STIHL MS 500i Professional Petrol Chainsaw

STIHL MS 500i professional fuel-injected chainsaw

The STIHL MS 500i is a high-output professional petrol chainsaw designed for trained forestry, woodland and timber-production operators working with large timber.

Its 79.2cm³ STIHL 2-MIX engine produces 5.0kW / 6.8hp and uses electronically controlled fuel injection instead of a conventional carburettor. Pressure and temperature sensors provide information to the electronic control unit, which continuously calculates the required fuel quantity and ignition timing.

This gives the MS 500i fast acceleration, immediate throttle response, simple starting and consistent performance across changing temperatures, air pressures and operating conditions.

The machine is available from Masseys with a choice of 50cm / 20-inch or 63cm / 25-inch guide bar.

• 79.2cm³ STIHL 2-MIX petrol engine
• 5.0kW / 6.8hp power output
• 6.3kg without fuel, guide bar or saw chain
• Power-to-weight ratio of approximately 1.24kg/kW
• Electronically controlled STIHL Injection
• Rapid chain acceleration
• 50cm / 20-inch or 63cm / 25-inch guide-bar options
• Professional 3/8-inch cutting system
• Simplified starting sequence
• Adjustable STIHL Ematic lubrication
• Side-mounted chain tensioning
• Captive sprocket-cover nuts
• Optimised bumper spikes
• Slim sprocket cover for efficient chip clearance
• Plunge-cutting direction guide
• STIHL anti-vibration system
• Tool-free fuel and chain-oil caps

Browse the complete STIHL petrol chainsaw range or view all STIHL chainsaws at Masseys.

Is the STIHL MS 500i right for your work?

The MS 500i is intended for trained and experienced professional operators who need high cutting output, rapid acceleration and strong performance in large timber.

Typical applications include:

• Professional forestry and woodland management
• Felling large hardwood and softwood trees
• Snedding and delimbing felled timber
• Cross-cutting large stems and logs
• Processing commercial timber
• High-volume firewood production
• Farm, estate and contracting work
• Work where rapid recovery of chain speed improves productivity

The MS 500i is not intended as an occasional domestic chainsaw. Customers cutting small quantities of firewood, pruning garden trees or completing occasional property maintenance will normally be better served by a smaller model.

Windblown trees, storm-damaged timber, hung-up trees, heavily leaning stems and technically difficult felling require appropriate training, risk assessment and competence.

Masseys recommendation

Choose the MS 500i when high output and exceptionally rapid acceleration matter more than owning the lightest possible all-round forestry saw.

The STIHL MS 400.1 C-M is generally the more manageable all-round option for medium-to-large professional forestry work.

The MS 500i becomes the better choice where large timber, repeated production cutting and rapid throttle response justify the additional displacement, weight and purchase cost.

For the heaviest felling work and consistently very large timber, compare the larger STIHL MS 661 C-M.

Why STIHL fuel injection matters

Electronically controlled fuel delivery

The MS 500i was the world’s first production chainsaw with electronically controlled fuel injection.

Pressure and temperature sensors monitor operating conditions, while the control unit continuously calculates:

• The required fuel quantity
• The correct injection timing
• The appropriate ignition timing
• Adjustments for temperature and air pressure
• Adjustments for current engine conditions

This removes the need for a conventional carburettor and routine manual carburettor adjustment.

Rapid acceleration

STIHL states that the chain accelerates from 0 to 100km/h in approximately 0.25 seconds.

This rapid response is useful during professional felling, snedding and production cutting, where the operator repeatedly returns the engine to cutting speed between cuts.

The acceleration figure refers to the speed of the moving chain rather than the physical travel speed of the chainsaw.

Simplified starting

The electronic injection system removes the need for a separate conventional choke or start position.

A manual fuel pump and decompression valve support starting. The decompression valve temporarily reduces cylinder compression, lowering the effort required on the starter cord.

Operators must still follow the correct starting procedure in the STIHL instruction manual.

79.2cm³ professional STIHL 2-MIX engine

The 79.2cm³ STIHL 2-MIX engine produces 5.0kW / 6.8hp.

Despite this output, STIHL lists the machine at approximately 6.3kg without fuel, guide bar or saw chain. This creates a power-to-weight ratio of approximately 1.24kg/kW.

The STIHL 2-MIX design is intended to provide strong output while reducing fuel consumption and exhaust emissions compared with older conventional two-stroke engine designs. The engine complies with current EU Stage V requirements.

