Otto Kudrna

My Feedback: (1)

What fuel to run and not to run !!!!!!!!!

Hello gents and ladies. I get the question all the time about what fuel, or ,am I running the right fuel? Well here it is. Just like all other engines, the RCV will run on most any fuels. But also just like all other engines the RCV has fuel specifications on which it runs the best. Let us first cover the "No-Nos" #1) do not run fuels with more than 15% Nitro. the engines do not require it and the compression is already at the optimum for best performance. You will only achieve a bad case of detonation and may ruin the engine. Also on this same line, the engines do not require as much lubrication as most other engines, they only require a good "grade" of lubrication. If you have too much oil in the fuel, you will once again over-compress the engine and have problems with overheating and detonation. Engine specks call for 14-15% oil out of which 4-7% must be Cantor, and 7-11% be synthetic respectively. I find that 14% oil 50/50 blend works the best. If you cannot find fuel with these specifications, you may call me for guidance or, if you must use fuel with 16 or 17% oil, go down to 5% nitro. Your fuel must always be a castor/ synthetic blend. Castor oil is a natural detonation inhibitor and is still the best lubricant known to us which dose not cost $50 a gallon or more. We are testing new fuels which will allow us to go down to about 7-9% lubrication in the future. I am working closely with Coopers Custom Blend Fuels, to provide you with the best performing fuels. I will keep all of you apprised of any new developments in this area, but so far the fuel we have been testing is performing beyond our expectations, and it is with only 9% lubrication. The test engine has 40+ hours on it, with less than expected wear.

Otto Kudrna, RCV Tech Support Americas

Otto Kudrna

My Feedback: (1)

""""CAUTION"""Do NOT RUN YS Fuel blends in the RCV120

Sometimes I wonder about what FUEL people are thinking when they claim that their fuels are the best. such a claim is unsubstantiated and too general, when they do not know what application their fuel will be used for. Let it be known that I have destroyed a couple of RCV engines with certain specific fuels, which I may not name in order not to slander anyone. I would highly recommend to all modelers that the instruction procedure for your particular engine be followed. Also it must be remember that all engine manufacturers want to sell new engines, so many times they do not object when substandard fuel is used, as long as it allows the engine to survive the warranty period. Since RCV"s main line of engines are not for our models but for Motorcycles and such, they want to see what they can stand and cannot stand. RCV Engines has asked me to represent them in the US because of my extensive running and punishment of their engines. In the process I have found quite a few strengths and weaknesses of their engines. when ever a weakness manifested it self, and was brought to their attention they were very quick to react and fix it. But unfortunately there are certain factors that are beyond their control, and one is the type and quality of fuel being used. One nasty fact that has reared its head, is that you do not want to run the standard 20/20 YS blends of fuel (from any manufacturer) do to the excessive compression and detonation it causes in the RCV engine (especially the RCV120-SP). This fuel will cause extreme vibration and detonation. This blend may cause rod failure, lower crank bearing failure or even gear failure. """"DO NOT RUN THIS BLEND""" or any other blend that has more than 15% nitro or 17% oil or has a straight synthetic oil content. PLEASE PLEASE PLEASE take it from someone who has put over 600 hours on RCV engines, and has learned the do's and don't do's Coopers Custom Blend Fuels has a blend specifically for the RCV engines which has proved itself to be the best to date. For those people that can not get this fuel threw their local hobby shop, I do stock it in 12qt. cases to save on shipping charges. When in doubt, leave a post on this thread.

Thank You
Otto Kudrna, RCV Tech Support Americas

Warjet

My Feedback: (327)

Have very limited fuel selection in the area unless I want to mail order. PowerMaster and Performance Plus fuels are in stock, I use the Performance Plus. The company advertizes on the label 80% castor, 20% Klotz. Anyway, I guess I'll try the PowerMaster and doctor it up. Thanks!

Otto Kudrna

My Feedback: (1)

If in fact this is the case, than the RCV engines would miss fire on this fuel. The engines will run well up to 7% total Caster oil. Anything past that they start to miss-fire with the increase of Caster content this condition gets worse with each percentile increase of Caster oil, until the engine will not start. As I mentioned before, Caster oil is a detonation inhibitor and these engines have a limited plug to fuel exposure time. They do not expose the plug to the fuel mixture 100% of the time like all other engines due. The fuel you want to use has a total Caster content of 12% which is too much. In all other situations I would agree with you about the Caster oil. There is not a better lubricant on the market for engine protection. The PowerMaster 4-cycle 10% fuel in fact has the exact formula recommended by the factory. Wild Cat Premium 10% is only 1% from that formula.

OTTO KUDRNA RCV Tech Support

Wildcat Fuels

The Wildcat Fuels recommended for the RCV engine is Wildcat Premium 10% or 15% Nitro 16% oil, out of which the 10% is nearly identical to the formula run in England in this motor.

Otto Kudrna

My Feedback: (1)

Jerry
I have been recommending your Premium 10% as one of the fuels to use. As I have mentioned before, I use Klotz oil in most of my motorcycles, and just love it ( I have 8 bikes and used to do a lot of racing). The statements I make here are a result of my experience gained by extensive testing of RCV engines (about 600 hours now), and my opinion. Even though there have been fuels, which have been used by fliers in RCV engines, which may have actually harmed the engines. your Premium 10% has always performed well and has been recommended to fliers who like Wild Cat fuels. Most of the problem arises when people do not read the instructions and run the YS blend 20/20 all synthetic.

From now on I will no longer make any more fuel BRAND recommendations in writing on these web sights. I will sell fuel for the RCV engines to any one who desires to purchase it from me.

Fuel Formula recommendations; 14-16% OIL Cast/CYNT Blend. 10-15% Nytro (15% absolutely MAXIMUM) when using the greater amount of oil use the lesser amount of nitro.

Any fuel manufacturer who has fuel matching these specifications in their fuel is invited to post their comments.

Otto Kudrna

lokeetl

Otto,

Is there any source of information on fuels, specifically the ingredients, and the pros and cons of said ingredients, and the reason they are there?
When hearing it from a manufacturer one has to assume some bias in the response, so I would be interested in a third party reference.

Thanks,

Chip W.

Otto Kudrna

My Feedback: (1)

Lokeetl
Call me for this information, I will no longer be discussing the fuel subject in righting on these web sights.

Otto Kudrna (630)321-0580

POWERMASTER

Chip,
The POWERMASTER 4-stroke fuel in 10% or 15% Nitro meets all specifications required by the RCV engines. Use it and I think you will be happy.
Wendell

POWERMASTER

Mr Kudrna,
The POWERMASTER 4-cyle fuel in either 10% or 15% Nitro content fits the requirements of the RCV engine specifications. It is a blend of Castor and Synthetic oils with the Castor content in the required range for these engine.
Wendell

POWERMASTER

Warjet,
Why go to the trouble of doctoring the POWERMASTER fuel. It is blended correctly for the RCV specifications of Castor/Synthetic ratios.
Use the POWERMASTER 4-cycle either in 10% Nitro or 15% Nitro and both you and the engine will be happy.
Wendell