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I need to vent for a moment. I've spent way too much time lately looking for 0.8mod pinions for use in Tamiya and Kyosho vintage cars. Seems most manufacturers group 0.8mod with 32p calling them "the same". They are close. Very close in fact, but THEY ARE NOT EXACTLY THE SAME. And when you are talking about mechanical tolerances measured in 0.1mm variances, it makes a difference. You can have PERFECT gear mesh between the pinion and spur, but if they are not the exact same gear pitch, you will have extra noise and extra wear compared to when both gears are the exact same pitch. 32p = 0.7938mod 0.8mod = 31.75p Practically speaking, DOES THIS MATTER? For the most part, no it doesn't. You can use 32p pinions with 0.8mod spurs and not have any trouble. Many, many people will attest to this, including racers that really push their cars. I'm sure there will be replies this post confirming that using 32p with 0.8mod spurs is perfectly fine. But, if you categorize yourself as a perfectionist, anal, or autistic, it will bother you that you are mixing 32p with 0.8mod. It bothers me. I won't say which category I fall into. I wish manufacturers were honest and factual when representing their products. If the pinion is machined as 32p, say so. It if is machined as 0.8mod, say so. Do not say 32p/0.8mod. It is false advertising. The math proves this. It cannot be both at the same time. The machining setup required to grind the gear teeth is different between 32p and 0.8mod. It is one, or the other. From my research it looks like the choices for true 0.8mod pinions for 1/8" shaft motors are few and far between: You can buy the butter-soft Tamiya aluminum stock pinions. Too many to list, but they are cheap at least. But you risk stripping out the spur once the pinion has worn down enough. If you keep track of wear, you can avoid spur damage in most cases. These do not last very long as most of us on this forum know. That's why switching to a steel pinion is one of the most common recommendations to make to someone that asks "I'm about to build ______. What hop-ups should I add to my car?" You can buy the Tamiya steel pinions: Tamiya 54628 Steel Pinion 17T 0.8mod Tamiya 54629 Steel Pinion 19T 0.8mod But as you can see, there are only 17T and 19T choices. You can buy Kyosho vintage pinions: W-5009 - Hard Pinion 9T 0.8mod W-5010 - Hard Pinion 10T 0.8mod W-5011 - Hard Pinion 11T 0.8mod OT-23 - Aluminum Pinion 12T 0.8mod OT-50 - Aluminum Pinion 13T 0.8mod OT-51 - Aluminum Pinion 14T 0.8mod OT-24 - Aluminum Pinion 15T 0.8mod OT-52 - Aluminum Pinion 16T 0.8mod OT-53 - Aluminum Pinion 17T 0.8mod UM-24 - Aluminum Pinion 19T 0.8mod Since these are vintage, they are usually a bit more expensive and harder to find. And the aluminum ones are butter-soft like Tamiya stock so you don't want them anyway. You can buy the Carson steel pinions: 500013400 - Steel Pinion 10T 0.8mod 500013401 - Steel Pinion 11T 0.8mod 500013403 - Steel Pinion 13T 0.8mod 500013439 - Steel Pinion 14T 0.8mod <--- Yes, part # is correct. 500013404 appears to be some Audi Quattro S1 1/10 scale body. 500013405 - Steel Pinion 15T 0.8mod 500013406 - Steel Pinion 16T 0.8mod 500013407 - Steel Pinion 17T 0.8mod 500013408 - Steel Pinion 18T 0.8mod 500013409 - Steel Pinion 19T 0.8mod For 5mm motor shafts, Robinson Racing makes some high carbon steel 0.8mod pinions. Their website is broken, so you can't see the part numbers for them and I don't care enough to look it up somewhere else because I don't use 5mm motor shafts. So far I have not been successful in finding any Chinese manufacturers of 0.8mod pinions for 1/8" motor shafts. I've just placed a ridiculous order ($$$) with Tony's Tamiya Parts for Carson 0.8mod pinions because there is literally no other choice, which is rather frustrating. I live in the USA, so Carson is generally not available here except through sellers like Tony's. Thanks for listening to my rant. I feel a little bit better.