Easy — 1–2 hours
Description
Designed for excellent dry running capabilities and a low coefficient of friction, the National 39930 offers reliable performance. Its specifications include a housing bore of 65.070 mm, an inside diameter of 46.020 mm, and an outside diameter of 65.200 mm. The shaft diameter is 1.812 inches, with a thickness of 0.315 inches and a width of 8.000 mm.
Fitment
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Specifications
| Brand | NATIONAL |
| Part Number | N038 39930 |
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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