Honda 90043-Z8B-000 Bolt, Stud; 90043Z8B000 Made by Honda

What It Is

The Honda 90043-Z8B-000 Bolt, Stud is a genuine OEM fastener used to secure the blade to the crankshaft on select Honda lawn mowers. It’s a stud bolt that threads into the blade adapter, not a standard nut, and is critical for safe blade attachment.

Fitment & Compatibility

• Check your mower’s model number – this stud fits specific Honda HRX, HRS, and HRR series mowers (e.g., HRX217, HRS216, HRR216) with GCV engines. Verify your mower’s model on the Honda parts diagram or serial plate.
• Not universal – it does not fit Honda’s GXV engines or older mowers with a different blade bolt design. Measure the stud’s thread pitch (likely M8x1.25) and length (~27mm) to confirm.
• OEM vs aftermarket – this is a genuine Honda part. Aftermarket studs may have slightly different thread length or hardness, which can affect blade balance or safety.
• Deck size irrelevant – the stud is based on engine crankshaft type, not deck width.

Key Things to Know

• Quality – Honda OEM steel, heat-treated for strength. Aftermarket studs may strip or break under high torque.
• Installation difficulty – Easy, but you must torque the blade bolt to 35-40 ft-lbs (per Honda spec). Use a torque wrench; overtightening can strip threads, undertightening can loosen the blade.
• Common gotcha – The stud has a shoulder that must seat fully into the blade adapter. If the adapter is worn or damaged, the stud won’t hold the blade level. Inspect the adapter before replacing just the stud.
• Price vs value – At ~$6, it’s cheap insurance. A broken stud can send the blade flying.

Should You Buy It

Buy this if you have a compatible Honda mower and need a direct OEM replacement for a stripped, broken, or missing blade stud. It’s the correct, safe choice—skip generic bolts. If your mower is not on the fitment list, measure your existing stud first.