What current carbon bike has the stiffest BB?

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andy2
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by andy2

Sorry to rain on your parade but the Cannondale Evo has a bottom bracket stiffness of 55N/mm, so that would be about the 130th stiffest bb.
They have a high stw ratio but that is a function of head tube stiffness and weight. The actual figure for the Cannondale Evo is 139Nm/deg/kg with the Cervelo coming in at 137 Nm/deg/kg.
So they are leaders in stw, but not by much.
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Estelja
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by Estelja

I doubt it is an identical protocol test but Velocite claims 150Nm BB stiffness for their Magnus frame using an "EFBe analogous test apparatus":

http://www.velocite-bikes.com/magnus-frameset.html

Maybe Victor can chime in here to give it some relevancy to the Zedler test.

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Ramjm_2000
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by Ramjm_2000

andy2 wrote:Sorry to rain on your parade but the Cannondale Evo has a bottom bracket stiffness of 55N/mm, so that would be about the 130th stiffest bb.
They have a high stw ratio but that is a function of head tube stiffness and weight. The actual figure for the Cannondale Evo is 139Nm/deg/kg with the Cervelo coming in at 137 Nm/deg/kg.
So they are leaders in stw, but not by much.


No skin off my back...don't really care actually. But if you read my statement it is the stiffest THEY (ie..Velo) have ever tested.

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andy2
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by andy2

I'm sorry but I thought I was pointing out that thread is about BB stiffness not HT stiffness?

FBE uses different test jigs, they fix the head tube in the jig from my recollection, whereas the 91Nmm number was obtain with a THM Clavicula SP fork clamped at the hub.
They might also use a different method when weighing vertical and horizontal deflection data.
The number might be a value for horiz deflection only, etc.
EFBE are absolutely top quality tests but you can't compare them to Zedler numbers since the protocols are not standardized.
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