Choosing a 20-inch or 25-inch guide bar

Both versions use the same 79.2cm³ engine and produce the same 5.0kW / 6.8hp output. The guide-bar choice changes reach, balance and cutting-attachment weight; it does not change engine power.

50cm / 20-inch version

The 20-inch version provides the more manoeuvrable and balanced general-forestry configuration.

Choose the 20-inch version when:

• You regularly fell and process medium-to-large timber
• You value manoeuvrability during snedding and delimbing
• You do not consistently need the additional reach of a 25-inch bar
• You want to minimise cutting-attachment weight
• The saw will be used as a fast all-round high-output forestry machine

The current STIHL manufacturer part number for the 20-inch version is 11472000000.

63cm / 25-inch version

The 25-inch version provides additional reach for larger-diameter stems and heavier felling or cross-cutting work.

Choose the 25-inch version when:

• You regularly process larger-diameter timber
• The additional bar reach is genuinely required
• You have sufficient training and experience to handle the longer attachment
• Your chain, bar, sprocket and sharpening equipment are maintained for professional use
• The additional weight and reduced manoeuvrability are acceptable

 

Professional 3/8-inch cutting system

The MS 500i uses a professional 3/8-inch cutting system.

The exact chain depends on the selected guide bar, groove width and drive-link count. Do not order a replacement chain based only on the model name.

Check the markings stamped on the fitted guide bar or ask Masseys to identify the correct replacement through our chainsaw chain range.

Adjustable STIHL Ematic lubrication

The STIHL Ematic system combines the guide bar, Oilomatic saw chain and controlled-delivery oil pump to direct lubricant to the areas where it is required.

STIHL states that the Ematic system can reduce chain-oil consumption by up to approximately 50% compared with a cutting attachment without the system.

Oil delivery can be increased when working in dusty conditions or when the fitted cutting attachment requires additional lubrication.

Suitable chainsaw chain oil must be added before the machine is used.

Purchase suitable STIHL chainsaw chain oil separately from Masseys.

Optimised bumper spikes and sprocket cover

The bumper spikes are shaped to engage securely with the timber during appropriate cross-cutting and felling work.

The narrow sprocket cover improves chip clearance and includes guide surfaces that help the saw move smoothly along the trunk during professional snedding work.

Captive sprocket-cover nuts remain attached when the cover is removed, reducing the risk of losing them during bar and chain maintenance.

Plunge-cutting direction guide

A moulded guide on the fan housing runs parallel with the guide bar.

It can help a trained operator assess cutting direction when using appropriate plunge-cutting or bore-cutting techniques.

Plunge cutting is an advanced technique with significant kickback risk and should only be attempted by properly trained operators.

STIHL anti-vibration system

Buffer and spring elements reduce the amount of engine and cutting vibration transmitted to the handles.

This can improve comfort during appropriate professional use. It does not eliminate vibration, so exposure time, technique, task rotation and rest periods still need to be managed.

Fuel and chain-oil requirements

The MS 500i requires two separate fluids:

• A 50:1 mixture of suitable petrol and approved two-stroke engine oil, or a compatible premixed alkylate fuel
• Dedicated chainsaw chain oil for the guide bar and moving saw chain

Browse Masseys’ range of garden-machinery fuel and two-stroke oil.

The two-stroke fuel mixture lubricates the engine internally. It does not lubricate the guide bar and chain.

Fuel, engine oil, chain oil and protective equipment are not included unless expressly stated in the selected offer.

What is included?

The selected configuration normally includes:

• STIHL MS 500i professional petrol chainsaw
• Selected 50cm / 20-inch or 63cm / 25-inch guide bar
• Matching professional STIHL saw chain
• Guide-bar scabbard
• Combination servicing tool
• Standard operating and safety documentation

Masseys assembles, checks, starts and tests the chainsaw before collection or qualifying handover and registers the applicable STIHL warranty.

Packaging can change. Contact Masseys before ordering if a particular loose accessory is essential.

STIHL MS 500i technical specifications

STIHL MS 400.1 C-M vs MS 500i vs MS 661 C-M

Choose the MS 400.1 C-M when lower weight and all-round forestry handling are the priorities.

Choose the MS 500i when acceleration, high output and productivity in large timber matter most.

Choose the MS 661 C-M when the workload consistently involves the largest timber and greater engine displacement is required.

Maintenance and Service Kit 17

The MS 500i requires routine professional maintenance to remain safe and provide consistent performance.

