geachyguy

I am looking for a crankset for a bike I am building for a ride from Minneapolis to South America. I am debating between the shimano LX and XT cranksets - can anyone tell me the differences between these? The LX are much cheaper (~$90 vs ~$200).
Thanks!

ocho

I don't know the differences between them but can pass along my observations. I toured with a friend last week, he using the LX and me using my XT crank. He had definite problems with creaking and squeaking which are admitted issues with his BB but he was also claiming he could feel some flex while climbing with his loaded bike. He is shopping for a new crank right now. Both my XT and his LX are touring cranks as far as chain ring sizes. They are NOT set up for MTB'ing. We carried comparable loads, obviously rode the same routes but I do weigh about 30 lbs more than he. I've never felt my XT crank flex or miss a beat.

I had an LX on another MTB and replaced it. I think my XT crank is heavier duty, I think it comes with a better BB but could be wrong and besides you can get BB's anywhere so thats easy to upgrade. I'm happy with my XT and would highly recommend it. It's by far one of my favorite cranksets no matter what type of bike touring or mountain. Not sure how helpful this is.

There are some very nice cranks for touring from Sugino, Velo Orange stocks their Cru models...all using square taper BB's which isn't a bad thing. You might want to check them out. Thats where my friend is headed I believe.

cyccommute 

There's a slight weight difference between XT and SLX but at $90, I suspect you are talking about Deore level or old LX. The weight difference between XT and Deore is much larger because the Deore (and old LX) use steel rings and solid crank arms. The finish on the Deore level is also not as nice nor are the bearing sets.

On the plus side, the Deore is going to work just as well and for as long as the XT, you just don't have the bragging rights.

For touring, I'd suggest finding a trekking crank (48/36/26) crank in either (you can find the XT version on-line from Europe). Swap out the 26 for a 22. I would also suggest the external bearing cranks because they are dead easy to install and work on.

GeoKrpan

You're heading to South America. It might be an advantage to go with a good old square taper bottom bracket.
It would be the easiest to find a replacement for should the need arise.

MichaelW

Shimano change their tech each year so XT of a few years ago is quite different to current XT.
The middle ring of 2010 XT is made of carbon fibre/steel mix. This may be OK for racing but I wouldnt trust it for a long tour.
Deore has an all steel mid and small ring. I'm not sure if the outer aluminium ring is as tough as the XT outer, usually Deore use a lower grade of alu.

Basically, Shimano have given up making simple, durable, tough components, they are light and snazzy or cheap and soft. The days when XT was the best, most cost-effective stuff for touring are long gone.

The advice to look at older style square taper systems is sound. High quality BB units last for much longer than other styles. You can get chainsets with tough Alu outer and mid rings and good steel inner ones.
I have never found stiffness to be a big deal with cranksets or BB units. Maybe it is for racers or really big, strong guys.

eofelis 

I went with XT because I wanted a 165mm crank arm length. Can't get that size in LX. I had to scour the net and ebay to find them! I got a used set (put it on my mtn bike), and a new set for the LHT.
My SO got a set of XT cranks in 172.5mm, very hard to find.

pacificcyclist

Most of the flexing usually don't occur with mountain cranksets, but rather with the quality of the frameset. The idea of buying a touring bike is to find a frame geometry and sizing that fits you really well while not compromising on frame stiffness and riding comfort loaded or unloaded. The flexing most riders will experience with touring bikes in general is with fish tailing, the rear oscillation that's generated either by pedaling or standing up while attacking a hill can be unnerving. For the most undiscerning rider, the LX or XT won't make a difference in terms of stiffness. XT gets you more bragging rights for say a few months before the scuff and scratch marks from leaning the crank against a high ledge or a parking meter sets in and makes it not so good looking!

If you are building a touring bike from scratch, you can look into the Sugino XD crankset. They come with good touring chainring setup starting with a 46T as a big chain ring. You can opt for a normal square taper; this you can splurge a bit with a Philwood or a Chris King, then you don't need to worry about overhauling the BB too often on a tour!

fietsbob

You really don't need a XC race bike crank on a touring bike , just need the ratios.

Low ones make the long climbs less fatiguing . 22t, but 24 is OK


I have kept using the M730 110/74 cranks for 20 years..

the chainrings, many would consider a down grade, are steel, all 3 ..

cyccommute 

Or you could buy an external bottom bracket crank and splurge on a Chris King external bottom bracket. Replaceable cartridge bearings that need no more service than a square taper bottom bracket and they are easier to work on.

ocho

I've had mountain bike cranks flex, swapped them out using the same frame and end of flex. My friend with the LX crank rides a Salsa Vaya, and I ride a Salsa Vaya so the frames are "pretty " similar.

pacificcyclist

Hi Ocho,

The reason why I said mountain cranks are supposed to be harder to flex is due to the needs of mountain bike riders who put their bikes through a lot more stress, abuse and torquing in 6 to 8 or even 10 foot drop offs that if the cranks constantly flexes, then eventually it will break. There will be continual liability issues with Shimano and that is not good. Mountain bikers are finnicky people you know. But that is not to say that you can not flex it. The most likely scenario and I had experienced it myself twice already and had almost forgotten cause I now have a Philwood is the short lifespan of the LX bottom bracket. It just died too quickly and developed a very slight noticeable play on the spindle. This will give you a flexing feeling when you pounce on the pedal. I went through 2 LX BB before I upgraded to XT. That went a bit longer before it too developed the same play.

