Page 1 of 1

Frame stiffness numbers

Posted: Tue Nov 09, 2010 4:30 am
by elviento
I apologize if these have been posted before but a search failed to pull any up. SO here it goes: has anyone posted frame stiffness numbers of major brands/models, i.e., how much deflection of various parts of a frame under XXX kg load?

Thanks!

Re: Frame stiffness numbers

Posted: Tue Nov 09, 2010 8:15 am
by kgt

Re: Frame stiffness numbers

Posted: Tue Nov 09, 2010 8:42 pm
by Martin1977
I was able to translate just several simple words and as i do not speak Italian, could anyone explain me what is the difference in between test protokol of this italian magazine and for exemple german Tour? In Tour, for example Cervelo R3sl and Scott were always one of the best frames in stiffness data, but here it seems, that Cervelo and Scott are not any better than other frames. In fact, it seems, that they are more (just little) flexy in BB than others.

translating it word by word in translator would be too much time consuming for me.

Martin

Re: Frame stiffness numbers

Posted: Tue Nov 09, 2010 11:17 pm
by Mario Jr.
That's also the results "Tour" finds. Medium to good BB stiffness, but not at all test winning. They excel in STW values, as they are quite light.

Re: Frame stiffness numbers

Posted: Wed Nov 10, 2010 8:59 pm
by mass
There are two graphs referring to tests with a 80kg cyclist.

The top one is for when the bike is in motion while pedaling. Y axis is deformation in mm. X axis has 5 sections: constant speed, accelerating, climbing, sprinting. The red line is for the bottom bracket laterally, blue line is the seat post, and the green line (not sure) angle of head tube in gradients?

The second graph is while braking. Y axis is deformation in mm. X axis: normal braking, abrupt stop, impact. The blue line is the seat post, purple bottom bracket vertically, and black the fork.

Re: Frame stiffness numbers

Posted: Wed Nov 10, 2010 9:18 pm
by mass
Martin1977 wrote:I was able to translate just several simple words and as i do not speak Italian, could anyone explain me what is the difference in between test protokol of this italian magazine and for exemple german Tour? In Tour, for example Cervelo R3sl and Scott were always one of the best frames in stiffness data, but here it seems, that Cervelo and Scott are not any better than other frames. In fact, it seems, that they are more (just little) flexy in BB than others.

translating it word by word in translator would be too much time consuming for me.

Martin


The article rates both those frames as very stiff. It mentions that the slope of the red line is near constant while sprinting.

Re: Frame stiffness numbers

Posted: Mon Apr 09, 2012 6:54 pm
by phourgenres
Awesome link and translation, thanks!