Stihl engine series 1141 · PRO · in production
MS 261 · MS 271 · MS 291
STIHL has announced the MB02-series MS 300 C-M as the MS 261 C-M's replacement in Europe (deliveries from autumn 2026); the 1141 line remains current.
Chains & bars that fit the MS 261 · MS 271 · MS 291
Pitch & gauge .325″ · .050–.063″ (261 also runs 3/8″) · recommended bar 16–20″ · bar mount 3003 / D025 · round file 3/16" (4.8 mm)
Chain & bar by length
| Bar | Drive links | Shop |
|---|---|---|
| 16″ | 67 DL | Chain → Bar · 3003 → |
| 18″ | 74 DL | Chain → Bar · 3003 → |
| 20″ | 81 DL | Chain → Bar · 3003 → |
Drive-link counts come from STIHL's saw-chain catalog. Bar searches include mount 3003 / D025; still confirm the mount stamp, pitch, gauge and drive-link count on your installed bar before ordering.
Files, oil & sharpening
Suggested match: Oregon 95-series (95VPX) / 21–22 LPX. Confirm the drive-link count for your exact bar length before ordering. These are equivalent aftermarket (Oregon) chains, not genuine STIHL chain — STIHL sells its own chain through its dealer network, and we're not affiliated with STIHL. New to fitment? See the bar-mount identification guide and chain & cutter guide.
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Reference service specs
Reference-only service facts. STIHL revised parts by serial number, market, and production revision; verify against the saw label, IPL, or dealer parts lookup before ordering.
| Spark plug | Bosch WSR 6 F · NGK BPMR 7 A |
| Fuel filter | 0000 350 3515 |
| Air filter | 1141 120 1604 (MS 261 / C-M) · 1141 120 1600 (MS 271 / MS 291) |
| Starter rope | 3.5 mm · 38″ |
| Guide coverage | MS 261 · MS 261 C-M · MS 271 · MS 291 |
| Source | 2019 STIHL Technical Reference Guide · sourced |
- HD2 air filter service-kit coverage differs by model and serial range.
Factory tuning settings
| Idle speed | 2,800 rpm |
| Max speed | 13,000 rpm |
| L screw (low speed) | 1/4 turn |
| H screw (high speed) | 3/4 turn |
| LA screw (idle stop) | 1 turn |
| Confidence | reconstructed |
Screw figures are turns open from lightly seated. These are the figures every model in this family shares; an individual model page may be more specific. Matched on the base model number rather than this exact variant, so treat it as a starting point. Set the final mixture by ear and tachometer against the machine in front of you — running a two-stroke lean to hit a published number is how pistons get scored.
Models in this family (5)
657 part numbers across 30 exploded views — the Diagrams column goes straight to them.
| Model | Years | Market | Rarity | Diagrams | Notes |
|---|---|---|---|---|---|
| MS 261 50.2 cc | 2010→ | Global | Current | 16 | Pro; higher output, 50.2 cc |
| MS 261 C-M 50.2 cc | 2013→now | Global | Current | 16 | M-Tronic |
| MS 261 C-MQ 50.2 cc | 2014–19 | EU | Uncommon | 16 | + QuickStop Super |
| MS 271 Farm Boss 50.2 cc | 2010→now | Global | Current | 14 | 50.2 cc consumer |
| MS 291 Farm Boss 55.5 cc | 2010→now | Global | Current | 14 | 55.5 cc |
Service bulletins (4)
Running changes and fixes STIHL published for this engine family.
- TI 24/2011 Heating element; Fuel hoses; Air filter
- TI 20/2011 Carburetors, Limiter Cap; Accelerator Pump; Summary
- TI 25/2010 New chain saws STIHL MS 271, MS 291
- TI 18/2010 New STIHL MS 261, MS 261 C Chain Saws
Data confidence
Verify anything tagged estimated or approx against STIHL spec sheets.
Something here wrong or missing for the MS 261 · MS 271 · MS 291? Report a correction →