Air and Fuel› Air Cleaners, Filters, Intakes and Components

UNIFILTER

Uni Filter Uni Foam Filter - Hon Dirt

$25.30

SKU: U01K NU-4135ST

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Special Order
Ships in 4–6 weeks
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Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Beginner — under 30 min

Description

The UNIFILTER NU-4135ST is a foam air filter designed for the Honda CR125R and CR250R models from 2002 to 2007. It features a unique two-stage foam design that can be serviced separately, allowing for easy and complete cleaning. This high-flow filter aims to improve performance and provide excellent filtration and engine protection.

It is also noted as the best-selling replacement air filter for competition motorcycles and ATVs. The NU-4135ST does not require rejetting and is made in the USA. It replaces Honda part numbers 17213-KZ4-J40 and 17213-KSR-710.

Fitment

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Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

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Specifications

BrandUNIFILTER
Part NumberU01K NU-4135ST

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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