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I measured several combinations , but does anybody know if a 39/30 (without the 52 ring) shimano triple will clear the joke?
 

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I wouldn't so much worry about the rings clearing as the actual cranks not hitting the stays, as road cranks are generally designed around much closer Q-factors. As an example, I have attached a shot showing the Shimano LX M580 cranks and Shimano R700 compact road cranks. On my MTBs I only have about a fingers thickness between the cranks and stays using MTB cranks (or about the depth of the crank arms), so it'd didn't and won't work for me on any of my bikes. I bought the R700 compact crank hoping to use it on my KM frame, but didn't research it enough and only found out when I got it that road cranks only come in either 68mm or 70mm width, not 73mm which is what the KM is.
 

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mvi said:
I measured several combinations , but does anybody know if a 39/30 (without the 52 ring) shimano triple will clear the joke?
Im running a set of road triple Rotor cranks in my Jet9,30/39 & removed the large outer ring & they fit fine.

But as Lynx said you would need to check your Q factor
 

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muzzanic said:
Im running a set of road triple Rotor cranks in my Jet9,30/39 & removed the large outer ring & they fit fine.

But as Lynx said you would need to check your Q factor
And the crank setup recommendations on the Niner site
 

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road Triple cranks run a wider Q factor than there double counterparts. If you went with an older 3 piece crankset you could get a BB wide enough to make it work. With the current OBD style cranks it could be close, might be worth finding a LBS with one in stock and take your frame down to check fitment.
 

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mvi said:
I measured several combinations , but does anybody know if a 39/30 (without the 52 ring) shimano triple will clear the joke?
156mm Q-Factor will fit in terms of crank arms, but the chainstay/yoke clearance area for the granny ring and the middle ring will be the determining factor of how close you can get. Check this thread, and you'll see that even with the largest recommended 2 x 10 crank from SRAM (26/39) - some are having chainstuck issues. The same may or could occur with the cranks you are wanting to run. In any event, I wouldn't hesitate to install some zip ties around the yoke area to keep that chain at bay. Pictured in that thread.

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muzzanic said:
Im running a set of road triple Rotor cranks in my Jet9,30/39 & removed the large outer ring & they fit fine.

But as Lynx said you would need to check your Q factor
The Rotor crank has a fully adjustable chainline and a unique bottom bracket solution. Whether it works says nothing about conventional road triples.

I second what customfab said.
 
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