[bdebde]

What vehicle?

I would go about 14T to start if its a standard truggy or buggy. Put ya close to 40mph, perfect for small track.

TRUGGY

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 14
Total Voltage: 14.8
Motor KV: 2200
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.006
Spur/Pinion Ratio: 3.29 : 1
Total Ratio: 14.12857 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Total Motor Speed: 32560 RPM
Vehicle Speed: 38.74 mph (62.22 km/h)

BUGGY

Differential Ratio: 3.3076923076923075
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 46
Pinion Tooth Count: 14
Total Voltage: 14.8
Motor KV: 2200
Tire Diameter (inches): 4.33
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.006
Spur/Pinion Ratio: 3.29 : 1
Total Ratio: 10.86813 : 1
Tire Circumference (inches): 13.6 inches (345.52 mm)
Total Motor Speed: 32560 RPM
Vehicle Speed: 38.59 mph (61.99 km/h)