How to Adjust the Throttle of Your Self-Propelled Lawn Mower

An orange lawnmower on grass.
What You'll Need
Wrench
Screw driver
Manufacturer instructions
Safety glasses
What You'll Need
Wrench
Screw driver
Manufacturer instructions
Safety glasses
For those homeowners who still mow their own grass and are fortunate enough to own a self-propelled lawnmower, it may be necessary to adjust the machine's throttle/traction from time to time. When it comes to self-propelled mowers, this can be crucial as you will either find yourself running to keep up with the mower, or moving as slow as molasses. Because the technique for throttle and/or traction adjustment will vary greatly between brands, models, and types of lawnmowers, the following steps will be basic and general in nature.
Many of today's non-commercial, self-propelled mowers lack a throttle control or adjustment and operate at one speed. The mowers are equipped with a bar affixed to the handle that you depress and hold to start and run the mower. Releasing the bar shuts down the lawnmower engine.
These types of self-propelled mowers also incorporate an additional bar affixed to the handle to engage and disengage the owner's drive train. It's possible to adjust the traction cable to increase or decrease the mower's response when you engage the drive train. However, adjusting the operating cable rarely, if ever, increases or decreases the speed of the motor.

The only real adjustment on these mowers is a bracket assembly used to secure both the operating and traction cables to the mower's handle. By loosening the bracket, you can slide the cables towards or away from the motor, which may increase or decrease the drive train traction and/or the throttle.

Step 1 - Release the Bracket

A lawnmower cutting grass with a close-up of the lawn.

Loosen the bracket that secures the mower's cable to its handle. The bracket will be affixed with a nut and bolt, screw, or knob.

Step 2 - Make the Move

Carefully adjust the cable or cables, about a 1/2-inch away from the engine to increase traction, or towards the engine to decrease traction and tighten the bracket.

Step 3 - Take a Test Drive

A lawn mower cutting a lawn.

Depress the starting bar and crank the engine. Slowly depress the drive train bar to test the mower's traction. If the mower is too fast or too slow, you may have to repeat the process numerous times until you achieve the desired response.

Safety

Always refer to the mower's owner manual before making adjustments and testing the mower. After adjusting the cables and before testing the mower for the first time, be prepared for an increased drive train response to avoid injury or property damage. Use extreme caution when operating a lawnmower. Keep hands and feet clear of the cutting deck at all times during operation to avoid severe injury. Wear the appropriate safety gear such as safety glasses, work boots, respirators, and work gloves when operating a lawnmower.

If you own one of these types of lawnmowers and are experiencing a rough or slow running motor, it usually indicates that it's time for service by a professional, small engine mechanic.