November 16, 2025
Description
An asymmetrical chain guard ring for a Shimano front chainring with 42 teeth.
The chainring has 5 holes, but these are arranged asymmetrically.
All hole spacings are 86 mm, except for one which is 75 mm.
The bolt circle diameter is approximately 143 mm.
I assume that the asymmetry is due to the position of the crank.
The outer diameter of the guard is 185 mm. All necessary dimensions can also be found in the images.
I have also attached the Fusion3d file.
Printed in PET with supports on only on the bed. I used 10% infill.
License:
Creative Commons — Attribution — Noncommercial
11
Thomas
