crank and 130mm disc hubs for nashbar cyclcross frame



bigringer

New Member
Mar 4, 2010
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i have a nashbar cyclocross frame that i have built into a commuter and enjoy riding very much. i am currently using a xtr m950 crank with 46-34-24 gearing. i am thinking about switching to a compact double crank and 48-34 gearing. i tried mounting my dura ace fc-7701 crank and the crank arm doesn't clear the chain stays. i tried it on my xtr bottom bracket that is a 112.5 and it still doesn't clear. any ideas?
my other issue the bike comes with disc brake tabs and 130mm spacing. haven't been able to track down a 130mm disc hub.
 

alfeng

Well-Known Member
Jul 23, 2005
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bigringer said:
i have a nashbar cyclocross frame that i have built into a commuter and enjoy riding very much. i am currently using a xtr m950 crank with 46-34-24 gearing. i am thinking about switching to a compact double crank and 48-34 gearing. i tried mounting my dura ace fc-7701 crank and the crank arm doesn't clear the chain stays. i tried it on my xtr bottom bracket that is a 112.5 and it still doesn't clear. any ideas?
my other issue the bike comes with disc brake tabs and 130mm spacing. haven't been able to track down a 130mm disc hub.
You have multiple option ...

The easiest is to buy a 118mm (e.g., 6503) Octalink BB ... this was the solution I used when I mounted a Road crank on an alloy Hardtail frame whose stays ALSO conflicted with the chainring on a Road crank ...

Alternatively, you can find/buy the 5-arm spider for your 950 crankarms OR install a 48t chainring (either a Shimano DH chainring OR a now-hard-to-find AVATAR chainring made for the XTR BCD).

As far as the 130mm disc hub ... I'm not sure there is such an animal (re-measure your rear stays) ...

If you could live with fewer gears, you could convert a Shimano rear hub by transplanting a 7-speed Freehub from an Shimano ACERA rear hub, shorten the axle, etc.

If you are really clever, you can machine down the disc mount so that it is ~5mm closer to the flange ... remove the spacer, and shorten the axle.
 

alfeng

Well-Known Member
Jul 23, 2005
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BTW. Here's a picture of a frame that needed a longer BB spindle to use a Road crank -- in this case, an ISIS Road crank & 118mm BB ...

I subsequently installed a 118mm 6503/Octalink BB & Road crank because I wasn't happy with the ISIS BB.