Why the larger pinion/spur versus smaller?

[GTSLOW]

So I have a used Wraith. It has a motor and spur gear but no pinion. The spur gear is a 56T 32P. I was thinking something like a 10 or 12T pinion?

My real question is why do people opt for gearing like a 80+ tooth spur and a 16+ tooth pinion when they could run a smaller spur and pinion?

84/16 = 5.25

56/10 = 5.6

Am I missing something here?

 

[Harley]

So I have a used Wraith. It has a motor and spur gear but no pinion. The spur gear is a 56T 32P. I was thinking something like a 10 or 12T pinion?

My real question is why do people opt for gearing like a 80+ tooth spur and a 16+ tooth pinion when they could run a smaller spur and pinion?

84/16 = 5.25

56/10 = 5.6

Am I missing something here?

If someone is using an 80+ tooth spur than it is 48p. You have a 32p spur. The overall size is not smaller, just the tooth count.

 

[GTSLOW]

So the smaller setup is OK if 32 pitch and the larger setups are for 48 pitch? I take it the 32P teeth are stronger?

Sorry if these are stupid questions. I really do have no clue.

 

[Sneetches]

Yes 32P is more beefy. Here is a comparison of gears for the Wraith exactly like you're asking. 32p is on the right, 48p is left. People switch to 32p on the basis of stripping 48p gears with too much power.

 

[Olle P]

My real question is why do people opt for gearing like a 80+ tooth spur and a 16+ tooth pinion when they could run a smaller spur and pinion?

I think the primary reason is that 48P is what the rig is equipped with when purchased.

* From an engineering point of view I'd stay away from gears with less than 12 teeth since these don't run smooth enough and wears down too fast.
* I'd also avoid using gears with very small teeth, like 64P, since these are inherently weak and it's difficult to get a proper gear mesh.
* From a financial point of view I'd stick to standard pitches instead of defining a different size and shape of cogs. Personally I use 48P as much as possible since I have bought a broad selection of 48P pinions.