# Mountain bike crankset on my road bike



## tkpmep (Jul 21, 2013)

I have a 2012 Giant Defy Advanced 1 which is an exceptionally comfortable ride, so comfortable in fact that I'm thinking of doing some light touring on it using a Freeload rack at the back. The componentry are SRAM Force, with a compact (50/34) crank in front and a 11-32 cassette at the back. I'd like to get a 42/28 mountain bike crankset in front to make hills easier when loaded, and thought that a PF30 X9 or X0 crankset would do the trick and would make for a much more useful range of gearing. My LBS looked into it and came back to me saying that this would not work as the mountain bike cranks were too wide to fit into the existing bottom bracket - he said he had talked to SRAM and they confirmed this. This somehow seems wrong - has anyone succeeded in fitting a SRAM mountain bike crankset onto a road bike such as my Giant while keeping the road derailleur and shifters?

Thanks in advance

Thomas Philips


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## SoFlaNut (Sep 19, 2011)

Go with Crank Brother Egg Beaters


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## tihsepa (Nov 27, 2008)

SoFlaNut said:


> Go with Crank Brother Egg Beaters


What? He is asking about a crankset.


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## redondoaveb (Jan 16, 2011)

Here are some Sram frame fit technical docs that might help you out a little bit. Best I can do for you.
http://cdn.sram.com/cdn/farfuture/d..._frame_fit_specs_gen_000000002876_-_rev_b.pdf


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## Nubster (Jul 8, 2009)

Why not a road triple?


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## Slow Eddie (Jun 28, 2004)

Or a WiFli RD and cassette. EDIT: just noticed the cassette range.


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## bluesky6 (Jul 23, 2013)

If you can figure out how to use a square taper BB, the Sugino Alpina 2 is an option.


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## tednugent (Apr 26, 2010)

tkpmep said:


> I have a 2012 Giant Defy Advanced 1 which is an exceptionally comfortable ride, so comfortable in fact that I'm thinking of doing some light touring on it using a Freeload rack at the back. The componentry are SRAM Force, with a compact (50/34) crank in front and a 11-32 cassette at the back. I'd like to get a 42/28 mountain bike crankset in front to make hills easier when loaded, and thought that a PF30 X9 or X0 crankset would do the trick and would make for a much more useful range of gearing. My LBS looked into it and came back to me saying that this would not work as the mountain bike cranks were too wide to fit into the existing bottom bracket - he said he had talked to SRAM and they confirmed this. This somehow seems wrong - has anyone succeeded in fitting a SRAM mountain bike crankset onto a road bike such as my Giant while keeping the road derailleur and shifters?
> 
> Thanks in advance
> 
> Thomas Philips


looks like you have a SRAM GXP BB. 

According to SRAM's website, the Truvativ X9 & X0 10-Speed Crankset are available with a GXP BB

Maybe you should call up SRAM tech support yourself.

Another alternative... ditch the WiFLi RD and fit a MTB one that would be good for 34T or even 36T cassette.


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## ziscwg (Apr 19, 2010)

SoFlaNut said:


> Go with Crank Brother Egg Beaters


I prefer the General Mills Egg Beaters. The consistancy of the Crank Bros Egg Beaters is too firm when you pour them into the pan. The Crank Bros go "clunk" into the pan, while the General Mills goes "woosh", then sizzle.


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## ziscwg (Apr 19, 2010)

tednugent said:


> looks like you have a SRAM GXP BB.
> 
> According to SRAM's website, the Truvativ X9 & X0 10-Speed Crankset are available with a GXP BB
> 
> ...


I use an X.9 mid cage for my 11-32 climbing set up. If you go this route, make sure you put an inline adj in. The mtb setups don't have an a cable adjuster like road RD.


