# Anyone here run Mt. double cranksets on their cx rigs?



## OldEndicottHiway (Jul 16, 2007)

Still looking for a lower gear for the off road...(steep, muddy, loose, sandy, rocky dirty-long climbs around here)

My cx rig is designed to take triples if need be...don't want. The Campy PT 36/50 road compact I'd originally wanted, won't work. 

At this point, I'm opting for sram x9 28/42.

Anyone have experience with it?

(P.S. did a quick search..came up with little. Sorry if this is an old subject).

P.P.S, would be matched to a 12-25 cassette, 10sp chain, and x9 FD).


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## 196nautique (Sep 23, 2005)

Kind of funny, here is a post I made when you were building your bike-

I ride my CX bike all over the fire roads in NCW also. Most important thing is gearing. Make sure to either get a triple crank, or at very minimum a compact double and use a MTB rear derailleur and a MTB cassette. I see others have recommended a compact and a 11-28 cassette, but the Cascade foothills can be steep as I am sure you already know.

I have a 50-34 crank, and an 11-34 cassette. Sometimes I wish I had more gears. I have never wished I had fewer.

Also, get the fatest tires possible. The gravel roads can be a bit harsh on narrower tires.​
Anyway, If you have a triple crank, just put a bash guard on the outer ring, then it is a double. I have that same crank (x9 42-28 & x9 FD) but haven't spent enough time messing around with setting it up. I briefly put it on, but was having trouble with BB spacing, and a road FD moving out far enough to get into the big ring. I bought the x9 FD and plan to give it another try, but haven't gotten around to it. With Sage Hills opening in 10 days, I am sure I will be trying again soon. Sage on a cross bike is loads of fun.


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## OldEndicottHiway (Jul 16, 2007)

196nautique said:


> Kind of funny, here is a post I made when you were building your bike-
> 
> I ride my CX bike all over the fire roads in NCW also. Most important thing is gearing. Make sure to either get a triple crank, or at very minimum a compact double and use a MTB rear derailleur and a MTB cassette. I see others have recommended a compact and a 11-28 cassette, but the Cascade foothills can be steep as I am sure you already know.
> 
> ...



Thanks. I think I do remember your post. 

I thought bash gaurds were for teeny weeny cranksets...? But what do I know.

A 34 (low as a compact road will go as I understand) won't suffice, and neither will it _work on this frame_....no worries, I wanted smaller gears anyway for what we encounter off road around here. 

P.S. was it a road FD that wouldn't shift into your big ring, or the x9? I understand why a road FD wouldn't work, but an x9 FD with a x9 crankset...I can't imagine why it wouldn't work?

My original goal with this bike since I can't afford to buy a bike for every need/whim...was to make it a road/mt/cx "hybrid." Too much to ask? Maybe...

P.P.S. If I stick a triple on this bike (not to mention that they're fugly on "road" frames and I really don't want) I'd have to change out the RD to at least a medium cage I would think. Have a short cage on it now.


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## 196nautique (Sep 23, 2005)

OldEndicottHiway said:


> Thanks. I think I do remember your post.
> 
> I thought bash gaurds were for teeny weeny cranksets...? But what do I know.
> 
> ...


I hate triples as well, but a triple with a bash guard would be your cheapest, and easiest bet. You will not have to change your RD, just shorten your chain.


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## OldEndicottHiway (Jul 16, 2007)

196nautique said:



> I hate triples as well, but a triple with a bash guard would be your cheapest, and easiest bet. You will not have to change your RD, just shorten your chain.



Thanks so much for your input. Will double check the BB specs against the x9 FD. From what I understand, the x9 FD has more throw, and the x9 BB will work with 68 and 73 mm BB's. May need to check this out more.

The 34 or 36/50 compact road crank won't work because... the guy originally having the frame built up wanted a cx bike with the _option_ to stick mtb tires on it as well as a triple if he so chose to....hence, the chainstay is configured as such that even a small (34 compact) runs tooooo close to the frame for comfort. 

Again, no worries, I wanted smaller than a 34 anyway. 

Just hoping that the x9 is the wisest choice against other mt doubles on a cx frame, and wondering if folks here have eperience with it.


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## m_s (Nov 20, 2007)

Hypothetically it will work fine but there could be clearance issues. if your bike was designed around a triple with a 30t inner, I doubt something like an X9 28/42 double wouldn't work, but I couldn't say for sure.


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## atpjunkie (Mar 23, 2002)

*yes*

mountain doubles, MTB derailleurs and road shifters

shhhhhhh people say it doesn't work
one bike 48/36 one bike 46/34 11-28 and 11-30 cassettes, 8 speed


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## thatdrewguy (Aug 7, 2009)

*almost about to do the same x9 double thing*

I was talking with the guy at the shop about changing out my crankset. I'm running a XT crankset using only the two outer rings 32/44. I've been wanting to reduce the Q factor and also reduce the chain line angle and we came up using the x9 28/42.

I think the Q factor for the x9 is 156mm, my XT is at 166mm and there is enough clearance at the stays for a narrower set of cranks.

