2 smokesr do like higher octane,but i'd be more worry'd on premix then gas.I've been running Klotz R50 with great reslusts. Get yourself a full synthetic 2-stroke/2-cycle oil it will make your engine last a whole lot longer. Leaded fuel at 100 octane will not prevent detonation better than unleaded fuel at the same true 100 octane or higher. Usage: A high-end two-stroke fuel that offers the benefits of added oxygen and a 100-octane Motor Rating. Only buy enough gasoline that you can easily use up within a two-month period or use a specially formulated fuel mixture like STIHL MotoMix® Premixed Fuel. In fact, in previous threads we have! A: I sure can. On EVERY 2-stroke or small engine of that matter you ALWAYS want to use the highest octane of fuel you can get. Use a minimum of 89 octane gasoline and always use fresh fuel. A Bit of Fuel History - It’s important to remember that in 1970, premium pump gas was often 100+ octane, and this 100-octane was the fuel that virtually all vintage two-strokes were designed to run on. In a 2-stroke engine, these steps still occur but are streamlined into two strokes (the piston goes up once and down once). Re: What octane gas is best to use for a two stroke outboard motor. The easy answer is any and all of the above work for your 4-stroke or blend with premix for a 2-stroke. The octane level is simply the fuel’s detonation resistance. Whether you go the cheap route and grab some 87 octane or think a few bucks more for the 92 premium Techron infused ammunition glides you along faster it all pretty much does the same thing. This Hi-Performance Air Cooled 2-Stroke engine requires the use of MINIMUM 89 Octane (Mid grade or Premium) clean gasoline. Step 2: OIL. Be aware that ethanol is the worst enemy for two-stroke engines. The main difference between premium gas and regular gasoline is that premium gas has a higher octane level. Warning: Gasoline with octane rating lower than 89 will greatly increase engines operating temperature. The manual calls for a unleaded or leaded fuel with a minimum of 87 pump octane. Their premixed oil has a ratio of 50:1 and is suitable for most of their … I would recommend using fresh gasoline that has an octane rating of 89. As we already mentioned, the company sells their range of premixed fuel combos as well as synthetic oils. If you do the math its getting pricey to run a 2stroke.I'll mix 5 gallons,at $4 a gallon,with 1 bottle of mix,$10.Even the 200 only gets 27-28 mpg if im lucky.Its like running Cam2 in the fourstrokes. STIHL MotoMix® is a high-grade, high-octane, ethanol-free premixed fuel containing STIHL HP Ultra synthetic oil. DO NOT use BIA or TCW 2 stroke water cooled engine oils Oils must be classification TC. It also state to mix Stihl 2 stroke engine oil at 50:1 and other brand mix at 25:1. Add Tip Ask Question Comment Download. about the merits or lack thereof of various octane and brands of gasoline and additives. On a two stroke the fuel type and squish speed also effect detonation. You want to mix 2.6 ounces of oil to one gallon of gasoline for a 50:1 mixture. Leaded fuel is better at preventing detonation. If you're mixing up two gallons of gasoline you will have to mix 5.2 ounces of oil to two gallons of gasoline for a 50:1 mixture. It starts your engine and gets you around the track. If we look at the compression stage specifically, then we can see how octane … If your snowmobile is designed to run with 87 octane gasoline you are better off with regular gasoline. The fact is … If octane rating of the Mid Grade gasoline is lower than 89 octane USE Premium Unleaded Gasoline. You Know: We could go on and on ad infinitum (can you spell redundant?) Compared to conventional. It helps your engines performance and longevity. It contains enough octane for highly modified two … The combustion chamber designs employed in most street two-strokes of the 70’s worked great on 100-octane premium. The recommended gas is mid-grade 89 octane, combined with the Stihl branded 2-stroke oils.