New crank from Praxis Works

Discuss light weight issues concerning road bikes & parts.
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Ritterview
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by Ritterview

Praxis Works previewed a new crank at Interbike, with a new line, Turn. It is hard to tell from the Bicycle Retailer write-up if this crank is just OEM fodder, or of WW interest.


Bicycle Retailer wrote:
Turn looks to OEMs for crank sales

Praxis’ sister brand eyes 2014 spec

LAS VEGAS, NV (BRAIN) — Praxis, a fast-growing maker of cold-forged chainrings, is planning to enter the crank market with its Turn line. The company is tooling up to offer the road cranks for the 2014 model year and will meet with OEMs at November's Taichung Bike Week, a key show for OE spec.

Turn’s crank line includes a hollow-forged aluminum arm model and a carbon arm model. Both have the same 110mm bolt circle aluminum spider. Pricing is not final, but the company’s Jordan Kestler said they would be competitive with Shimano Ultegra and SRAM Force offerings.

The cranks will be available in three finishes and will come with Praxis-branded chainrings and bottom brackets. Currently the company is planning to make the cranks with 24mm spindles like SRAM’s GXP bearing system. It’s looking into making a 30mm spindle design, as well, Kestler said.

Kestler said since the company entered the chainring market, many customers have asked when they would offer a matching crank. The Turn brand will be used only for the arms, Praxis will remain the brand for chainrings, bottom brackets and bottom bracket conversion kits

Image

by Weenie


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djconnel
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by djconnel

So I suppose this is "the Turn crank".

24 mm spindles are going to get hammered on stiffness/weight testing. Spindle diameter is the #1 predictor of success on this, even more than material (carbon vs Al), in the Fairwheel tests.

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Ritterview
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by Ritterview

djconnel wrote:So I suppose this is "the Turn crank".

24 mm spindles are going to get hammered on stiffness/weight testing. Spindle diameter is the #1 predictor of success on this, even more than material (carbon vs Al), in the Fairwheel tests.


The Turn crank Praxis showed at Sea Otter 2011 bears little resemblance, and was noteworthy its non-spindly 35 mm spindles.


Image
Praxis uses a giant 35mm spindle for their prototype Turn road crank design
© James Huang/Future Publishing

Zigmeister
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by Zigmeister

djconnel wrote:So I suppose this is "the Turn crank".

24 mm spindles are going to get hammered on stiffness/weight testing. Spindle diameter is the #1 predictor of success on this, even more than material (carbon vs Al), in the Fairwheel tests.


Really? Because the Scott Foil with Bb86 pressfit 24mm bearings and cranks tests as one of the stffest setups tested.

Brandonnie
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by Brandonnie

wow looks nice hope its performance is as good as it looks!

mrfish
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by mrfish

Looks like another generic carbon crankset to me, designed to support sales of nice chainrings as a package, rather than bringing something new to the crank design space... I could be wrong, but my plan would be to make it as easy as possible for the installed base of Shimano, SRAM users to upgrade their crank to use my rings.

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djconnel
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by djconnel

Zigmeister wrote:
djconnel wrote:So I suppose this is "the Turn crank".

24 mm spindles are going to get hammered on stiffness/weight testing. Spindle diameter is the #1 predictor of success on this, even more than material (carbon vs Al), in the Fairwheel tests.


Really? Because the Scott Foil with Bb86 pressfit 24mm bearings and cranks tests as one of the stffest setups tested.


Stiffest bottom bracket or crank?

I was specifically referring to this test.

And missing this test, the crank with the widest spindle of all is the Look Zed:

Image

In this plot, the Campy, Dura-Ace, SRAM, and Stronglight, each with similar spindle diameter, are clustered. Then comes Zipp with a 30 mm axle. Then Look is at another level with its 50 mm spindle.

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

by topflightpro

djconnel wrote:So I suppose this is "the Turn crank".

24 mm spindles are going to get hammered on stiffness/weight testing. Spindle diameter is the #1 predictor of success on this, even more than material (carbon vs Al), in the Fairwheel tests.


This article seems to indicate that BB30 really doesn't improve stiffness that much: http://bikeresource.blogspot.com/2011/0 ... -bb30.html

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djconnel
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by djconnel

That's for the same spindle with different bearings.

Estelja
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by Estelja

Keep in mind the title of the BRAIN article, they are looking for OEM sales. These cranks are just a generic carrier on which to get their rings on bikes coming out of the factories. Their previously shown 35mm spindle crank would be more of an aftermarket item.

spud
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by spud

If I'm not mistaken, that test only measured deflection on the drive side crank when the chainring was constrained. They should also have tested non drive side deflection, as that would also take into account spindle wind up.

I have not tested anything, but I love BB30 and I wonder if part of the superior feeling comes from reduced system windup, which serves to keep the legs closer to 180 degree phasing.

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bura
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by bura

They should change their logo which is almost identical with Germany's SPIN.
http://www.spin-system.de/
Kuota Kom Evo
viewtopic.php?f=10&t=111825&p=955235#p955235" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
SOLD

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prendrefeu
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by prendrefeu

The name is too similar to Tern. :?

...and I like Tern. A lot.
Exp001 || Other projects in the works.

asv
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by asv

This image was posted on their Facebook page yesterday.

Image

by Weenie


gilesharrison
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Joined: Tue Nov 04, 2008 6:44 pm

by gilesharrison

Does no one think the carbon crank looks like the old Sram Red compact? They've not bought the tooling have they? Where's the standard BCD version - who's going to race on a compact?

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