Compare Mowers
List prices are the manufacturer’s published figures, re-checked daily; they exclude tax, freight and dealer setup.
A side-by-side reference of each model's stated specifications. MowerFacts doesn’t give opinions: where a published, spec-derived rule can separate machines we mark a Data Pick and show the rule; here, read the values and decide what fits your needs.
Best suited for
What each model is built for, from its duty class and key specs. This is a neutral reference — MowerFacts does not rank one model above another.
- Kubota Z421KWNC-54 — commercial: daily paid use and high acreage; 54-inch deck; gas powered
- Bad Boy Mowers ZT Avenger — commercial: daily paid use and high acreage; 54-inch deck; gas powered
What’s different? The 5 differences that matter most, from the published figures.
- Z421KWNC-54 uses a Kawasaki FS730V engine; ZT Avenger uses a Kohler engine. The engine maker builds the engine; the mower maker chooses the model, rating and fit, so the badge alone does not settle output or longevity.
- Z421KWNC-54 has a Hydro-Gear Commercial ZT-3600 transmission; ZT Avenger has a Dual Hydro Gear 2800 transmission. The transmission grade tracks duty rating and speed. Grade names are each maker's own and are not comparable across brands.
- Z421KWNC-54 has a published top speed of 10 mph; ZT Avenger has a published top speed of 7 mph, a 3 mph difference. Top speed is the maker's maximum in transport. Mowing speed is lower and depends on grass, terrain and the deck.
- Z421KWNC-54 weighs 870 lbs (394.6 kg); ZT Avenger weighs 745 lbs (338 kg), a 125 lbs difference. Operating weight bears on trailer payload, ramps and soft turf. On its own it says nothing about build quality. What Z421KWNC-54's weight means for a trailer ›
- Z421KWNC-54 holds 6.8 gal (25.7 L) of fuel; ZT Avenger holds 7.8 gal (29.5 L) of fuel, a 1 gal difference. Tank size bounds how long a machine runs between stops. Consumption varies with engine, load and speed, so hours per tank are not fixed.
2 more differences, calculated figures and what isn’t comparable
Other verified differences
- Z421KWNC-54 has a 24 hp engine; ZT Avenger has a 26 hp engine, a 2 hp difference.
- Z421KWNC-54 has a 44.3 ci (726 cc) engine; ZT Avenger has a 45.6 ci (747 cc) engine, a 1.3 ci difference.
Calculated by MowerFacts
- Z421KWNC-54 works out to 4.4 acres/hour; ZT Avenger works out to 3.1 acres/hour, a 1.3 acres/hour difference. Calculated by MowerFacts from deck width and the published top speed at 80% efficiency; it is not a manufacturer figure, and real mowing is slower.
Not comparable
- Fuel Type: not published for ZT Avenger.
- Deck Material: not published for Z421KWNC-54.
- Deck Construction: not published for Z421KWNC-54.
- Drive System: not published for ZT Avenger.
- Cut height range: not published for Z421KWNC-54.
Verified means each manufacturer publishes the figure. A bigger number is only a bigger number; nothing here says which machine is better. The full specification table is below.
Which is faster on your property? › Measure your lawn once and MowerFacts times all 2 against it.
| Spec | Z421KWNC-54 Kubota · Zero-Turn |
ZT Avenger Bad Boy Mowers · Zero-Turn |
|---|---|---|
| List price | dealer quote | dealer quote |
| Engine | ||
| Power Source | gas | gas |
| Displacement | 44.3 ci (726 cc) | 45.6 ci (747 cc) |
| Engine Power | 24 hp | 26 hp |
| Engine Make | Kawasaki FS730V | Kohler |
| Fuel Type | Gasoline | — |
| Deck | ||
| Cutting Width | 54 in (1372 mm) | 54 in (1372 mm) |
| Min Cut Height | — | 1.5 in (38 mm) |
| Max Cut Height | — | 4.5 in (114 mm) |
| Deck Material | — | 3/16" or 7-Gauge Thick Solid Steel |
| Deck Construction | — | 7 Gauge / 4.5mm |
| Deck Gauge | — | 7 |
| Drive | ||
| Transmission | Hydro-Gear Commercial ZT-3600 | Dual Hydro Gear 2800 |
| Ground Speed | 10 mph | 7 mph |
| Drive Tire Size | 24 x 9.5 -14, LP | 20x12-10 Turf |
| Drive System | Belt | — |
| Dimensions | ||
| Weight | 870 lbs (394.6 kg) | 745 lbs (338 kg) |
| Fuel Capacity | 6.8 gal (25.7 L) | 7.8 gal (29.5 L) |
| Length | — | 74.5 in (1892 mm) |
| Height | — | 46 in (1168 mm) |
Where these models differ, explained
Z421KWNC-54: Specs verified against the manufacturer spec sheet on Jun 6, 2026 — kubotausa.com.
ZT Avenger: Specs verified against the manufacturer spec sheet on Jun 6, 2026 — badboycountry.com.
Independent reference database. Specs compiled from manufacturer sources and normalized for comparison; verify with the manufacturer or dealer before purchase.