Usually higher grade mountain components like XT and XTR are designed to be used and last only on race day or days only. They are designed to be light weight and not necessarily durable. Most tourers would suggest that you skip the mountain cranks and go with the Sugino XD 500T which is a commonly used crankset with the touring crowd and then customize the gear inches to your liking. I had used it and liked it on my previous road touring bike.
I use an old XT crankset square taper mated to a Philwood on a 26 inch touring bike now with custom chain rings and have never been happier with the setup.

geachyguy

Hi,
Thanks everyone for all the responses so quick. This is very helpful as I hope to make my decision within the next couple days.

About the square taper BB's, their advantage is that this is how most bottom brackets used to be? So replacing it would be easier, should the need arise?

Also, does anyone know of a good place to buy the Sugino crankset? I searched for "Sugino XD 500t" and got pretty meager results.

Thanks again, you guys are really priceless.

geachyguy

Also, cyccocommute (or anyone else) could you tell me more about "external bottom brackets" such as the Chris King? What are the advantages?

GeoKrpan

You will have a far easier time finding a square taper bottom bracket in South America than a bottom bracket for LX/XT cranks which are not square taper.
XT/LX cranks use an "external" bottom bracket and they would be rare in a third world country.

Here's a link to Jenson USA's square taper CRANKSET page.
https://www.jensonusa.com/store/sub/1...0&pricemax=900

The Shimano Alivio looks pretty good at $34.65, 22-32-42, as does the FSA Dynadrive for $49.99, 22-32-44.
They have Sugino XD600 cranksets for $135, 26-36-46.

Link to Jenson USA's square taper BOTTOM BRACKET page.
https://www.jensonusa.com/store/sub/1...0&pricemax=300

The Shimano UN54 bottom bracket is a sweet deal at $21.99.

fietsbob

External BBs are needed as the tube Spindles of the latest stuff are too big for 1/4" ball BBs ,
internally.
Chris King and Phil Wood make their own , the rest come across the Sea.

externals use smaller balls and are right out there.. but you will be up to date with Marketing's
latest 'must have'.

GeoKrpan

"External" means the bearings are outside of the bottom bracket shell. The crank spindle is hollow and lighter than the solid spindle of a square taper BB.

The bearings are spaced farther apart which supports the spindle better.

Theoretically there is an advantage but in the real world, I don't think so. I have every kind of bottom bracket.

Chris King makes high quality external BBs. They are expensive.

Many people say square taper BBs are more durable than external BBs.

I just replaced the BB on my fixie with a Interloc Racing square taper BB. It's as sweet as anything I've ever used.

cyccommute 

The larger diameter hollow spindle on external bottom bracket cranks is noticeably stiffer and lighter than square taper bottom brackets. However, the real advantage of external bottom bracket cranks is their ease of installation and maintenance. It takes only a couple of tools to install or remove a Shimano external BB crank. A 5 mm allen is all that is needed to tighten the arms onto the spindle or to remove it. If you have to replace the bearings...not something that happens any more often than replacing an internal BB...you could remove the BB with a pair of pliers.

To do the same operations with a internal BB requires 4 or 5 heavy tools. For touring, the external BB just makes sense.

ullearn

Go LX, it will work just fine and forget about weight; we are not pro's.

balindamood

I would not go on long tours on any XT stuff built in the last ten years (see comment above regarding XT moving towards racing). I would not go to a 2nd or 3rd world country with anything but a square taper BB (replacements will be impossible to find), which also pretty much nixes most of what Shimano has made in the last 10 years. Trying to save 200 grams of crank weight on a bike loaded to 70 lbs of touring gear makes no sense to me. Steel chain rings will last longer too, if you can find the appropriate size.

GeoKrpan

I understand how they work, I have them on a couple of my bikes.
If you need a new BB while on tour you will be visiting a bike shop, no need to carry BB tools.
They are lighter but not so much as to be a must have.
I would have liked it if they were a significant improvement over square taper or splined but it just doesn't seem that way to me.

GeoKrpan

Shimano still makes good old square taper stuff.
I second that on steel chainrings. They are usually riveted but the whole crankset usually cost less than an aluminum big ring.
Surly says that when their steel chainrings wear out, flip them and they'll go lots more.
People are willing to pay a premium for them.

hybridbkrdr

Is there any truth to the idea that Shimano Alivio and Sora chainrings last longer than Deore or higher because of the material used?

GeoKrpan

If Alivio and Sora chainrings are made of steel then they'll last longer.

cyccommute 

You aren't the only one who reads these posts. Geachguy is asking about options and the differences between cranks. If something happens to a crank in the middle of nowhere -not an event that's all that likely to begin with - an external BB crank requires less specialized tools to remedy the problem. It really is a simpler superior crank.

It's not just saving 200 grams of crank weight. How likely do you think it's going to be to find a tool to remove a square taper Shimano bottom bracket and a replacement for that bottom bracket in the Backofbeyond? Like I said above, you could remove and install an external BB with a pair of pliers. If you used a BB with removable cartridge bearings, you'd be likely to find those size bearings since they are a standard generally used bearing size.

The XT equipment...well maybe not this year's hubs...is highly durable. I have XT and XTR equipment that I expect will last for decades because it's not really all that delicate.

GeoKrpan

You're not going to find ANY BB in the middle of nowhere, you'll HAVE to find a bike shop. If you're in a third world country you probably won't find a external BB but you would be certain to find a square taper. It may be a loose bearing BB but it will work. Speaking of loose bearing BBs, they've got them all beat for reliablity. When a cartridge bearing BB goes out (square taper, splined, or external), it's toast, while a loose bearing BB can be fixed.