Left Crank Arms
#1
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Thread Starter
Left Crank Arms
Needed to replace a 170 mm one on one of my bikes with the square taper hole, the new parts square hole, is clocked a few degrees off from the original one. I did not notice it when I ordered it, and was unaware there was 2 different types. What do they designate these as so I can be sure to order the correct one?
Thanks.
Thanks.
#2
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There are 2 orientations, diamond and square:
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A 'few degrees off' would be the worn out, 'inside' part of the square taper hole. They're either as above, diamond or square.
#4
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Thanks, I got the "diamond" I needed the "square". On a side note, why do the manufacturers male 2 types? They're actually 45 deg. off.
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Note there may be some differences in the "Q-Factor" of the cranks, or the width at the pedals. MTB arms will splay out more than Road arms. Vintage arms can be very straight.
Vintage Campagnolo, Stronglight, and TA could be different from the Asian brands.
But, largely the arms are interchangeable.
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#6
Rhapsodic Laviathan
i actually didn't know that about square taper
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I did know this, or should say learned this, as we replaced quite a few NDS crank arms that were damaged or bent. We now keep the spare left cranks sorted by the orientation.
I try and learn something new everyday.
I try and learn something new everyday.
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www.TheBikeMenOfFlaglerCounty.com