Will the x9 work for me?


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## OldEndicottHiway (Jul 16, 2007)

m_s and atp, thanks for the input.

Feel a bit better about trying this route.

atp, I saw somewhere back you had busted up your hip pretty well. Sorry about that and hope you're on the mend.


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## LC (Jan 28, 2004)

I'm starting my own trend, the Sub-Compact double crankset. If you live in the mountains 29/44T is basically a must have along with at least a 11-32T cassette.
5 Arm spider 94BCD is nice and stiff
http://www.amazon.com/Cannondale-CODA-Tarantula-Crankset-170mm/dp/B003HI6MJU

heard these exist in a double instead of a triple but I have never seen one.
http://www.origin-8.com/?page_id=91&short_code=Origin8+Sub+Compact&cl1=CRANK+ARMS+&+SETS


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## AndrwSwitch (May 28, 2009)

atpjunkie said:


> mountain doubles, MTB derailleurs and road shifters
> 
> shhhhhhh people say it doesn't work
> one bike 48/36 one bike 46/34 11-28 and 11-30 cassettes, 8 speed


Glad to hear it works.

When I can afford to bolt more money to a 'cross bike, I may do something similar. I'm a spinner, not a masher, especially in sand and mud, and I want my competition bike to be the best bike for the me that goes to a race, not the fantasy me that doesn't need those extra low gears.

Any trouble tuning the MTB derailleur and road shifter? I'd heard that the pull ratios are different.


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## m_s (Nov 20, 2007)

LC said:


> heard these exist in a double instead of a triple but I have never seen one.
> http://www.origin-8.com/?page_id=91&short_code=Origin8+Sub+Compact&cl1=CRANK+ARMS+&+SETS


It exists:

Origin 8 subs

I'm thinking of getting one of the 40-28s for my mountain bike to try out a double. They are cheap and not too heavy. I'm not sure what "INT OR8" is for a spindle type, but some are JIS and ISIS, so that would let you work around any chainstay clearance issues.

Really these are just normal mountain triple cranks with two chainrings, but it's a lot cheaper than doing any mods. I don't have my J and B login information with me, but these cranks are not expensive at all.

EDIT: Noticed these Kores just showed up too. 

http://www.jbimporters.com/web/Adva...tTwoId=MTB&CatThreeId=KORE&dfadfkawe45d9drh=3


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## ridenfish39 (Jun 20, 2008)

atpjunkie said:


> mountain doubles, MTB derailleurs and road shifters
> 
> shhhhhhh people say it doesn't work
> one bike 48/36 one bike 46/34 11-28 and 11-30 cassettes, 8 speed


They are some damn sweet bikes! My friend has an Ibis cx bike and I have always coveted it. 
As for gearing I use the 46/34 with an 11-28 also (10 speed), I think it's the perfect range.


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## atpjunkie (Mar 23, 2002)

*I'm a clydesdale*



ridenfish39 said:


> They are some damn sweet bikes! My friend has an Ibis cx bike and I have always coveted it.
> As for gearing I use the 46/34 with an 11-28 also (10 speed), I think it's the perfect range.


and I ride them on a lot of mtb style trails so the lower gearing helps me. I wind up running out of gears with a 38/27 traditional set up and push myself too deep into anaerobic debt when running classic gearing

thx, Ibis was the bike of my young man's dreams (early 80s MTBs) and when I got back into riding (mid 90s) they again took that place. I finally have my birds and am pretty pleased


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## BearSquirrel (Mar 30, 2011)

196nautique said:


> Anyway, If you have a triple crank, just put a bash guard on the outer ring, then it is a double.


No, it's a hobbled triple. My Cross Check shipped with a triple crank with the granny removed and they called that a double. It wasn't, it was a hobbled triple.

Real doubles have their lateral spacing adjusted to optimize chainline for both rings. In this configuration, you have good chainline to almost all the gears in either ring.

This is something that is not practical on a triple crank. Removing the big ring will give you a granny with lousy chainlines in the bottom of the cassette. However, since the middle ring on a triple IS centered you can remove the big and granny ring and call THAT a single.

Finally bashrings are practical on MTB triples because on many MTB courses the big ring is rarely used. Single cranks are very popular in MTB. I personally have to admit that I rarely leave my middle chainring on my local course midwest MTB course (it's a 29er, and inherently has higher gearing than a 26"). But on long sustained climbs on some road trips, I'm down in the granny. I only use the big ring in "cruiser mode" (when I use the MTB on the road).


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## misterdangerpants (Oct 23, 2008)

I'm going to run a similar setup on my CX rig and am using an MTB crankset (Cook Bros. Racing RSR) with only the outer chainrings. Planning on using a 40/29 or so, depending on what I can find.


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## atpjunkie (Mar 23, 2002)

*thanx OEH*



OldEndicottHiway said:


> m_s and atp, thanks for the input.
> 
> Feel a bit better about trying this route.
> 
> atp, I saw somewhere back you had busted up your hip pretty well. Sorry about that and hope you're on the mend.


first week back on the bike. did a semi-mellow cx ride on Sunday (made me very happy)
and have commuted (22 miles RT) T,W and tomorrow. 3 mos off the bike, my form has gone to sh!t. Back to work. Seems every time I get somewhere something knocks me back.
Just find a MTN Double that you can easily pitch the Granny (XTRs work too!)


