Golf Cart Tire Size vs. Torque: The 23-Inch Efficiency Tax
Installing 23-inch tires increases speed but kills torque. Learn the physics of mechanical leverage and how larger tires affect your motor's efficiency and heat levels.
- In the Research Lab, we compare this to using a wrench to loosen a stuck bolt.
- Based on our testing with a standard 48V DC motor, here is how the math breaks down when moving from stock to oversized tires.
- Electric motors are most efficient when spinning at high RPMs with low resistance.
A 6-inch lift kit plus 23-inch tires transforms a "grandpa cart" into an off-road beast. While the top-speed increase is immediate, the impact on your motor's efficiency is often misunderstood. It's like using a longer wrench: you have more reach, but it requires significantly more effort at the handle.
How Big Tires Re-Gear Your Cart
In the Research Lab, we compare this to using a wrench to loosen a stuck bolt. A stock 18″ tire is short and easy to turn. A 23″ tire is a long breaker bar; you have more reach, but it takes massive Amperage at the motor to get that first movement.
- Stock Tires (18″): Provide the factory-intended balance of torque and speed.
- Large Tires (23″): Increase the distance traveled per motor revolution, but require ~28% more force to rotate.
By bolting on 23-inch tires, you have effectively “re-geared” your cart for high speed, even if you never touched the transaxle. The motor now has to work 28% harder just to move the same weight.
This is the exact trap owners of E-Z-GO TXT and Club Car Precedent carts from the 2010s fall into when they add a 6 inch A-arm lift and 23×10-14 tires for the look. The stock transaxle on those cars is geared around 12.5:1 to suit an 18 inch tire, so throwing on a 23 inch tire without a gear change effectively lowers your numeric ratio and moves the whole powerband into a range the motor was never wound for. A useful rule of thumb: every inch of added tire diameter shifts your effective gearing by roughly 5 to 6 percent. Go from 18 to 23 inches and you have re-geared the car by close to 28 percent, which is why the low-end grunt vanishes and the motor spends far longer clawing through its high-amperage startup phase.
The Speed-For-Torque Trade Table
Based on our testing with a standard 48V DC motor, here is how the math breaks down when moving from stock to oversized tires.
Read the table as a warning label, not a menu. The speed gains in the left columns are the numbers sellers advertise; the torque loss and heat rise on the right are the bill that comes due later. A stock 48V car that already labored with four adults on a grade will not merely feel slower on 23 inch tires, it can trip its controller into thermal cutback or stall outright halfway up. Note how the motor temperature rise accelerates faster than the speed gain: at 23 inches you buy 28 percent more top speed but pay with a 40 percent hotter hill climb. That nonlinear heat curve is the real reason big tires kill motors, and it is why the recommendations in section four are not optional if you drive anywhere but flat pavement.
| Tire Diameter | Top Speed Gain | Effective Torque | Motor Temp Rise (Hill Climb) |
|---|---|---|---|
| 18″ (Stock) | Baseline | 100% | Normal |
| 20″ (Mid-Size) | +11% | 89% | +10% |
| 22″ (Large) | +22% | 78% | +25% |
| 23″ (X-Large) | +28% | 72% | +40% |
The Verdict: You gain roughly 4 to 6 MPH in top speed, but you lose nearly 30% of your hill-climbing torque. If your cart struggled with four passengers on a hill before, it will likely stall now.
Where The Lost Energy Becomes Heat
Electric motors are most efficient when spinning at high RPMs with low resistance. Large tires create the opposite environment: Low RPM with High Resistance.
This forces the motor to stay in its “High Amp Draw” phase for much longer. That extra amperage doesn’t all turn into movement; a large portion of it turns into Heat. In our tests, 23-inch tires caused the motor casing to hit “Critical” temperatures (200°F+) twice as fast as stock tires during stop-and-go driving.
The danger with heat is that it compounds. A hot motor has higher winding resistance, which draws still more amperage to make the same torque, which produces still more heat, a runaway loop that ends in a scorched armature or a melted commutator. On sealed carts you rarely see the temperature climbing until you smell hot varnish. Series-wound motors tolerate this abuse a little better than Sepex units, but neither is happy living in its stall region. If you must run big tires, plan your driving so the motor gets a chance to spin up and cool between hills, and treat any burnt-electrical smell or sudden power fade as the motor telling you it is cooking. A $30 infrared thermometer aimed at the motor case after a hilly loop is the cheapest insurance you can buy.
Upgrades That Offset The Penalty
If you are committed to the 23-inch tire look, the Research Lab suggests these compensatory upgrades to protect your motor:
- High-Amp Controller (400A-500A): To provide the extra “burst” needed to overcome the mechanical disadvantage.
- 2-Gauge Cables: To handle the increased amperage without melting your battery terminals.
- High-Torque Motor: If you live in a hilly area, a motor wound for torque (Series or high-torque Sepex) is a requirement for 23-inch tires.
One under-appreciated compensator is simply choosing a lighter tire and wheel package. A steel 14 inch wheel wrapped in a heavy 23 inch mud tire adds a lot of rotational mass, and rotational mass hurts acceleration far more than static weight because the motor has to spin it up every launch. Swapping to a lighter aluminum wheel of the same diameter can recover a noticeable slice of the low-end response you lost. Finally, if outright hill performance matters more than the lifted look, consider stopping at 20 or 22 inch tires; the table shows they cost far less torque and heat than the jump to 23 inches while still giving you meaningful ground clearance and a speed bump.
For the federal equipment standards that apply, see NHTSA low-speed vehicle standards.
Frequently Asked Questions
How much torque do I lose with 23 inch tires?
Mathematically, moving from an 18-inch stock tire to a 23-inch tire results in a torque loss of approximately 28%. This makes the cart feel more sluggish during takeoff and significantly reduces its ability to climb steep hills.
Will bigger tires burn out my stock motor?
Larger tires put a significantly higher load on the motor, leading to increased heat. While it may not happen immediately, sustained use of 23-inch tires on a stock motor, especially with heavy loads or on hills, can eventually lead to the motor windings burning out due to excessive heat.
Can I get my torque back after installing big tires?
Yes. To recover lost torque, you can upgrade your motor controller to a higher amperage (400A+), install a high-torque aftermarket motor, or change the internal transaxle gears to a higher ratio.
Reviewed and updated July 10, 2026 by the Golf Cart Lab team.
