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Crank arm good to go or do not ride?

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Crank arm good to go or do not ride?

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Old 08-12-18, 06:25 PM
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REDMASTA
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Crank arm good to go or do not ride?


Recently purchased a used square taper crankset, didnít realize from the photos that the nds crank arm has what appears to be damage from screwing the crank puller in too far.

You can see the grooves the puller created in the taper which go right up to the indentation left from the bottom bracket spindle.



Before installing and riding this crankset should I be concerned about any problems down the road or is it a non issue?

Thanks!

Last edited by REDMASTA; 08-13-18 at 10:46 AM.
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Old 08-12-18, 07:11 PM
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That damage would not concern me.
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Old 08-12-18, 07:15 PM
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If there is a burr I would file it down and install
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Old 08-12-18, 07:41 PM
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No biggie.
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Old 08-12-18, 07:52 PM
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Originally Posted by trailangel View Post
If there is a burr I would file it down and install
Me too, but be careful not to file anywhere but the outer edge near the damage.
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Old 08-12-18, 09:02 PM
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No problems there. Install it, ride, and forget about it.
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Old 08-12-18, 09:14 PM
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I suspect the "damage" you see is from the retaining bolt being tightened down, does the bolt/nut have serrations on it's mating face? To tighten an extractor so tight as to have gouged the arm is pretty unlikely. Possible? Yes but not common at all. If I saw a mechanic tightening an extractor this tight I would have a talk with him about who will pay for the arm when he has stripped out the threads before the extractor even began it's job. When the extractor is in use the force it applies on the arm is outward. This kind of "damage" shown is from a compressive force and a lot of it. Andy
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Old 08-12-18, 09:18 PM
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Extractor treads looks OK to remove it, if it it's not up to your expectations.
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Old 08-13-18, 07:18 AM
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The crank bolts are smooth and flat on the back itís definitely from a crank puller. Must of used a tool similar to the Park which is what I use as well. If one were careless and kept wrenching away at it the threaded portion of the tool would push into the taper.



Thank you for the replies, seems the consensus is that it should be fine. Didnít want to cause a fuss with the seller if itís only cosmetic. Will install and ride
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Old 08-13-18, 08:35 AM
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Originally Posted by AlmostTrick View Post
Me too, but be careful not to file anywhere but the outer edge near the damage.
+1

If it was steel, you could use a small riffler file or a stone. Al can blind smooth files and stones and sandpaper. You might use some 220 grit sandpaper wrapped around a dowel to gently remove the burr.

But the damage is not structural (it won't affect cycling performance).
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Old 08-13-18, 10:44 AM
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The crank arm is aluminum. Added another photo since itís hard to get a good angle but the gouges go a few mm into the taper, right up to where the spindle will be when pressed onto the bottom bracket. Thanks for the suggestions, might carefully remove any burrs, donít want to accidentally make it worse if its only cosmetic, was mainly concerned it was structural.

Last edited by REDMASTA; 08-13-18 at 10:48 AM.
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