New frame testing data comparing top bikes (by Giant)

Discuss light weight issues concerning road bikes & parts.
quaman26
Posts: 72
Joined: Mon Apr 19, 2010 9:44 pm

by quaman26

Is there anywhere that I can find an english translation of the roadbike.de test articles ?

Epic-o
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Joined: Tue Nov 20, 2007 7:18 pm

by Epic-o

"The deflection at the bottom bracket is measured; the HIGHER the value, the STIFFER the frameset and better the pedaling efficiency"

"The deflection at the fork dropouts is measured; the HIGHER the value, the STIFFER the frameset."

No comments :roll: :roll:

topflightpro
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Joined: Tue Jan 13, 2009 2:35 am

by topflightpro

But if they used a 200g seatpost, the Giant wouldn't win.

tdudzik
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Joined: Sun Sep 02, 2012 2:17 am

by tdudzik

Tests make my S5 look like a bad, heavy choice... although it beats my 6.9 which was the bike i came from....

wingguy
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Joined: Thu Mar 08, 2012 11:43 pm

by wingguy

Epic-o wrote:"The deflection at the bottom bracket is measured; the HIGHER the value, the STIFFER the frameset and better the pedaling efficiency"

"The deflection at the fork dropouts is measured; the HIGHER the value, the STIFFER the frameset."

No comments :roll: :roll:


Um, yeah. Measured in N/degree and N/mm. So what's the problem?

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kgt
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Location: Athens, Greece

by kgt

It's a Giant test that proves Giant is the best frame. Normal...

Epic-o
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Joined: Tue Nov 20, 2007 7:18 pm

by Epic-o

wingguy wrote:Um, yeah. Measured in N/degree and N/mm. So what's the problem?


A deflection has units of length

Zigmeister
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Joined: Mon Jan 24, 2011 8:09 pm

by Zigmeister

Epic-o wrote:
wingguy wrote:Um, yeah. Measured in N/degree and N/mm. So what's the problem?


A deflection has units of length


Yes, I'm confused as well. What does 79 or 67 mean? If that is the force applied to the pedal in the rig, what is the measurement of deflection? Are they measuring how much it takes to deflect it 1mm?

I would have to assume the latter. At the 45 degree angle, the force that is required to deflect it 1mm is 79.x with the Evo for example? Thus, higher/more force is required measured in N/mm to move the frame at the measurement point 1mm? I'm unclear on this.

More marketing nonsense, and then they complain about being excluded from all other competitors testing, and fail to test the Scott Foil and Specialized Venge and some others. They said on their dime they bought all of these frames. Except they didn't buy all of the frames available as a comparison. In fact, we know the Scott Foil is stiffer than the Tarmac from a few other magazine tests. Unless my memory is failing me. Which would put the Foil up near/higher in BB stiffness of the Giant.

In the Velo mag review, they put 100lbs of force on the pedal and measured in mm the amount of deflection. This I comprehend...haha..I believe a few other tests I've read use the same method.

Epic-o
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Joined: Tue Nov 20, 2007 7:18 pm

by Epic-o

It's very simple actually but you have to call things by its name. Stiffness (N/m) should be maximized and Deflection (m) should be minimized. When you present a "technical" paper with that condescending shade, I don't expect those mistakes to be found.

Anyway, the concept of BB stiffness should be better explained (loads and boundary conditions) as a standarized testing protocol doesn't exist. Zedler shows 60-70 N/mm BB stifness values while Cervélo shows 200 N/mm BB stiffness values

Ravenstrife
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Joined: Mon Oct 24, 2011 3:34 am

by Ravenstrife

propaganda or not i find it funny that the Cannondale supersix beat the evo on both stiffness test (and won the pedalling stiffness test)

gabriel959
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Joined: Fri Jun 15, 2012 12:02 pm

by gabriel959

Ravenstrife wrote:propaganda or not i find it funny that the Cannondale supersix beat the evo on both stiffness test (and won the pedalling stiffness test)


Indeed, made me quite happy when I saw that :)

Even in the weight category you would be looking at a 1500 grams with a 200gr seat post.

mrfish
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Location: Near Horgen, Switzerland

by mrfish

Engineering truth heavily filtered by Marketing.

It fairly smashes brand attributes like transparency and honesty. If they can't compare their bikes with others in a fair way, then who is to say that they will behave differently when it comes to the quality of materials that go into the frame, or the quality of the after-sales service.

Simple response is not to buy this stuff.

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Tinea Pedis
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by Tinea Pedis

That's a ridiculous insinuation to make mrfish.

Which, given the amount of time Giant have been around for, you would think they would be well known if they behaved in that manner.


Show me an unbiased review done by a bike company? Unless you're figuring they're all crooks?

Ryan94
Posts: 71
Joined: Fri Jun 02, 2006 2:36 pm

by Ryan94

Dont forget they are testing a frame/fork system. Numbers are different between this test and other tests because Tour used a metal bar and tests just a frame. Giant is testing the frame/fork set.

MrFish: You have no clue of Giant as a company. The cycling industry would not be where they are today without them. Giant is:

1: The worlds largest bicycle company
2: The largest user of carbon in the industry
3: The only company that makes the carbon and resin vs. buying cheap prepreg sheets

topflightpro
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Joined: Tue Jan 13, 2009 2:35 am

by topflightpro

quaman26 wrote:Is there anywhere that I can find an english translation of the roadbike.de test articles ?


Open it up in Google Chrome. It gives you the option of having it translated to English. It actually comes out pretty good.

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