• Check chain tension before and during use
• Keep the saw chain correctly sharpened
• Maintain the chain-oil level
• Set oil delivery correctly for the cutting attachment and conditions
• Clean the guide-bar groove and oil holes
• Remove sawdust from the sprocket-cover area
• Inspect the guide bar, chain and drive sprocket for wear
• Inspect and maintain the air filter
• Use clean, correctly mixed fuel
• Follow the service schedule in the STIHL instruction manual

STIHL Service Kit 17 contains an HD2 air filter, spark plug and fuel filter for routine MS 500i maintenance.

Browse STIHL service kits or use Masseys’ garden machinery servicing and repair workshop for professional maintenance, repairs and chain sharpening.

Professional chainsaw safety

The STIHL MS 500i is a high-output professional chainsaw capable of causing serious or fatal injury if used incorrectly.

• Read the complete STIHL operating and safety manuals
• Obtain appropriate practical chainsaw training
• Wear professional chainsaw trousers and protective boots
• Use suitable gloves and head, face, eye and hearing protection
• Operate the chainsaw with both hands
• Check chain-brake operation, chain tension and lubrication before work
• Establish an appropriate exclusion zone
• Assess timber condition, weather, escape routes and surrounding hazards
• Do not use a rear-handle chainsaw from a ladder
• Do not cut above shoulder height
• Only suitably trained professionals should handle windblown, hung-up, split, leaning or storm-damaged timber

Browse our chainsaw trousers and full range of chainsaw accessories and protective equipment.

Frequently asked questions

Is the STIHL MS 500i a professional chainsaw?

Yes. It is a professional forestry chainsaw intended for trained, experienced operators felling, snedding and processing large timber.

What makes the MS 500i different?

Its defining feature is electronically controlled fuel injection. Pressure and temperature sensors provide data to the electronic control unit, which calculates fuel quantity and ignition timing according to operating conditions.

Does the MS 500i have a carburettor?

No conventional carburettor is used. Fuel is metered electronically and injected according to calculations made by the control unit.

How powerful is the STIHL MS 500i?

Its 79.2cm³ engine produces 5.0kW / 6.8hp.

How much does it weigh?

STIHL lists a machine weight of approximately 6.3kg without fuel, guide bar or saw chain. The complete working weight is higher after the selected cutting attachment and fluids are added.

How quickly does it accelerate?

STIHL states that the moving chain accelerates from 0 to 100km/h in approximately 0.25 seconds.

Should I choose the 20-inch or 25-inch version?

Choose the 20-inch version for more balanced, manoeuvrable general forestry work. Choose the 25-inch version when additional reach is regularly required for larger-diameter timber. Both use the same engine and produce the same power.

Is the 25-inch version more powerful?

No. Guide-bar length does not change the 79.2cm³ engine or its 5.0kW output.

Is the MS 500i suitable for firewood?

Yes, particularly for commercial or high-volume firewood production involving large timber. It is unnecessarily powerful and expensive for occasional small domestic firewood.

What fuel does it use?

It uses a 50:1 mixture of suitable petrol and approved two-stroke engine oil, or a compatible premixed alkylate fuel.

Does it require separate chain oil?

Yes. Dedicated chainsaw chain oil must be added to operate the automatic guide-bar and chain-lubrication system.

Can an inexperienced user operate an MS 500i?

The MS 500i is intended for trained and experienced professional operators. Appropriate chainsaw instruction, PPE and competence are essential.

Does Masseys prepare the chainsaw?

Masseys assembles, checks, starts and tests the machine before qualifying collection or handover and registers the applicable STIHL warranty.

Can Masseys service the MS 500i?

Yes. Masseys’ in-house machinery workshop provides servicing, maintenance, repairs, chain sharpening and access to genuine STIHL parts and consumables.

Why buy the STIHL MS 500i from Masseys?

Masseys is an authorised STIHL dealer based in Woodville, near Swadlincote, Derbyshire.

Our team can help you compare the MS 400.1 C-M, MS 500i and MS 661 C-M, choose the appropriate bar length and identify the correct chains, oils, fuel, maintenance equipment and protective clothing.

• Genuine UK STIHL product
• Advice from an established STIHL dealer
• 20-inch and 25-inch configurations
• Machine assembly and pre-delivery checking
• Engine started and tested before qualifying handover
• STIHL warranty-registration assistance
• Genuine STIHL bars, chains, fuels and oils
• Workshop servicing and chain sharpening
• Local collection and qualifying delivery options

Visit Masseys at 129 Swadlincote Road, Woodville, Swadlincote, Derbyshire DE11 8DA, or contact the Masseys team for professional chainsaw and cutting-attachment advice.