Range difference street vs "off road"

[EzGoRN]

Cart is question is the once in my sig. Just wondering what kind of range difference there would be with 20.5" tall street tires inflated to 35 psi vs 23" off road tires inflated to 12 psi.

Anybody have a ballpark guestimate?

[NCPW]

Couldn't tell you the exact number/distance difference and speaking on just tires and nothing else, the 20.5" street tires would give better range.

Factors that would help range using the 20.5" tires would be less rotational torque (i.e. amps) needed to move them and higher PSI rolls easier and knobby, low pressure off-road tires.

[EzGoRN]

I'm curious about this as I have been considering purchasing a set of street tires. Wondering if it would be worth it.

[kgsc]

If the tread change is drastic you would notice a difference but the terrain will make the biggest difference. I have always thought that the more noise a tire makes the less efficient it is.

[JohnnieB]

Unfortunately, you failed to identify your cart's drive type in your signature block. A SepEx drive, which was called a PDS (Precision Drive System) in 2005, intrinsically has a better range than a series drive system.

That aside since the specific questions are tire related:

Tire height: The taller the tire the less linear force available where rubber meets road and more torque is needed to rotate tire. That is a double whammy on range.

Tire inflation pressure: Underinflated and low pressure tires have a higher rolling resistance, so more amps are needed to travel same distance.

Tire tread: As kgsc mentioned, the noisier the tire, the greater the rolling resistance.

In a nutshell, a smaller diameter, higher inflation pressure tire with a non-aggressive tread will yield better range.

As with most things related to carts, the optimal tire is a compromise somewhere between the extremes of each of the above factors. And there is a point of diminishing return going towards each extreme in these factors.

If the tire is too small, the motor will exceed the max recommended RPM before the cart reaches the desired MPH.

The higher the tire's inflation pressure, the harsher the ride.

The most efficient tread pattern is a straight one, akin those found on wheelbarrows, but they lack traction.

Bottom line: Based on effective torque losses caused by tire height alone, I suspect you might get up to about 10% better range with the 20.5" street tire.

[EzGoRN]

Originally Posted by JohnnieB

Unfortunately, you failed to identify your cart's drive type in your signature block. A SepEx drive, which was called a PDS (Precision Drive System) in 2005, intrinsically has a better range than a series drive system.

That aside since the specific questions are tire related:

Tire height: The taller the tire the less linear force available where rubber meets road and more torque is needed to rotate tire. That is a double whammy on range.

Tire inflation pressure: Underinflated and low pressure tires have a higher rolling resistance, so more amps are needed to travel same distance.

Tire tread: As kgsc mentioned, the noisier the tire, the greater the rolling resistance.

In a nutshell, a smaller diameter, higher inflation pressure tire with a non-aggressive tread will yield better range.

As with most things related to carts, the optimal tire is a compromise somewhere between the extremes of each of the above factors. And there is a point of diminishing return going towards each extreme in these factors.

If the tire is too small, the motor will exceed the max recommended RPM before the cart reaches the desired MPH.

The higher the tire's inflation pressure, the harsher the ride.

The most efficient tread pattern is a straight one, akin those found on wheelbarrows, but they lack traction.

Bottom line: Based on effective torque losses caused by tire height alone, I suspect you might get up to about 10% better range with the 20.5" street tire.

Much appreciated! Updated the sig as my cart has PDS drive system. 10% would almost make it worthwhile if the price on the tires was right. I have seen Loadstar tires marketed as golf cart tires, but aren't those trailer tires?? Seems as though that might ride rough.

[BobBoyce]

Originally Posted by EzGoRN

Much appreciated! Updated the sig as my cart has PDS drive system. 10% would almost make it worthwhile if the price on the tires was right. I have seen Loadstar tires marketed as golf cart tires, but aren't those trailer tires?? Seems as though that might ride rough.

I buy Carlisle "Sports Trail" tires on 12" wheels from WalMart. I use them on the highways and interstates when I'm towing carts. They also work good for on-road and off-road use around here. I tend to use 2 sizes... 4.80-12 (19.5") for the fronts, and 5.30-12 (20.5") for the rears. They are not expensive, under $60 each. Most stores have a choice of white painted wheels, or galvanized steel wheels for a bit more.

They tend to carry both 4 lug and 5 lug types, be sure to get the right ones for your cart. They are high pressure type tires, so very low rolling resistance. With an RXVs motor removed for towing, I've towed at up to 70 MPH with these tires with no issues. I felt the rear end afterwards and not even warm.