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MS 661 C-M

MS 661 C-M
A professional chainsaw with enhanced fuel efficiency and STIHL M-Tronic™ technology.

Product Description

When professionals need to fell large trees, in large quantities, they reach for the saw they know has the power to get the job done – the MS 661 C-M. Featuring an impressive power-to-weight ratio and STIHL M-Tronic™ engine management technology, the MS 661 C-M chainsaw also delivers less vibration and 20% greater fuel efficiency than the MS 660. Other features include a long-life filter system using HD-2 filter elements to provide longer run times between maintenance, an ElastoStart™ handle, and a high output adjustable oiler. Wrap-handle version available in select areas. See MS 661 R C-M.

Model Features

  • Reduced-Emission Engine Technology - Caring for Nature
    The STIHL Inc. “Caring for Nature” seal identifies its powered products that are more environmentally conscious, producing zero or low exhaust emissions. STIHL Inc. defines “low exhaust emissions” as being cleaner than EPA and/or CARB exhaust emission standards.

    More information

  • STIHL M-Tronic™ 
    This product features M-Tronic™ (M) - a new generation of Intelligent Engine Management that eliminates the low and high speed carburetor adjustment screws, compensates for dirty air filter and changes in elevation and fuel quality for optimum engine power at all times.

    See it in action!

    More information

  • Anti-Vibration System
    STIHL has developed a system for minimizing the vibration levels of handheld outdoor power equipment. The STIHL anti-vibration system helps reduce operator fatigue and provides a more comfortable working experience.
  • STIHL ElastoStart™
    The ElastoStart™ starter handle is an exclusive feature of STIHL. It is a starting grip with a built-in shock absorber that helps reduce the effort when pulling on the starter cord. The ElastoStart™ starter grip noticeably reduces the sudden peak forces (compression) normally felt during cranking. The forces which occur at the grip after the first compression stroke are smoothed out.
  • Decompression Valve
    The decompression valve, also referred to as 'deco' or 'deco valve', vents compression in the cylinder for easier starting. The decompression valve temporarily reduces the compression in the combustion chamber during cranking and helps reduce the effort needed to pull the starter rope. It is opened manually and closes automatically as soon as the engine fires.
  • Side-Access Chain Tensioner
    The side-access chain tensioner makes it much more convenient for the user to adjust the saw chain with a bar wrench as opposed to the typical location of the guide bar adjustment screw.
  • Adjustable Automatic Oiler
    The Adjustable Automatic Oiler allows the user to adjust the lubricant of the guide bar and saw chain for different bar lengths and cutting conditions.
  • Toolless fuel and oil caps with retainers
    Simply lift the lever and twist the caps to remove or tighten. There‘s no need to use a tool to tighten or loosen.

Specifications

DISPLACEMENT
91.1 cc (5.56 cu. in.)
ENGINE POWER
5.4 kW (7.2 bhp)
POWERHEAD WEIGHT
Flush-Cut: 7.4kg (16.3 lbs.)
Wrap-Handle: 7.66 kg (16.8 lbs.)
FUEL CAPACITY
825 cc (27.9 oz.)
CHAIN OIL CAPACITY
360 cc (12.2 oz.)
OILOMATIC® CHAIN
33 RS3
GUIDE BAR LENGTHS* (Recommended ranges)
40 to 80 cm (16" to 32")
STIHL ROLLOMATIC® E Super
POWER SOURCE
Gas
STIHL recommends #3624 (33 RS3 84) OILOMATIC® saw chain and 25" 3003 000 4030 Ematic™ guide bar combination. The actual listed guide bar length can vary from the effective cutting length depending upon which powerhead it is installed.

Important Information

WARNING! The occurrence called “kickback” can cause serious or fatal injury. Always read the instruction manual carefully before using your saw. STIHL uses a green and yellow color-coding system to help you select a powerhead, bar and chain combination that complies with the kickback requirements of ANSI Standard B175.1 (gasoline-powered saws) and §30 of UL 1662/ ANSI Standard B175.1 (electric chainsaws). Ask your STIHL dealer about safe operating procedures and the advantages of the STIHL Quickstop® chain brake, STIHL Quickstop® Plus (Q) additional chain braking feature, STIHL reduced kickback bars and STIHL low-kickback saw chains.

STIHL recommends the use of green reduced kickback bars and green low kickback chains on all STIHL chainsaws.

* The actual listed guide bar length can vary from the effective cutting length based on which powerhead it is installed on.

