To start, there is no such thing as “optimal stiffness” and there is no circumstance where a torsionally flexible frame offers any advantage to the rider. Our goal is to make torsionally the stiffest frames in any category where we have products.
We will explain the above statements in greater detail over time by using data, charts and third party studies, not in house data and not other bicycle manufacturers’ data. If we do generate our own data if will be to add to the body of knowledge and we will publish it in a format of a scientific study detailing the hypothesis, the experimental method and our conclusions.
How is the stiffness data collected? Here is a good overview of an industry standard testing protocol as used by Tour Magazin in Germany: How Tour Tests
Tour testing protocol is of course not to everyone’s liking so you will find stiffness protocols used by Specialized, Giant and VeloNews all giving somewhat different results. I mention these three in particular as their results can be found online. The advantage of Tour testing is that they are mostly independent and they publish a lot of data. It is otherwise very difficult to find any empirical (measured) numerical results for most bikes in the market.
The last advantage of the Tour testing method is that we use it too thus even though Tour has not reviewed our bikes yet since we have no presence in the German market, our results were obtained by applying the same testing methodology.
We compiled the following results using the published and publicly available data from Cannondale and Tour Magazin.
Torsional Stiffness N/deg
|Trek Madone 6 SSL||88|
|Cervelo R3 SL||94|
|Giant TCR Advanced SL (ISP)||95|
|Cervelo R5 CA||97|
|Cannondale Super Six EVO||99|
|Velocite Selene (alloy)||105|
|Giant TCR Advanced SL LTD||108|
|Specialized Tarmac SL3||112|
What is clear is that the Velocite Magnus is in a league of its own, achieving torsional stiffness almost 20% greater than the next best frame. This was not achieved by using an inordinate amount of carbon fiber as the Magnus weight starts at 980g, painted.
How we achieve this and the great results for the Velocite Geos and the Velocite Selene is a topic for future posts.
Once we verify our torsional stiffness results as measured at the bottom bracket (also known as pedalling stiffness, lateral stiffness (incorrectly) and BB stiffness) we’ll publish that data too. The reason we are not publishing the results now is that our numbers show almost 100% greater torsional stiffness at the bottom bracket than the next best comparator. Yes, the Magnus is seemingly twice as stiff.
We will instead leave you with an image and a video from the 2013 Taipei Cycle Show that was held last week. We brought a Magnus frame and invited people to stand on its rear triangle. Yes, stand on it. The heaviest person that we had on it was 87kg.
We also took a video showing an 85kg Velocite staffer climbing onto the frame and (gently) bouncing on it. Try this with any other frame.
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There is an opinion that chainstay and rear triangle stiffness do not matter. We even had a prominent European brand’s brand manager tell us that “there is a hub in there!”. Well yes there is normally a hub between the rear dropouts, but it is not as simple to rig up the proper test apparatus such as we have in the factory. There is also no detriment to having super stiff chain stays in terms of comfort, and there is no chatter or loss of grip in corners and under acceleration.
The Magnus is our most popular frame and we’ll soon release the 3rd generation version that remains true to its stiffest road frame on the planet heritage.