Velocite Carbon Frames Stiffness Data

In preparation for our new website launch we have been collecting quantitative data that we will share with customers.

Since the launch of Velocite, it has been our position to provide very stiff frames. Unfortunately, every bike company claims that they make stiff frames, thus our own claims about stiffness are not easily evaluated. Especially since we are not large enough yet to have our frames assessed by a third party, for example Tour Magazine.

We will of course approach them later this year and will hopefully gain the invaluable third party data and validation of our own efforts.

We collect stiffness data for our frames, stiffness being the most important parameter we consider, followed by weight and then finally cost. This is not what usually happens. Cost is normally, and prudently for large companies, the first and foremost consideration when developing a new frame model.

Sharing stiffness data and comparing it to another data set obtained in a different test setting, by different test administrators is actually bad science and something that should be avoided.

However I feel reasonably confident that our own test data is closely correlated to the data obtained by the EFBe method that is also used by the Tour Magazine (Head tube test, Bottom bracket test). Our test methodology is very similar due to our factory also producing frames for several German bike brands.

In essence, the frames are clamped by the dropouts and at the head tube while force is applied to the head tube for the head tube stiffness test, or to the bottom bracket for the bottom bracket stiffness test. Both tests actually measure the frame’s ability to resist torsion since torsion is the main force acting on the bike frame –  you can read more about this when our new website’s technology pages are online.

So without further ado, here are the Velocite stiffness numbers. Keep in mind that these are average numbers, and our performance targets. Individual frame stiffness may vary by up to +/- 5%.

Frame

BB N/mm

Head Tube N/deg.

Geos

120

80

Magnus

150

131

Helios Aero

150

96

Flux (MTB)

145

105

For comparison, here is a link to a blog that lists the data from one of the recent Tour tests: http://cozybeehive.blogspot.com/2010/01/bicycle-frame-stiffness-numbers.html

UPDATE: Here is the stiffness data normalized for weight and in absolute terms, as supplied in the updated release from Specialized here: http://www.bikeradar.com/road/news/article/specialized-mclaren-venge-aero-road-bike-launched-29642


HT N/deg/kg

Claimed weight (kg)

HT N/deg.

Specialized Venge 80 0.95 76
Specialized Venge McLaren 89.7 0.95 85
Felt AR1 56.4 1.1 62
Specialized Tarmac SL3* 124.3 0.88 109

*Tour Magazin test showed that a 0.9kg sample had HT stiffness of 116 N/deg., and BB stiffness of 65N/mm.

Please also keep in mind that our, EFBe and Tour data is not expressed in terms of stiffness to weight ratio, with units normally expressed as N/mm/kg, but in absolute stiffness numbers. Quoting stiffness to weight ratio is in my view misleading since the rider does not experience the ratio, they experience the absolute number. Stiffness to weight ratio is only useful when evaluating the raw material properties, for example when choosing the type of carbon fiber prepreg to use (although the more useful measure is FaW – fiber area weight)

Thus, assuming adequate correlation between our data and Tour’s data we can see that Magnus and Helios Aero have no peers, while Geos can stand proudly among the top of the range frames from our competitors.

This has been corroborated by our live testing and rider experience, so it is nice to be able to share this data with a good degree of confidence. Of course, as soon as we get third party test data we will make that available too.

  • An applicable quote from Sherlock Holmes books: "Data! Data! Data!" he cried impatiently. "I can't make bricks without clay" ;-D

  • Anonymous

    And what about the sister of the Helios ? I think it deserves it ! Regards

  • Selene will be sent to the factory next week to be tested on the same machine as the carbon frames. This way we will get completely reliable stiffness data for all our products.