When it comes to professional-grade chainsaws, Stihl stands at the top of the industry. Their models are known for power, precision, and rugged durability. Among the most discussed in their lineup are the Stihl MS 661 and the Stihl MS 500i. These two chainsaws are often pitted against each other by loggers, arborists, and forestry professionals trying to determine which one suits their work best.
Although both are premium chainsaws, they differ significantly in technology, weight, fuel efficiency, and application. This article will dive deep into both models, comparing their specs, strengths, and real-world performance to help you decide which one might be your perfect match.
Overview of the Stihl MS 661
The Stihl MS 661 C-M is a true workhorse. Built for heavy-duty felling and large-scale logging, it’s designed to handle the most demanding tasks. It is equipped with Stihl’s M-Tronic engine management system, which automatically adjusts fuel and air mixture based on altitude, temperature, and fuel quality.
Key Specs:
- Engine Displacement: 91.1 cc
- Power Output: 7.2 bhp
- Weight (without bar and chain): 16.5 lbs (7.5 kg)
- Fuel Capacity: 27.1 oz
- Bar Length Options: 20″–36″
- Chain: 3/8″ RS or RS3
This saw is built for reliability in harsh environments. Its magnesium crankcase, heavy-duty air filtration system, and anti-vibration technology make it a go-to tool for professional loggers who spend long hours cutting large hardwoods.
Overview of the Stihl MS 500i
The Stihl MS 500i is revolutionary. It is the world’s first chainsaw with electronically controlled fuel injection, giving it the edge in instant throttle response and efficient fuel usage. Designed with performance and innovation in mind, this chainsaw is both powerful and nimble.
Key Specs:
- Engine Displacement: 79.2 cc
- Power Output: 6.7 bhp
- Weight (without bar and chain): 13.9 lbs (6.3 kg)
- Fuel Capacity: 26.5 oz
- Bar Length Options: 16″–36″
- Chain: 3/8″ RS or RS3
The MS 500i is lighter than the 661 but still offers incredible power. Its power-to-weight ratio is among the best in its class, making it ideal for professionals who want performance without fatigue.
Performance Comparison
1. Power and Torque:
While the MS 661 is slightly more powerful with 7.2 bhp compared to the MS 500i’s 6.7 bhp, the difference in real-world cutting is subtle. The 661’s raw torque makes it ideal for sustained cutting through thick hardwoods, especially with long bars. However, the MS 500i’s instantaneous acceleration gives it an edge in fast-paced tasks like limbing and quick felling.
2. Weight and Balance:
This is where the MS 500i shines. It is nearly 3 lbs lighter than the 661. That may not seem like much on paper, but in actual fieldwork, it can reduce fatigue significantly. The 500i also has a more centralized balance, making it easier to maneuver, especially when working overhead or in awkward positions.
3. Starting and Throttle Response:
Thanks to the fuel injection system, the MS 500i starts faster and responds to the throttle with lightning speed. Cold starts are smoother, and there’s no need to adjust carburetors manually. The MS 661 also starts reliably with its decompression valve and ElastoStart system, but it’s slightly slower than the 500i.
Technology and Innovation
The Stihl MS 500i represents the cutting edge of chainsaw technology. Its smart electronic control system adjusts fuel injection in real time, optimizing performance under all conditions. It also has fewer parts than a traditional carburetor system, potentially reducing maintenance issues.
The MS 661, while more traditional, still features advanced tech like M-Tronic engine management, which automatically tunes the carburetor. For users who prefer analog simplicity, the 661 might feel more familiar and easier to maintain in remote locations.
Fuel Efficiency
The MS 500i tends to be more fuel-efficient under average workloads due to its optimized injection system. However, when pushed to extreme cutting jobs over extended periods, the MS 661’s larger engine can sometimes provide better fuel longevity. Still, in terms of emissions and cleaner burns, both models are compliant with EPA and EU Stage II standards.
Maintenance and Durability
Both saws are built to last. The MS 661’s rugged construction makes it an excellent choice for dirty, dusty, and extreme conditions. It features a HD2 air filter, which keeps debris out of the engine, extending life.
The MS 500i, while equally durable, has fewer moving parts in its fuel system. That can be a benefit in the long run, but it also means that diagnostics require special tools or knowledge of electronic systems. For remote operations where high-tech support isn’t available, the MS 661 may be the better choice.
Best Use Scenarios
- MS 661: Perfect for professionals doing full-time felling, especially in dense forests with thick trees. It’s also ideal for mill work, rescue operations, and large-scale timber harvest.
- MS 500i: Best for users who want power without weight. Great for arborists, tree surgeons, or firewood processors. It’s also a strong choice for anyone who values advanced tech and fast performance.
Price Comparison
As expected, both saws sit at the premium end of the price spectrum. The MS 500i is typically a bit more expensive due to its innovative injection system. The MS 661, while still pricey, often comes in slightly under the 500i in most markets. However, both are considered long-term investments that pay off in performance and durability.
Conclusion: Which One Is Right for You?
Choosing between the Stihl MS 661 and the Stihl MS 500i depends entirely on your needs and preferences:
- If you need maximum power, rugged durability, and plan to use longer bars for big timber—go with the MS 661.
- If you prioritize lightweight operation, faster starts, and cutting-edge innovation—choose the MS 500i.
There’s no bad choice here. Both chainsaws represent the best of what Stihl offers. For old-school loggers, the 661 may feel more reliable. For modern professionals looking for the future of chainsaws, the 500i is a glimpse of what’s next.
No matter which you choose, you’re getting a powerhouse tool that’s built to cut through the toughest jobs with ease and precision.
