motor RPMs high when idling

DAMIEN1307

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Actually the correct grade of gas for these little engines is regular 87, but with the ethanol removed or ethanol free. Most everybody buys higher octane fuel because it doesn't have ethanol, but lately, unless you buy the highest octane fuel, there's ethanol in it.
I actually have 87 octane ethanol free available to me here in Alamogordo, NM. However the grade of gas is different in most of the world than it is here in the US when we recommend grades of gas.

Just so you know, when the Chinese builders give you a recommended octane rating to use, just like centimeters, (80cc actually being 66cc in the USA), their gas octane levels are of a difference from ours as well...Many people, even most here in the forums, are not aware of a difference in octane rating numbers in most of the world versus the octane number system used here in the USA.

There are two different ways to measure octane ratingResearch Octane Number (RON) and Motor Octane Number (MON). The Motor Octane Number, being measured under more stringent conditions, is almost always lower than the RON. The US uses something called the Anti-Knock Index (AKI), which is just the arithmetic mean of the RON and the MON, whereas almost everyone else uses just the RON.

If China says use 93 octane, (they are using the RON measuring standard), it is actually 85 to 86 octane by USA standards using the AKI method, (R+M/2) as it is marked on the gas pumps here in the US.

There is a 7 to 8 point difference between the numbers used by China and many other places in the world including Europe vs the number value used here in the USA to rate the octane content/capacity of gasoline...I have no idea what method of measurement for octane rating is used in Saudi Arabia though.
 

Kamalazooz3

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I actually have 87 octane ethanol free available to me here in Alamogordo, NM. However the grade of gas is different in most of the world than it is here in the US when we recommend grades of gas.

Just so you know, when the Chinese builders give you a recommended octane rating to use, just like centimeters, (80cc actually being 66cc in the USA), their gas octane levels are of a difference from ours as well...Many people, even most here in the forums, are not aware of a difference in octane rating numbers in most of the world versus the octane number system used here in the USA.

There are two different ways to measure octane ratingResearch Octane Number (RON) and Motor Octane Number (MON). The Motor Octane Number, being measured under more stringent conditions, is almost always lower than the RON. The US uses something called the Anti-Knock Index (AKI), which is just the arithmetic mean of the RON and the MON, whereas almost everyone else uses just the RON.

If China says use 93 octane, (they are using the RON measuring standard), it is actually 85 to 86 octane by USA standards using the AKI method, (R+M/2) as it is marked on the gas pumps here in the US.

There is a 7 to 8 point difference between the numbers used by China and many other places in the world including Europe vs the number value used here in the USA to rate the octane content/capacity of gasoline...I have no idea what method of measurement for octane rating is used in Saudi Arabia though
yea i know that there is a difference in saudi we use the RON rating so i used 95 octane with the RON rating so 95 RON is 91 AKI and by the way i found that the head gasket was blown so i bought a new one and that solved the problem.

Thank you everybody for helping us newbies
 
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