Author Topic: Cranks for Rohloff  (Read 4046 times)

edwin

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Cranks for Rohloff
« on: November 06, 2010, 06:54:13 PM »
Hi

My bottom bracket has started to have quite alot of play in it and so i fear failiure may be around the corner. I would like to replace my crankset with external bearing type. i am thinking of truvativ stylo http://www.chainreactioncycles.com/Models.aspx?ModelID=23243. the spec sheet states a chain line of 51mm (assuming thats centre ring) does any body know what the chain line you get on the outer ring is. suggestions of other similar cranksets that work with rohloff would be welcome

Andre Jute

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Re: Cranks for Rohloff
« Reply #1 on: November 07, 2010, 01:32:03 AM »
5mm further out, making 56mm. You want 54mm centre line for the Rohloff. Maybe someone with the Stylo can tell you how much side to side adjustment it has. The Shimano external bottom bracket types I looked at come with adjustment shims, one of which is 2mm. Two mil will bring you to 53mm on the middle fitment and by shifting the other way 54mm on the outer fitment.

Andre Jute 
 http://www.audio-talk.co.uk/fiultra/BICYCLE%20%26%20CYCLING.html

edwin

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Re: Cranks for Rohloff
« Reply #2 on: November 07, 2010, 02:13:03 PM »
as i have a 68mm bottom bracket shell i will need to use the 2x 2.5mm (assuming they are this size) spacers to make up to 73mm, does any body know if i can put both on one side to change the chainline. both on right hand side should bring middle ring to 53.5mm or both on left should bring outer ring back to 53.5. will 5mm of spacer on one side mean that there isnt enough of the cup thread in the bottom bracked shell on that side.

PH

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Re: Cranks for Rohloff
« Reply #3 on: November 07, 2010, 03:34:57 PM »
You could probably pinch a couple of mm by offsetting the EBB shell. 
Out of interest, what are you hoping to gain?  Do Thorn offer any external BBs on any model?  I'm just wondering if the EBB insert is ready to take the cups or if it needs facing the way most new frames do.
I've stuck with square taper, from road bike to touring, I'm not adverse to change, they've always served me well and I can't see any advantage.

edwin

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Re: Cranks for Rohloff
« Reply #4 on: November 07, 2010, 04:54:17 PM »
Hi

I don’t have an ebb (or a thorn build) I have adjustable dropouts with standard 68mm bottom bracket shell. As my bb is dying I would like to use this opertunitity to try the external bb style crankset, I don’t really want to turn this thread into discussion about advantages/disadvantages of internal/external bearings, but am under the impression larger hollow axle with 2 piece crankset may be stiffer/stronger also larger size of bearings may be more durable, may also be some weight advantages.

im really looking to find out if any one has made the same or similar crankset work with rohloff chainline

i am also open to suggestions of other suitable cranksets, but was under the impression that road cranks chainlines were far of that of rohloff (designed to work with outer mtb chainring)