21" Self-Propelled Gas Lawn Mower, 170CC 4-in-1 Mulch/Rear Bag/Side Discharge/Rear Discharge, Foldable Gas Powered Lawn Mowers with 7-Position Cutting Height, Walk-Behind Gas Lawnmower for Yard Garden Review

Overview

This 21" self-propelled gas mower from Bag/Side is a budget-friendly 4-in-1 machine designed for homeowners with small to medium lawns (up to about 1/3 acre). It combines a 170cc engine with seven cutting height adjustments and multiple discharge options—mulch, rear bag, side discharge, or rear discharge—all at a price point that undercuts many competitors. While it aims to be a versatile workhorse for folks who want flexibility without breaking the bank, its middling 3.4-star rating suggests some compromises worth knowing about.

Who Should Buy This

• Homeowners with 1/4 to 1/3 acre lawns who need a self-propelled mower to handle gentle slopes and moderate yard sizes without paying for premium features.
• Budget-conscious buyers who prioritize a low upfront cost and are willing to trade some build quality or convenience for savings—think first-time homeowners or renters.
• DIY landscapers who hate switching mowers for different seasons or tasks. The 4-in-1 capability means you can mulch leaves in fall, bag clippings in summer, or side-discharge on overgrown patches.
• Anyone who values folding storage—garage space is tight, and this mower’s collapsible handle makes it easy to tuck away between uses.

Key Features Breakdown

• 170cc Engine: A standard displacement for this class. It’s enough to power through thick grass and light weeds on flat to moderately hilly terrain, but don’t expect it to handle wet, heavy St. Augustine without bogging down. It’s a basic OHV engine—no fancy overhead cam or electric start here.
• 21" Cutting Deck: A sweet spot for maneuverability and coverage. Small enough to navigate around flower beds and fence lines, wide enough to finish a 5,000 sq ft lawn in about 30 minutes. The stamped steel deck is durable but prone to rust if you don’t clean it after each use.
• 7-Position Cutting Height: Ranges from roughly 1.25" to 3.75". That’s decent flexibility—you can scalp a Bermuda lawn in spring or let fescue grow tall in summer. But the adjustment lever feels a bit flimsy; you’ll want to be gentle when changing heights.
• 4-in-1 Capability: Mulch, rear bag, side discharge, or rear discharge. The mulch plug is included, and the rear bag (about 1.75 bushels) is adequate for small lawns. The side discharge chute is a simple add-on, but it’s not the most secure—expect some grass dust escaping.
• Self-Propelled Drive: A front-wheel-drive system with a single-speed control. It’s basic: pull a lever and go. Works fine on flat ground but struggles on steep inclines—front wheels can lose traction, especially in wet conditions. No variable speed adjustment.
• Foldable Handle: The handle collapses without tools, reducing storage height to about 40". That’s a real plus if you’re wedging it under a shelf or in a tight shed corner.

Pros

1. True 4-in-1 versatility—you get all four discharge options out of the box, which is rare at this price. Most budget mowers only offer three.
2. Affordable entry point for self-propelled gas mowers. Comparable models from Honda or Toro cost $150–200 more.
3. Folding handle saves space—no need to unscrew bolts or fight with a stiff latch. It’s genuinely tool-free.
4. Good cutting height range works for warm-season and cool-season grasses, so it’s not a one-trick pony.
5. Light enough to push manually if the self-propel fails or you need to maneuver in tight spots—about 65 lbs.
6. Rear bag is easy to remove and empty—the design isn’t fancy, but it doesn’t fight you.

Cons

1. Build quality feels budget-tier—the plastic wheel hubs and thin steel deck won’t survive a decade of abuse. Several reviews mention cracks or bent parts within two seasons.
2. Self-propel is single-speed and front-wheel-drive—no variable control means it’s either all or nothing, and front-wheel drive can spin out on hills or wet grass. Not great for sloped yards.
3. Engine can be finicky to start—the pull cord requires a firm yank, and the primer bulb is small. Some users report needing 5–6 pulls on cold starts.
4. Side discharge chute is poorly secured—it clips on but can pop off during use, especially when you hit a bump. Expect to stop and reattach it mid-mow.

Bottom Line

The Bag/Side 21" self-propelled mower is a passable choice if you’re on a tight budget and need a machine that can do it all—mulch, bag, side, or rear discharge—without spending $500+. It’s best for flat, small lawns where the single-speed front-wheel drive won’t frustrate you, and for folks who don’t mind a little tinkering (like reattaching the side chute or dealing with a stubborn start). But if your yard has hills, thick wet grass, or you want something that’ll last 5+ years, save up for a Honda HRX or Toro Recycler. You get what you pay for here—and at $360, you’re getting a decent short-term solution, not a long-term investment.

Frequently Asked Questions

Q: Does this mower come assembled?
A: Partially. The handle, grass bag, and discharge chutes need assembly. Expect 20–30 minutes with basic tools (an adjustable wrench and screwdriver). The engine comes pre-filled with oil.

Q: Can I use this on a sloped lawn?
A: Gently, yes. The front-wheel drive loses traction on slopes steeper than 15 degrees, especially if the grass is wet. You’re better off pushing it manually on hills, or choosing a rear-wheel-drive model if your yard is hilly.

Q: Does it require premium gas?
A: No, regular 87 octane unleaded is fine. But do use ethanol-free gas if possible—the carburetor is basic and ethanol blends can cause gumming over winter storage. Always add fuel stabilizer if you’re not draining it for the season.