I have a stihl km 55 r strimmer but i need to know the 2 stroke mix ratio

TO MIX THE FUELSee Figure 3.? The product is powered by a 2-stroke engine and requires pre-mixing petrol with2-stroke oil. Pre-mix unleaded petrol and 2-stroke engine oil in a clean containerapproved for petrol.? The engine is certified to operate on unleaded petrol intended for automotive usewith an octane rating of 91 ([R+M]/2) or higher.? Do not use any type of pre-mixed petrol/oil from fuel service stations, such asthe pre-mixed petrol/oil intended for use in mopeds, motorcycles, etc. Do not useautomotive oil or 2-stroke outboard oil.? Use only synthetic 2-stroke oil.? Mix 2% of synthetic 2-stroke oil into the petrol. This is a 50:1 ratio

if you are asking the oil /fuel ratio for a 2 stroke small engine. not being told the size, make or model makes an answer impossible
however Stihl have a special 2 stroke oil that is mixed at the ratio of 50:1 and that will cover all ratios from 20:1 to 50:1
Saves having different cans for all of the engines that can be a workshop
Mixed correctly it works well and if you want just the one fuel can that includes 4 stroke engines
the 50:1 ratio makes for good upper cylinder lubricant in those engines as well and you will not even see it smoke

it is a petrol engine and the carby listed indicates that it is a 2 stroke
the oil /fuel mix ratio is 50:1 with a fuel octane rating of 91 ( do not use e-mix fuels ) recommended oil from the manufacturer specifications is a synthetic 2 stroke oil
Brand of manufactured oil optional

50:1
consider using stihl 50:1 oil as it is made to run in any 2 stroke engine at any ratio that way you only need one fuel tank correctly mixed for all 2 stroke operations

http://www.csgnetwork.com/oilfuelcalc.html
In the Mix
All STIHL gasoline-powered equipment uses a 50:1 gasoline/oil mixture. The chart below can help you figure out the correct measurements to use. For high-performance fuel that requires no mixing, choose STIHL MotoMix® premixed fuel.

If it is 2 stroke, take petrol /fuel and mix it with preferably synthetic2 stroke oil.

Ratio is usually 10L petrol mixed with 200 ml or 2 stroke oil, that is the best result, used it on my chainsaw, strimmer, moped, working for years without a glitch.

I run a 40:1 ratio in all my 2-stroke equipment. I use my equipment VERY HEAVY every day, and it consists of Stihl, poulon, John Deere, etc... Just don't go over 50:1, or under 32:1 and you should be fine!

hi there keithprobert

the ratio to use if using top quality 2 stroke oil is 50:1 that is 20 mills of 2 stroke oil per 1.0 litre of petrol that you mix.

but if not using top quality 2 stroke oil use ratio 25:1 that is 40 mills of 2stroke oil per 1.0 litre of petrol that you mix.

cheers pauly46

dont forget the thumbs rating

Most trimmers require a mix of regular unleaded fuel and two cycle oil...the ratio is usually 50:1...you can purchase the oil in convienient packages that allow you to add the whole package to 1 gallon of fuel to obtain the proper mix

50:1 is the mixture for the Jonsered 535. I bought mine new around 1991 and it's been a great saw.