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K&N Engineering

K&N HA-4250 High-Flow Air Filter

Regular price
$70.95
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Sale price
$70.95
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In Stock: 8

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Product Specification:

SKU:KNNHA-4250

MPN: HA-4250

UPC: 024844005656

Weight: 1.0 lb

Inventory: 8

Type: Air Filters - Drop In



Product Fitment

  • 1986-1989 Honda TRX250R FourTrax (all trims, 250 cc 2-Stroke/4-Stroke - see OEM fitment guide)

Features

  • High-flow cotton gauze filter media for improved airflow and engine performance
  • Pleated design increases filtration surface area for long service intervals
  • Washable, reusable and pre-oiled, ready for installation out of the box
  • Direct OEM air-box fit with application-specific sealing bead for a secure fit
  • No fuel-management modifications required for performance gains
  • Improved horsepower and acceleration compared to stock filter in off-road and powersport conditions
  • Durable construction suitable for ATV/off-road use
  • Lightweight design helps maintain throttle response and efficiency

Specifications

  • Filter Shape: Tapered Conical
  • Base Outside Diameter: 4.75 in (121 mm)
  • Top Outside Diameter: 3.5 in (89 mm)
  • Flange Inside Diameter: 4 in (102 mm), Flange Length: 0.625 in (16 mm)
  • Height: 6 in (152 mm)
  • Weight: ~1.1 lb (0.5 kg)
  • Material: Multi-layer woven cotton gauze

Included Components

  • 1x High-Flow Air Filter (HA-4250)

Product Description

The K&N HA-4250 High-Flow Air Filter is a premium, reusable replacement designed to directly replace the stock air filter on compatible recreational and off-road vehicles like the Honda TRX250R FourTrax (1986-1989). Its multi-layer cotton gauze media and pleated conical design enhance airflow while providing effective filtration - ideal for dusty, off-road and ATV riding conditions.

Because it is washable and reusable, the HA-4250 reduces long-term maintenance costs compared to disposable filters, while delivering improved throttle response, acceleration, and engine breathing. Installation is straightforward: the filter drops into the OEM airbox and seals with the dedicated sealing bead, with no modifications or fuel-system tuning required.

Whether you're using your ATV for recreation, trail riding, or work, HA-4250 offers a durable and efficient upgrade over stock filtration - combining performance, reliability and long service life in one high-quality package.

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