PXi Series™ Engines

PXi Series™ Engines

Professional features. Homeowner friendly.

Maximize the performance of your equipment with our top-of-the-line PXi Series push mower engines. They’re the most powerful we offer and include professional-grade components to handle the toughest jobs, season after season. Our ReadyStart® starting technology for easy, 1-step starting comes standard, and you can enhance your mowing experience with our optional lithium-ion electric start, or our noise-reducing technology that’s up to 50% quieter.

8.5 - 10.00

Gross Torque (ft-lbs)

190 - 223cc

Displacement

Gas

Engine Fuel

ReadyStart®

Starter

Features

Made in the USA

Made in the USA of US and global parts.

ReadyStart® Starting Technology

No prime, no choke; just pull for power.

Dual-Sealing Commercial-Grade Air Management System

Reduces harmful yard debris.

Qualified 60% Longer Engine Life***

InStart® (Optional)

Skip pulling the rope and get right to work with our lithium-ion battery electric starting technology. Effortless starting, every time - just push the button and go.

Quiet Power Technology® (Optional)

Don't worry about bothering the neighbors with a 50% quieter mowing experience**.

* See https://www.briggsandstratton.com/na/en_us/support/starting-promise.html for complete details.
**Only available on 7.75 and 8.75 models.
***Available only on 8.50, 10.00 models when compared to the expected life of a standard Briggs & Stratton® E Series engine.

Specs

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Torque (ft-lbs, gross)*
10
Engine Displacement (cc)
223
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
15.8
Width (in)
13.4
Height (in)
10.1
Weight (lbs)
31
Bore (in)
2.91
Stroke (in)
2.04
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
0.3
Oil Capacity (oz)
18
Lubrication System
Dura-Lube Splash Lubrication
Oil Filter
Optional
Starter
ReadyStart®
Air Filter
Dual-Sealing Commercial-Grade Air Cleaner
Muffler
Super Lo-Tone™
Fuel Shutoff Valve
Optional
Certified Power Rating

*All power levels are stated gross torque at 2600 rpm per SAE J1940 as rated by Briggs & Stratton.

Model Number
121R
Torque (ft-lbs, gross)*
8.5
Engine Displacement (cc)
190
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
15.8
Width (in)
12.8
Height (in)
9.4
Weight (lbs)
24.3
Bore (in)
2.69
Stroke (in)
2.04
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
0.27
Oil Capacity (oz)
18
Lubrication System
Dura-Lube Splash Lubrication
Oil Filter
Optional
Starter
ReadyStart® Starting System
Air Filter
Dual-Sealing Commercial-Grade Air Cleaner
Muffler
Super Lo-Tone™
Fuel Shutoff Valve
Optional
Certified Power Rating

*All power levels are stated gross torque at 2600 rpm per SAE J1940 as rated by Briggs & Stratton.

Torque (ft-lbs, gross)*
9.5
Engine Displacement (cc)
223
Number of Cylinders
Single
Engine Configuration
Vertical Shaft
OHV Engine
Yes
Length (in)
15.8
Width (in)
13.4
Height (in)
10.1
Weight (lbs)
31
Bore (in)
2.91
Stroke (in)
2.04
Engine Fuel
Gasoline
Fuel Tank Capacity (gal)
0.3
Oil Capacity (oz)
18
Lubrication System
Dura-Lube Splash Lubrication
Oil Filter
Optional
Starter
ReadyStart® Starting System
Air Filter
Dual-Sealing Commercial-Grade Air Cleaner
Muffler
Super Lo-Tone™
Fuel Shutoff Valve
Optional

*All power levels are stated gross torque at 2600 rpm per SAE J1940 as rated by Briggs & Stratton.

Torque (ft-lbs, gross)*
10
8.5
9.5
Engine Displacement (cc)
223
190
223
Number of Cylinders
Single
Single
Single
Engine Configuration
Vertical Shaft
Vertical Shaft
Vertical Shaft
OHV Engine
Yes
Yes
Yes
Length (in)
15.8
15.8
15.8
Width (in)
13.4
12.8
13.4
Height (in)
10.1
9.4
10.1
Weight (lbs)
31
24.3
31
Bore (in)
2.91
2.69
2.91
Stroke (in)
2.04
2.04
2.04
Engine Fuel
Gasoline
Gasoline
Gasoline
Fuel Tank Capacity (gal)
0.3
0.27
0.3
Oil Capacity (oz)
18
18
18
Lubrication System
Dura-Lube Splash Lubrication
Dura-Lube Splash Lubrication
Dura-Lube Splash Lubrication
Oil Filter
Optional
Optional
Optional
Starter
ReadyStart®
ReadyStart® Starting System
ReadyStart® Starting System
Air Filter
Dual-Sealing Commercial-Grade Air Cleaner
Dual-Sealing Commercial-Grade Air Cleaner
Dual-Sealing Commercial-Grade Air Cleaner
Muffler
Super Lo-Tone™
Super Lo-Tone™
Super Lo-Tone™
Fuel Shutoff Valve
Optional
Optional
Optional
Model Number
121R

*All power levels are stated gross torque at 2600 rpm per SAE J1940 as rated by Briggs & Stratton.

Support

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