Hight tooth-count steel spur gear for RS4 Sport 3
#1
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I have scoured the internet, and while I've been able to find a hardened steel 66T spur gear (SpeedTek RC) for the RS4 Sport 3, I cannot for the life of me find one that would stand in place of the plastic 75T one HPI makes for this model. I have been looking at other 70-90T, 48 pitch steel gears made for non-HPI 1/10th models, and while I've come close (Hot Racing SECT881)-- I haven't found anything yet that seems 'close enough to work'. Posting here with the hopes that I am not the only one who has ever embarked on a quest for this steel part, to see if anyone has been able to make something for a different car work.
By my calipers, these seem to be the dimensions of the official HPI, plastic 75T:
By my calipers, these seem to be the dimensions of the official HPI, plastic 75T:
- 9.5mm inner shaft hole diameter
- 41mm gear outer diameter
- 5mm thick
- 4 x 3mm screw holes, spaced 10.5mm apart from one another
Last edited by 7h3C47; 04-19-2023 at 09:22 AM.