When I worked at a shop we used to do this a lot when fitting 135mm hubs into 130mm frames. The width of the spacer can vary a lot between models and any bike shop should have a good inventory of these spacers. You just need to keep in mind that if you remove to much from the right side you may not have enough clearance between the frame and the last cog of the freewheel.I'm building a custom bike for my kid, and want to reduce the width of a rear hub. On the rear hub shown below, can I remove/modify the spacer on the right hand side to reduce the width? Assuming yes, any idea how wide these spacers typically are?
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