Am I missing something?

[Gillico1]

Found this. https://www.radicalgolfcarts.com/ez-...7&c=217&i=1662
It's a 6:1. How fast would I be if I were at 22mph with 20.7 tires? Any safety tips for fast golf carts? That were only designed to go 12mph.

[Gillico1]

Originally Posted by kernal

LineXed? You mean the bed liner stuff? I don't think paint/body drag is a factor at 20mph.

Yeah when I refurbed the frame I took the body and top to the lineX place and had them spray it.

[Gillico1]

Originally Posted by rbuggies48IN

Did you contact PQ? What were their comments?

Just put the motor in Friday about 5pm so they were closed by then. I assume they did what they were supposed to since I did gain 3mph.

[JohnnieB]

Originally Posted by Gillico1

Found this. https://www.radicalgolfcarts.com/ez-...7&c=217&i=1662
It's a 6:1. How fast would I be if I were at 22mph with 20.7 tires? Any safety tips for fast golf carts? That were only designed to go 12mph.

It's better to make estimates based on empirical data.
You said you are getting 20MPH with a PQ motor at 48V on 17.5" tires and 12.44:1 gears, so the motor is maxing out at 4779 RPM. The 20MPH is a bit iffy because it was given in whole numbers, but it can be used for a rough estimate.

With the motor spinning at 4779 RPM, the cart will travel at 23.7 MPH on 20.7" tires.

If the gear ratio was changed to 8:1, the cart would travel at 36.8 MPH on 20.7" at 4779 RPM.

If the gear ratio was changed to 6:1, the cart would travel at 49.1 MPH on 20.7" at 4779 RPM.

However, in each case, the motor will not reach 4779 RPM because increasing the tire height and numerically lowering the gear ratio, increases the mechanical load on the motor, and the max RPM a motor will spin at for the voltage applied is the RPM at which the torque being generated equals the mechanical load.

To get a 25.0 MPH cart speed with 12.44:1 gears and 20.7" tires, you need the motor to spin at 5050 RPM. (Need a higher speed motor)

To get a 25.0 MPH cart speed with 8:1 gears and 20.7" tires, you need the motor to spin at 3248 RPM. (Need a high torque motor)

To get a 25.0 MPH cart speed with 6:1 gears and 20.7" tires, you need the motor to spin at 2436 RPM. (Need a very high torque motor)