Shaving material off my 105 crankset

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Skorp
Shop Wrench
Posts: 90
Joined: Thu May 30, 2013 12:54 am

by Skorp

Hello

Image
I have a awful looking 105 crankset and i would like to change the looks to the better.
I was thinking to grind off the edges and smoothing them out making the crank easier on the eye.

This requires me to remove around 2mm of material on the edges. Do you think this will affect strengt much?
I will also change the chainrings to a simpler lighter type.

N3xus989
Posts: 9
Joined: Wed Nov 05, 2014 1:51 pm

by N3xus989

I guess it depends how heavy you are to affect the stiffness of the cranks. But I guess 2mm wont be that significant. Would recommend grinding slowly, take it for a test ride before grinding again. Would be interested to see how you plan to grind it off :D

by Weenie


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eric
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Joined: Tue Nov 11, 2003 9:47 pm
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by eric

This is a bad idea with hollow cranks. You don't know how thick the walls are.

A used set of 7800 cranks would be smarter.

Skorp
Shop Wrench
Posts: 90
Joined: Thu May 30, 2013 12:54 am

by Skorp

yeah, i did some measurements, its way more than 2mm that needs to be removed for the looks i want. Even then im not sure if it will be good looking.
With new chainrings, the molested 105 cranks would be more expensive than a nicer looking set. I will sell the 105 crank, and is currently bidding on a Truvative Elita V1 crankset which looks more classic.

eric
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by eric

How did you measure the wall thickness of the hollow crank arm without cutting it in half? X-rays?

bm0p700f
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by bm0p700f

superman eyes eric.

Skorp
Shop Wrench
Posts: 90
Joined: Thu May 30, 2013 12:54 am

by Skorp

i don't know the wall thickness. My guess is that these edges are there because of design, and not strenght.
Altough, the grinding i planned will be too much for my comfort. I won't compromize safety, so a new better looking crankset is bought.

jeffy
Posts: 1325
Joined: Sun Oct 05, 2014 11:51 pm

by jeffy

will be interested to see how this develops

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hjb1000
Posts: 265
Joined: Wed Sep 16, 2009 10:25 am
Location: Australia

by hjb1000

For reference, this is what an XT hollowtech crank looks like in section:

Image

davidalone
Posts: 622
Joined: Fri Feb 10, 2012 4:27 pm

by davidalone

would be pretty simple to get an idea of reduction in stiffness. just find the polar moment of area change.

odin99
Posts: 157
Joined: Wed Feb 16, 2011 7:46 pm

by odin99

get a 7800 crankset...

totoboa
Posts: 88
Joined: Thu Dec 13, 2012 4:24 am
Location: Sierra Foothills, California USA

by totoboa

Are Tiagra also Hollowtech ? - thanks

mattr
Posts: 4671
Joined: Fri May 25, 2007 6:43 pm
Location: The Grim North.

by mattr

Pretty sure tiagra is solid. It used to be 105 where the hollow cranks started.

by Weenie


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