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## 196nautique (Sep 23, 2005)

Finally got my setup working. And it works great!
A real mishmash of parts.
Force shifters
XX RD, and 11-36 cassette
x9 42-28 crank

And the final piece was......
Shimano 105 triple FD.

Biggest problem was the FD.
SRAM force would not travel far enough out.
SRAM x9 did not have enough clearance between the rear tire and the seat tube.

Glad I have friends that have lots of parts in their garage.

So I have a La Cruz with disc brakes and 29er gearing, that is loads of fun.
But when I plan to ride anything bumpy, I will take the real mountain bike.


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## macming (Dec 2, 2004)

Are there any other 2 x 9 mtb cranks besides the SRAM offerings? I don't think you can take a regular 3 x 9 and still keep a good chain line?

If you run a MTB crankset, do you have to put the bottom bracket spacers in to make the BB size 73mm equivalent? wouldn't that screw up the chain line?

Thanks!

Ming


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## misterdangerpants (Oct 23, 2008)

macming said:


> Are there any other 2 x 9 mtb cranks besides the SRAM offerings?


I have a lovely Rotor 2x9 crankset. Shimano XTR also comes in a double.


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## OldEndicottHiway (Jul 16, 2007)

macming said:


> *Are there any other 2 x 9 mtb cranks besides the SRAM offerings?* I don't think you can take a regular 3 x 9 and still keep a good chain line?
> 
> If you run a MTB crankset, do you have to put the bottom bracket spacers in to make the BB size 73mm equivalent? wouldn't that screw up the chain line?
> 
> ...



I found lots just by googling "2 x 10" and "2 x 9" as well as doing a search on eBay. Problem is, they're all ugly. At least to me. I wanted silver and I could not find one mtb 2 x 10 in silver. Not one. 

Shimano XTR and SRAM XO's...seen the price on those? It's like running Super Record on a dirty ol' cross bike. Why? What for?

As to your techie questions...I can't help really, not with any definitive answers. Throughout this process I've found I'm perhaps more befuddled by all the different BB, crank and derailleur configurations than before I started. 

Pictured below I'm running X9 FD and X9 2x10 crankset paired to 11-25 cassette, Campagnolo Chorus road shifters and RD... on a steel cx frame. Is that not funny or what? Chainlines pretty good so far that I can see. Runs like butter, and I have a _very_ versatile bike now. 

Best wishes to all on your rides this year.


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## turbogrover (Jan 1, 2006)

I run a Campy road triple on my MTB. I switch between 40/28 and 42/28 front rings depending on the course. You can run anywhere between a 30 and 27T granny on it. You can also usually get good deals on road triples.


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## macming (Dec 2, 2004)

OldEndicottHiway said:


> I found lots just by googling "2 x 10" and "2 x 9" as well as doing a search on eBay. Problem is, they're all ugly. At least to me. I wanted silver and I could not find one mtb 2 x 10 in silver. Not one.
> 
> Shimano XTR and SRAM XO's...seen the price on those? It's like running Super Record on a dirty ol' cross bike. Why? What for?
> 
> ...



I thought about this for a while, and picked up a Dura Ace 7800 triple. I have XTR cranks on my mountain bikes, and truth is, they are not any cheaper, in fact are MORE expensive than DA triples 

With a road crank, I know the chainline will be somewhat OK. Problem is that now I may need to look into a long cage derailleur. If I swap my DA short cage out, I'm thinking if using a XTR long cage in place. 

I'm going to try the triple out for a while and see how it feels. I was making up most of the hills OK with a 39/25 combination, so maybe a 30/25 combination will be good enough to hold me over.


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## macming (Dec 2, 2004)

turbogrover said:


> I run a Campy road triple on my MTB. I switch between 40/28 and 42/28 front rings depending on the course. You can run anywhere between a 30 and 27T granny on it. You can also usually get good deals on road triples.


Nice ride!  I'm way to big of a wuss to run full rigid now days


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## Kram (Jan 28, 2004)

So you're saying I can slap my MTB front derailler (top pull) on my cross rig and use my Sram brifters? This would make me happy if it worked (no need for a new front der or little roller thingie....)


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## m_s (Nov 20, 2007)

OldEndicottHiway said:


> I found lots just by googling "2 x 10" and "2 x 9" as well as doing a search on eBay. Problem is, they're all ugly. At least to me. I wanted silver and I could not find one mtb 2 x 10 in silver. Not one.


There's these but they still aren't cheap, and the BCD is pretty stupid IMO.


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## vaultbrad (Oct 21, 2007)

m_s said:


> There's these but they still aren't cheap, and the BCD is pretty stupid IMO.


Yup, stupid. 

I like the campagnolo triple turned double. I've thought of doing this with other cranks, but that campagnolo looks so good.


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