§ Fitment Guide
Ryobi PCN3840 chain size & replacement chart
The Ryobi PCN3840 takes a .325" pitch, .050" gauge chain. Below: every factory bar length with its exact drive-link count, cross-referenced to Oregon part numbers, plus the OEM parts list.
Fitment matrix
| Bar length | Pitch | Gauge | Drive links | Oregon chains | Bars / combos |
|---|---|---|---|---|---|
| 16" | .325" | .050" | 66 | 20BPX066G20LGX066G20LPX066X220LPX066GH66Q66 | 160PXBK041 |
| 18" | .325" | .050" | 72 | 20BPX072G20LGX072G20LPX072X220LPX072GH72Q72 | 180GDBK041180PXBK041180RNBK041180VXLGK04155750436892 |
Source: Oregon part-finder, retrieved 2026-07-06. Part numbers link to the manufacturer's spec page. Always confirm drive-link count against your current chain before ordering.
Compatible chains in our shop
How to confirm the fit
- Read your bar. The pitch and gauge are stamped on the guide bar near the saw body — e.g.
3/8" LP .050". - Count drive links. Lay the old chain flat and count the teeth that ride inside the bar groove. This number must match exactly; length in inches is not enough.
- Match all three. Pitch, gauge and drive-link count all have to agree with a row in the table above. Two of three is not a fit.
Watch: how to identify chain pitch and gauge
Oregon Products: Identifying Chain Pitch and Chain Gauge Official video from Oregon Products, the manufacturer behind the cross-reference part numbers above.
Official Ryobi resources
- RYOBI manuals & support — owner's manual for the PCN3840, including tensioning and maintenance intervals.
- RYOBI replacement parts — exploded parts diagrams and OEM part numbers.
FAQ
What size chain does a Ryobi PCN3840 take?
The Ryobi PCN3840 runs a .325" pitch, .050" gauge chain. Available bar lengths: 16", 18". Match the drive-link count to your bar (see the table above).
How do I know which gauge my PCN3840 chain is?
Check the number stamped on your guide bar near the tail, or measure the drive-link thickness with calipers. Common gauges for the PCN3840 are .050".
Can I put a longer bar on my Ryobi PCN3840?
Oregon lists 16", 18" bars for the PCN3840. Stay within this range — a longer bar than the engine is rated for cuts slowly and accelerates wear.