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## ziscwg (Apr 19, 2010)

tkpmep said:


> I have a 2012 Giant Defy Advanced 1 which is an exceptionally comfortable ride, so comfortable in fact that I'm thinking of doing some light touring on it using a Freeload rack at the back. The componentry are SRAM Force, with a compact (50/34) crank in front and a 11-32 cassette at the back. I'd like to get a 42/28 mountain bike crankset in front to make hills easier when loaded, and thought that a PF30 X9 or X0 crankset would do the trick and would make for a much more useful range of gearing. My LBS looked into it and came back to me saying that this would not work as the mountain bike cranks were too wide to fit into the existing bottom bracket - he said he had talked to SRAM and they confirmed this. This somehow seems wrong - has anyone succeeded in fitting a SRAM mountain bike crankset onto a road bike such as my Giant while keeping the road derailleur and shifters?
> 
> Thanks in advance
> 
> Thomas Philips


With an 11-34 cassette and 50/34 crankset, you get fairly low gears. 

If you go mountain, you may have a top end problem. I will assume you are climbing. You usually get to go down after the climb. Spinning out on a descent at 30 mph would kind of suck IMHO.


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## Nubster (Jul 8, 2009)

ziscwg said:


> I use an X.9 mid cage for my 11-32 climbing set up. If you go this route, make sure you put an inline adj in. The mtb setups don't have an a cable adjuster like road RD.


A long cage SRAM Apex RD will work with a 32T cassette. I'm running a 12-32 on my Allez because I suck at climbing.


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## tkpmep (Jul 21, 2013)

The BB is PF30. Unfortunately SRAM road bike cranks are 68 mm wide, while the MTB cranks are 73 mm wide. Apparently Shimano makes MTB cranks that are 68 mm wide, and I'm looking for an adapter that will allow a Shimano crankset to work in a SRAM PF30 BB. Question: Will an SRAM chain work on a Shimano MTB front crank / chain set? Will a SRAM Force derailleur shift over Shimano chainrings?


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## RaptorTC (Jul 20, 2012)

You should be able to find a 46 tooth big ring for your compact. Shouldn't be too hard to find since they're used in cross. Not quite the 42 that a mtb crankset would provide, but would make climbing easier than a 50.

And also, I'm currently rocking Sram Apex shifters/both derailleurs with a Shimano Tiagra crankset/rings with no problems at all. So as long as the Shimano crankset fits it shouldn't pose problems.


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## masont (Feb 6, 2010)

With a braze on you're going to have a real problem getting the front derailleur low enough to functionally shift with a 42 tooth chainring on a bike designed for a 50 tooth chainring.


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## Camilo (Jun 23, 2007)

> Another alternative... ditch the WiFLi RD and fit a MTB one that would be good for 34T or even 36T cassette.


This sounds like a good idea, especially if he can modify the crank to get a decent low front chainring like a 30 or 28.



masont said:


> With a braze on you're going to have a real problem getting the front derailleur low enough to functionally shift with a 42 tooth chainring on a bike designed for a 50 tooth chainring.


Just an FWIW - I can get my braze on FD to work with a 44 large ring. I'm not using Sram, but it is a conventional Shimano road triple braze on FD which I'm using with a 44-34-28 MTB crankset. The only point I'm making is that this FD can be lowered enough to work well with that crank, which gives me hope that a Sram FD can be adjusted down far enough for a 44, maybe even a 42 chain ring.

I'm not really hep to the varieties of low-geared double cranks available. I know that the FD/compact crank combo is limited by a 16t difference. Does this mean that it would work with a 44-28, if that crankset exists? I think a 28 front X 36 rear would be a nice low gear for loaded touring.

I'm also assuming that the Sram double front shifter can work well with any double crankset, regardless of if it's "MTB" or "road" assuming it can be adjusted downward for the smaller rings. (like my experience above - it's a non-Shimano crank)



ziscwg said:


> With an 11-34 cassette and 50/34 crankset, you get fairly low gears.


We'll just have to assume he knows how low that gearing is and wants lower, since he asked the question. 



> If you go mountain, you may have a top end problem. I will assume you are climbing. You usually get to go down after the climb. Spinning out on a descent at 30 mph would kind of suck IMHO.


Again, we'll have to assume that he knows what high gearing he actually wants and that he doesn't care if he spins out at 30 mph loaded touring. I really can't imagine wanting to go really fast while touring. Most recreational road riders don't care all that much either - very few road bike "duffers" actually like to go much faster than 30 mph (I do - I'm like you, and I like to pedal downhill as fast as I can up to about 110 rpm)


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