164090 Idler Pulley Compatible with King Kutter RFM Series 4', 5' and 6' Finish Mower (2 Pack)

What It Is

This is a replacement idler pulley (2-pack) for King Kutter RFM (Rear Finish Mower) Series decks in 4’, 5’, and 6’ widths. It guides and tensions the mower belt, keeping the blades engaged and running smoothly.

Fitment & Compatibility

Before buying, confirm your mower is a King Kutter RFM Series (not a different brand or a rotary cutter). Measure the pulley’s outside diameter (OD) and bore size: this part is typically 4" OD with a 1/2" or 5/8" bore – verify against your original. Check that your belt is a standard A-section or B-section (common on these decks). The 2-pack covers both idler positions on most RFM models. If your unit uses a different pulley diameter or a sealed bearing type, this may not fit.

Key Things to Know

• Quality: Aftermarket part, not OEM King Kutter. Reviews note it works well for the price, but the bearings may be less durable than OEM in heavy use.
• Installation: Straightforward – remove the old pulley, slide the new one onto the spindle, and secure with the retaining ring or bolt. No special tools needed.
• Gotcha: Some RFM models use a flanged idler pulley; this is a flat pulley. Check your original before buying.
• Gotcha: The 2-pack is a good value, but you may only need one – measure both idlers to be sure.

Should You Buy It

If you own a King Kutter RFM 4’, 5’, or 6’ finish mower and need a budget-friendly replacement for worn idler pulleys, this 2-pack is a solid choice. It’s not built for commercial abuse, but for home or light farm use it’s a practical, cost-effective fix.