Touring - Any Rocky Mountain Sherpa 30 owners upgrade the gearing?

I need to get rid of the road gearing my Sherpa came with.
I have been looking for a Shimano Deore 48-36-26.
I want the hardened rings so which model do I choose. The XT?

On the Shimano website they don't seem to use the term "hardened" with respect to the rings.

The XT comes with all aluminum rings.

The LX comes with aluminum rings on the outer and middle, and a steel inner ring.

Something else to think about before you go down that path. The chainline for those cranksets, LX and XT is 50 mm. It's meant to go with a 135 mm spaced hub. If you go with those cranksets you may be inviting more surgery than you intended.

Any reason why you don't just swap chainrings for the ones you want?

Speedo

Because the FSA stuff is junk. It sounds like the Titanic sinking whenever I need to stand on the pedals. And I need to swap all three rings.
I noticed the 09' XT is now "composite". Since Rocky faces all their BB's and the new 9spd cranks are external bearings I am thinking it should line up pretty close.

You're on the right path with a stock Shimano touring style crank. Because you have STI brifters, don't fool with the chainrings, just swap cranksets.

If it was my bike, I'd stick with the older MTB Octalink units. Shimano seems to think that these are here to stay, (unlike the road Octalink) so BBs are going to be around when you need them. It will be easier to add spacers if you have chainline issues with the Octalink BB. Plus the drag on the lower end external bering BBs is unbelieviable, unless upgrade.

The cheaper steel chainrings work really well. They are stiff, shift great, and wear slowly. Your Sherpa is a touring bike, afterall. Weight isn't that importaint.

Because the FSA stuff is junk. It sounds like the Titanic sinking whenever I need to stand on the pedals.


Good to know. Too bad.



I noticed the 09' XT is now "composite". Since Rocky faces all their BB's and the new 9spd cranks are external bearings I am thinking it should line up pretty close.

The one with the composite ring is the FC-M770. It's the more mountain bikey of the cranksets. It comes with 44-32-22 rings. The FC-M771-K has all aluminum rings. It's the more tourey of the two. It comes with 48-36-26 rings.

I think you'd still end up with a 50mm chain line. I'm not saying that you couldn't get something to work, but it wasn't built to go together with your Tiagra FD and STI shifters. It might take some playing with.

Another alternative, the Sugino triple crank. You can get the square taper BB to match your current chain line. I've been riding one Sugino for years, and just bought another. I think they are pretty nice. The standard rings have pins and ramps. and should work with your STI.

Speedo

I was thinking of this one.
http://bike.shimano.com/publish/content/global_cycle/en/us/index/products/mountain/deore_xt/product.-code-FC-M771-K.-type-fc_mountain.html

I was thinking of this one.
http://bike.shimano.com/publish/content/global_cycle/en/us/index/products/mountain/deore_xt/product.-code-FC-M771-K.-type-fc_mountain.html

Yeah, that's the FC-M771-K. It shows all the chainrings as aluminum.

Speedo

Another alternative, the Sugino triple crank. You can get the square taper BB to match your current chain line. I've been riding one Sugino for years, and just bought another. I think they are pretty nice. The standard rings have pins and ramps. and should work with your STI.
What about this one?
http://www.velo-orange.com/suoldlotr.html


I need to get rid of the road gearing my Sherpa came with.
Still recommend the Sherpa otherwise? (I'm looking to replace a bent bicycle.)

I would still recommend a Sherpa. Road gearing is pretty much standard on most factory bikes.

Yeah, that's the FC-M771-K. It shows all the chainrings as aluminum.

Speedo

Not available in North America?
Unless anyone has any leads??

Not available in North America?
Unless anyone has any leads??

Looks like the 2008 model (essentially the same) is available at Jenson (http://www.jensonusa.com/store/product/CG306A03-Shimano+Deore+M771k+Front+Chainwheel+08.aspx). Oh, maybe not, they're out of stock.

Man, I'm shocked, but this does seem to be hard to find in the US. I'd call Jenson, at least they are carrying it on their web site. It is also on a couple of European sites. Maybe they'll ship.

I also found an E-Bay (http://cgi.ebay.com/Deore-XT-2008-HOLLOWTECH-II-Crankset-FC-M771-K-wz-BB_W0QQitemZ310095116631QQcmdZViewItemQQptZLH_DefaultDomain_15?_trksid=p3286.m20.l1116) store that is shipping them from Japan.

Good luck!

Speedo

My LBS is going to order me the LX as the XT is unavailable in NA.
The 48/38/26 gearing should be good for my prairie riding. To bad about the XT though.
http://bike.shimano.com/publish/content/global_cycle/en/us/index/products/mountain/deore_lx/product.-code-FC-M583-K.-type-fc_mountain.html

I think you'd still end up with a 50mm chain line. I'm not saying that you couldn't get something to work, but it wasn't built to go together with your Tiagra FD and STI shifters. It might take some playing with.



I've been running mountain bike cranks with STI and Tiagra for a long time. No shifting issues at all. Both bike do have 135mm hubs but those hubs make sense for touring bikes anyway;)

I've been running mountain bike cranks with STI and Tiagra for a long time. No shifting issues at all. Both bike do have 135mm hubs but those hubs make sense for touring bikes anyway;)

Thats good to hear.
I am going to bring the bike to the shop when he swaps out my old crankset. He doesn't anticipate any trouble with the chainline or the FD. He has also agreed to upgrade the BB to XT.

Whaaaat? Not just the chainrings? A new crank?

This is my winter project. Was my winter project. Now it's my LBS's project.

:cry:

Whaaaat? Not just the chainrings? A new crank?

This is my winter project. Was my winter project. Now it's my LBS's project.

:cry:

I don't follow you.
I don't consider this a project. I'm just swapping cranks. I know the owners, I've bought bikes there since 1983. And he invited me to bring the bike in. But why spend money on labour when I can do it myself? I would have to buy a tool for the FSA, and thats going anyways. I've got 2K into it, so another few bucks is no big deal to me. Besides, I'm allowed one free tune and now that the bike has 3000 km or so its time to let him have a look at it before my warranty is done.
Now, when I built my Nishiki Continental (including the wheels) that was one of my winter projects.
The FSA stuff does not belong on this bike. Wrong gearing, noisy and flexy.

What's a piece of cake for some isn't at all natural for others, like me, that's all.

For me it's a project, I have never done such work on my bikes. I don't mind studying up on it and am quite capable of figuring things like this out and asking questions when I get stuck, but, it's a lot different for me now than switching out chainrings.