Note: STIHL recommends use of fuel with no more than 10% Ethanol content. Using fuel with greater than 10% Ethanol content may cause damage to your equipment and may void your STIHL warranty. Learn More…

WARNING! Improper use of any power tool may cause serious or fatal injury. Read, understand and follow carefully the operating and safety instructions in your instruction manual before using such products.

STIHL products sold through U.S. STIHL Dealers are for distribution in the United States only.

Reviews

MS 661 C-M is rated 4.5 out of 5 by 47.
Rated 5 out of 5 by from This chainsaw has a perfect power to weight ratio. I bought my first stihl saw about 20 years ago.It was the 066 magnum,and it sure did a great job for me. It was used to fell trees and for everyday firewood cutting. I sold this saw due to lack of work. i recently purchased the new MS 661 magnum and WOW is this the saw for me. Plenty of power and very easy to start and surprisingly light weight for its class. This saw will do it all. LOVE MY STIHL. Todd G Robertson.
Date published: 2017-10-11
Rated 5 out of 5 by from Very powerful saw and glad I bought it I needed a 36" bar saw and found the 661 and one other brand's saw. I have a smaller stihl saw so I went with the 661 due to brand awareness. To be honest if it wasn't for this for this specific difficult cut I probably wouldn't have spent so much on a saw but I'm glad I did. The only issue I have had is trying to restart a hot saw but a cleaning of the plug seemed to do the trick. The saw has a huge amount of power and so far I am very happy with it.
Date published: 2017-09-25
Rated 4 out of 5 by from Great Saw This is a great saw for large jobs. It can be a bit heavy after about an hour of use but it can get the job done.I was hoping that it would have just a bit more power than it does, but it still does what I need. Can be a bit tough to start at times.
Date published: 2017-09-20
Rated 3 out of 5 by from chain blade nuts spin off while in use no matter how tightly torqued First of all , I run a tree service and got this saw to cut tree stumps. Plenty of power but blade nuts spin off after about one minute of use. No matter how tight, there's been times I thought I was going to break the stud off. I had to buy nylon self locking nuts to use it. Good luck!
Date published: 2017-09-08
Rated 5 out of 5 by from Nice hefty saw Shy of an 880 for milling or clearing the rainforests - I can't imagine anyone needing a bigger saw. The 661 is a beast. It don't find huge power advantage over the 461, but it's noticeable. Love the MTRONIC. This saw doesn't let down.
Date published: 2017-08-21
Rated 5 out of 5 by from Powerful saw I see a lot of people having a problem with the saw starting after running hot or after running for long periods of time. I found when you re-start any of the saws just pull the cord with out choking or doing anything you would do when cold starting and especially with the mtronics. Usually starts every time one pull because the gas is already there.if you re-choke after running hot, it floods the carburetor causing the no starts.Just pull the cord. Unleash the beast.
Date published: 2017-08-04
Rated 5 out of 5 by from I'm a 3rd generation timberman. Being a Missouri family with German heritage, we have always known what the best saw out there is... Stihl! This saw has made so many advancements, I am very impressed. Have solely operated it for one year now without a hitch, has never shut off when laid down during idle. If you can handle the few extra pounds, the gas tank is larger for fewer fill ups throughout the day, new anti-vibration mounts and springs have really improved kickback vatigue, as well as new air filters. Also, the chain cap cover has nuts that stay in once loosened. Overall, I have not found anything I don't like about the brilliantly engineered advancements that have been developed. Dependability at its finest but hold on, this chainsaw aien't for boys! Way to go Stihl, cheers to taking such pride in the development of this awesome chainsaw.
Date published: 2017-07-28
Rated 5 out of 5 by from Tree eating beast I have a small hard wood timber farm of a few hundred acres and needed to fell and buck some very large red oak, ash and maple. So far I'm into about 70 hours on the saw and it starts on the second pull almost every time. Today when it was 88 degrees out and I stopped for a 20 minute break it didn't act like it wanted to start. I turned ignition to off cranked it three times and then did a normal start and it took right off. Saw has a great power to weight ratio and it's easy to clean and maintain after use. I Stihl (pun intended) use an 044 for light use and a new 193T for in tree work. The 044 has got to be 16 or so years old and still cuts like there's no tomorrow. I clean and tune my own equipment and keep them lubed and clean, they seem to last which brings down the investment when you consider the equipment should last you for many years if properly maintained.
Date published: 2017-07-08
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Standard Features

  • Common Features for Chainsaws
    View the features common to many STIHL chainsaws.

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