and bottoms out at around 18. If I was doing it again I would be running a friction shifted 2X9 setup topping out around 90-95 GI's and bottoming out at around 18. A fully loaded touring bike is not run like a road bike.

If I was the OP, I would be looking for the max and min gear inches desired and then build a 2x9 or 10 to suit. Anything over 90-95 GI's on a touring bike is rather pointless in my opinion and a nice low gear is almost always better then pushing the bike up a hill. Al

pacificcyclist

People aren't against it, but sometimes people do not have a choice with the newer 10 speed Tiagra cross bikes that are being sold. With double shifters, the only way to get low gears is to get a touring double. A stock 50/34 replaced with a 46/34T and a 11-36 rear gives you a nice 25" low gear. Replace the crankset with a 110/74BCD and the same cassette gives me a low 18" gear. For me, I really had no choice in the matter. It was a financial decision. The bike co-op had everything I needed and cost me $250 to do the whole thing with new and used parts plus labour. Then I realized other bikes in the shop are going through the same procedure too, so when the bike shop said to the OP that the double can serve the same purpose as the triple if you get the cassette right, the owner is correct.

Secondly, the range of cassette between a 11-34 9 speed and a 11-36 10 speed is actually the same for the first 6-7 cogs except with the 11-36, you get 32 and 36 instead of 30 and 34 on the 9 speed. While you do get easier gears across the range to ride on with a touring double, the difference I found is not all that noticeable. I can still keep up with my touring buddies with triples with one exception. My front derailleur does not jam when shifting from 24T to 40T, whereas theirs will occasionally do from granny to the big ring under stress. The benefit of double simplicity. Other than that, the chain on the 10 speed has to be a Shimano HG-X HG-74 and the pin is not re-usable unlike the SRAM 9 speed Power Link. The HG-74 is a mountain bike version and is supposed to be more durable compared to the same Ultegra 10 speed chain that is lighter and less durable.

Lastly, the benefit of a touring double is no chain tattoo for the ladies with the chain guard in place. That's their numero uno complaint. One lady I met last year on tour had her triple converted to a double and set the triple shifter to only shift double for just this one reason. Her front is a 40/24T and a 9 at the rear. The key to a good working touring double is to get useful ratios on the bike and all you need to figure out is just that 1 chain ring. 110BCD is easy to get rings in different sizes anyhow.