Crankarm / chainstay clearance?

[cid499]

Picked up a Rotor Agilis crank awhile back from the classifieds here. I ran it for awhile successfully on my Ridley Compact road bike with a Dura Ace 7800 BB.

I then tried to move it over to my Bianchi Roger (single speed CX bike). This bike also has a 68mm BB shell width. When I went to tighten the crankarm onto the spindle, I noticed the crankarm was hitting the chainstay.

Is this just an incompatible combination due to the low Q-factor of the Rotor cranks and the beefy chainstays of my frame? Or am I missing something here...

[lonoeightysix]

Which crankarm is rubbing (driveside/non-driveside)? How much room is available on the side that isn't hitting?

[oldpotatoe]

Picked up a Rotor Agilis crank awhile back from the classifieds here. I ran it for awhile successfully on my Ridley Compact road bike with a Dura Ace 7800 BB.

I then tried to move it over to my Bianchi Roger (single speed CX bike). This bike also has a 68mm BB shell width. When I went to tighten the crankarm onto the spindle, I noticed the crankarm was hitting the chainstay.

Is this just an incompatible combination due to the low Q-factor of the Rotor cranks and the beefy chainstays of my frame? Or am I missing something here...

Not uncommon on cross bikes with splayed/fat stays for fatter tires. Need a more 'cross' type crank that has more clearance.

[konstantkarma]

I noticed a similar issue when I put a Veloce compact crank on my cross bike (Gunnar Crosshairs). I ended up having just enough clearance for the inner chainring and chain to clear the chainstay. However, the cross crank that was on it previously had plenty of room. I attributed it to the geometry of the chainstays on the Gunnar.

[cid499]

It is the drive-side that is rubbing. (For the cranks I am using, the spindle is permanently attached to the non-drive side and the drive-side presses on).

Luckily Rotor designed quite a bit of adjustment in the spindle length and I was able to get it to clear, although only with about 1.5 mm of clearance on each side. Hopefully the frame and cranks are stiff enough that it won't be an issue.

[merlinmurph]

I just got a used 'cross bike (IF Planet-X) and am considering putting a triple on it. I'll keep chainstay clearance in mind.....
Murph

[AngryScientist]

i've got a GXP Force crankset on my cross bike, chainstay/crankarm clearance is super close, just barely clears, makes me a bit uneasy actually.