Stihl model · engine series 1144
MS 661 C-M Magnum 91.1 cc
⚠ US marketing name; identical to C-M
The production, market and rarity details above are specific to the MS 661 C-M Magnum roster record. The displacement below is specific to this roster record. The chain, bar and mount are the published family fitment for engine series 1144; confirm the pitch, gauge and drive-link count stamped on your installed bar before ordering.
Model & family fitment specs
Chains & bars that fit the MS 661 C-M Magnum
Pitch & gauge 3/8″ · .063″ · .404″ on long bars · recommended bar 20–36″ · bar mount 3003 / D025 · round file 7/32" (5.5 mm)
Chain & bar by length
| Bar | Drive links | Shop |
|---|---|---|
| 20″ | 72 DL | Chain → Bar · 3003 → |
| 22″ | 76 DL | Chain → Bar · 3003 → |
| 25″ | 84 DL | Chain → Bar · 3003 → |
| 28″ | 91 DL | Chain → Bar · 3003 → |
| 32″ | 105 DL | Chain → Bar · 3003 → |
| 36″ | 114 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 72/73/75 EXL. 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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Factory tuning settings
| Max speed | 13,500 rpm |
| Confidence | reconstructed |
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.
Parts diagrams (26)
482 part numbers. The catalogue files these under the MS 661, one bill of material covering this model.
Related models in series 1144
Data confidence
Chain, bar, mount and displacement confidence comes from the shared MS 661 (MAGNUM®) family research.
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