When it comes to professional-grade chainsaws, Stihl stands at the top of the game. Among their most powerful models, the Stihl MS 661 C and the Stihl MS 500i are two popular choices for loggers, arborists, and landowners needing serious cutting performance. While both saws are built for demanding tasks like felling large trees or processing thick logs, they come with distinct features, technologies, and advantages. In this article, we’ll compare the MS 661 C and the MS 500i to help you decide which one is right for your needs.
Engine Power and Performance
Stihl MS 661 C:
This beast is equipped with a 91.1cc two-stroke engine that delivers around 7.2 horsepower. It’s designed for long, continuous work in extreme conditions. It’s ideal for felling hardwoods, milling large timber, and working in forestry environments. The MS 661 C offers consistent power and torque output, making it reliable under tough workloads.
Stihl MS 500i:
On the other hand, the MS 500i has a slightly smaller engine at 79.2cc, delivering about 6.7 horsepower. What sets it apart is its fuel-injection technology—a first in chainsaws. The MS 500i doesn’t rely on a carburetor like traditional chainsaws. Instead, it uses electronic fuel injection for smoother performance, quicker throttle response, and easier starts in all temperatures.
Verdict:
If you need raw, continuous power and torque for large jobs, the MS 661 C might be the better pick. But if you want quick responsiveness and modern efficiency, the MS 500i’s tech-forward engine has the edge.
Starting System
MS 661 C:
This model includes ElastoStart and a decompression valve to reduce the effort required to pull the cord. The startup is relatively smooth for such a large saw, but it’s still a traditional pull-start system that can be a bit challenging in cold weather or after long idle times.
MS 500i:
This is where the 500i really shines. Thanks to fuel injection, it has an almost effortless starting process. There’s no choke, no priming, and fewer pulls required. Even in cold conditions, it fires up reliably with minimal effort.
Verdict:
The MS 500i is the clear winner for ease of starting, especially if you’re using the saw frequently throughout the day.
Weight and Handling
MS 661 C:
Weighing in at about 16.5 lbs (7.5 kg) without fuel or bar, the 661 is a hefty machine. It’s designed for strength and durability, but not necessarily for light handling. That said, it’s well-balanced, and experienced users won’t have trouble controlling it during long sessions.
MS 500i:
One of the standout features of the MS 500i is its excellent power-to-weight ratio. It weighs only 13.9 lbs (6.3 kg)—making it significantly lighter than the MS 661 C while still delivering serious power. It’s more agile, easier to maneuver in the field, and better suited for working at height or in tight spaces.
Verdict:
The MS 500i offers better handling and less fatigue for the operator, which can increase productivity over time.
Fuel Efficiency and Maintenance
MS 661 C:
The MS 661 C is a traditional gas-powered chainsaw that uses Stihl’s 2-MIX engine to improve fuel efficiency and reduce emissions. While it performs reliably, it does require manual carburetor tuning and regular maintenance of filters and spark plugs.
MS 500i:
The fuel-injection system not only improves performance but also optimizes fuel consumption in real-time. It adjusts automatically to elevation, temperature, and fuel quality, so there’s no need for manual tuning. Plus, maintenance is simplified since there are fewer mechanical parts like carburetors to worry about.
Verdict:
The MS 500i is more fuel-efficient and lower maintenance, making it ideal for users who value convenience and modern design.
Cutting Power and Applications
MS 661 C:
This saw is built for the most demanding jobs. If you’re regularly cutting huge trees, milling timber, or working in commercial forestry, the 661 is built to handle high workloads all day long. It can run long bars (up to 36″ or even 41″ with the right configuration), which is a big plus for massive cuts.
MS 500i:
While slightly less powerful, the 500i still delivers enough force for felling large trees and bucking logs. It works well with bars up to 28″–30″, and because of its lighter weight, it’s often favored for tasks requiring movement or precision.
Verdict:
The MS 661 C is better for extreme-duty and oversized trees. The MS 500i is ideal for professional users who want a balance of power, speed, and control.
Price Comparison
MS 661 C:
Generally, the MS 661 C is slightly more expensive, largely due to its larger engine and industrial-grade build. It’s a saw built for professional foresters who need long-term durability.
MS 500i:
While not cheap by any means, the MS 500i is priced a bit lower. However, the modern technology it brings justifies the investment. It’s a smart choice for professionals who value innovation and comfort.
Verdict:
If price is a concern, the difference may not be significant, but the 500i provides excellent value for its innovative features.
Final Thoughts: Which One Should You Choose?
Both the Stihl MS 661 C and the Stihl MS 500i are top-tier chainsaws built for serious work. Your choice depends on your specific needs:
- Choose the MS 661 C if you need maximum power, plan to use extra-long guide bars, or are frequently involved in large-scale felling and milling. It’s a true workhorse.
- Go with the MS 500i if you value faster starts, easier handling, advanced technology, and a saw that performs efficiently in changing conditions. It’s ideal for pros who want cutting-edge performance without sacrificing power.
In many ways, the MS 500i represents the future of chainsaws, while the MS 661 C holds on to the proven reliability of traditional high-power tools. Either way, you’re getting one of the best saws that Stihl has ever made.
