Stihl model · engine series 1122
MS 660 91.6 cc
- Chain
- 3/8″ · .063″ · .404″ on long bars
- Recommended bar
- 20–36″
- Mount
- 3003 / D025
MS 660 chain size: 3/8″ · .063″ · .404″ on long bars, 3003-mount bar. Typical STIHL drive-link counts for 3/8" (full) chain: 20″ = 72, 22″ = 76, 25″ = 84, 28″ = 91, 32″ = 105, 36″ = 114. Count the links on your old chain or read the bar stamp before ordering.
Model displacement · family chain/bar fitment. Details & confidence ↓
See also: 064/066 · MS 660 · MS 650/640 family specs · chain and file size guide · part number lookup
Parts diagrams (19)
Browse saved diagrams & other models ↗486 parts entries · catalogue coverage: MS 660. Check the sheet’s variant and serial notes.
Model & family fitment specs
Displacement is specific to the MS 660 roster record. Chain, bar and mount are the published family fitment for engine series 1122; confirm the pitch, gauge and drive-link count stamped on your installed bar before ordering.
Chain, bar and mount: family research from STIHL product pages and parts catalogues, dealer fiche and collector records. Checked Jul 2026. How we check fitment
Chains & bars that fit the MS 660
Pitch & gauge 3/8″ · .063″ · .404″ on long bars · recommended bar 20–36″ · bar mount 3003 / D025 · round file 7/32" (5.5 mm) for Oregon; STIHL lists 13/64" (5.2 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 selection chart and depend on the bar mount as well as length. Pick the chain link that matches the gauge stamped on your bar. Bar searches include mount 3003 / D025; still confirm the mount stamp, pitch, gauge and drive-link count on your installed bar before ordering.
Drive-link counts: STIHL 2025 US catalog, saw chain selection, pp. 166-167; Oregon chain fit guide, STIHL section. Checked Nov 2026. How we check fitment
Files, oil & sharpening
Suggested match: Oregon 72 (.050″) / 73 (.058″) / 75 (.063″) series, e.g. 72/75 EXL. Match the gauge and confirm the drive-link count for your exact bar 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.
Some links earn us a commission. It never changes the specs or what we recommend.
Service & tuning
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 3504 |
| Air filter | 0000 140 4402 HD2 |
| Starter rope | 4.5 mm · 39.5″ |
| Guide coverage | 064 · 066 · MS 650 · MS 660 |
| Source | 2019 STIHL Technical Reference Guide · sourced |
- Guide lists MS 650 at 84.9 cc and 066/MS 660 at 91.6 cc.
Factory tuning settings
| Idle speed | 2,500 rpm |
| LA screw (idle stop) | 1/4 turn |
| Confidence | sourced |
Screw figures are turns open from lightly seated. 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.
About the MS 660
MS-era 066
Production, market and rarity are specific to this model’s roster record.
Related models in series 1122
Shared engine-family membership does not establish parts interchangeability.
Data confidence
Chain, bar, mount and displacement confidence comes from the shared 064/066 · MS 660 · MS 650/640 family research.
Something wrong or missing for the MS 660? Report a correction →