Talk some sense in me in regards to gearing

[knucklebusta]

I'm wondering this. Why would a 17T pinion with a 92T spur cause less heat on the motor than a 21T pinion with the 92T spur?

It would seem to me that the 21T would have less rpms to spin the spur than the 17T.

So the 17T would produce more RPM's in the motor, correct? So wouldn't this make the motor run more hot as it's spinning more?

I don't get it. Any help is appreciated.


Why I'm wondering this is my xxx-4 has a SS 5800 in it. The shop I bought it at recommended a 20 or 21T pinion. This which I didn't realize until I thermalled the unit once was making the motor as hot as the sun. When it thermalled, there was an electronic burning smell. Is this normal?

Now someone on another forum recommended that the 20/21T spur was way too much for the motor and recomended a 17T. I couldn't find a 17T so I got an 18T but the motor is still too hot to touch after running for 5 mintues or so.


Any ideas?

Thanks, Kevin

[SS Pede]

The 21 tooth would in effect have less RPM's, but that's because it requires more torque to keep it turning than with a 17 tooth pinion. Imagine riding a bike. If you're in a high (hard to pedal) gear, you don't have to pedal as fast to go a given speed. But it's a lot harder to accelerate up to that speed if you stay in a high gear! It takes less energy to be pedaling faster but with less effort per pedal stroke.

[knucklebusta]

The 21 tooth would in effect have less RPM's, but that's because it requires more torque to keep it turning than with a 17 tooth pinion. Imagine riding a bike. If you're in a high (hard to pedal) gear, you don't have to pedal as fast to go a given speed. But it's a lot harder to accelerate up to that speed if you stay in a high gear! It takes less energy to be pedaling faster but with less effort per pedal stroke.

That's what I thought, thanks for the clarification and analogy.

Kevin

[danhfvcsd]

Smaller Pinion Tooth Count = Faster Acceleration = Less Heat (generally)
Larger Pinion Tooth Count = Higher Top Speed = More Heat (generally)

Smaller Spur Tooth Count = Higher Top Speed = More Heat (generally)
Larger Spur Tooth Count = Faster Acceleration = Less Heat (generally)


Another lil thing - the motor doesn't have to turn as much mass with a smaller pinion...can someone fill the rest in there? - i've confused myself -lol-