1/5 spur bore


I'm on one today
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Good morning, can anyone give me the bore size of their 1/5 spur? Specifically these double flat bores as seen on this HR one:

I appreciate the info!

I have a 10mm shaft off a 1/5 scale I'm trying to find/get/convert new gears to. It has the same double flat as this.
Oh wait a second. That is the Spur gear, not the pinion.

Hold please...
That goes on the Arrma 8S BLX Gearbox Input Shaft (ARA310922). There are two bearings, the inner one and the outer one.


The outer one ARA610016 is 8x16x5mm with an 8mm inside diameter. So I would "assume", by looking at the drawing the inside diameter of the spur gear is also 8mm.
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