Enter the amount of fuel and the desired mix ratio(__:1) and this calculator will tell you the amount of oil needed in both ounces and milliliters.

This calculator can help you make homemade octane booster from a number of chemicals. If you enter the gallons of mixed fuel you wish to make, the octane of the gasoline you will be using, choose and additive, and enter the percentage of the additive that you wish to use this calculator will tell you how much gasoline, selected additve (in either oz or gal), cleaning agent (such as mineral spirits), and lubricating agent (such as transmission fluid) is needed as well as an approximate octane rating of the mixture. The octane rating is likely to be off by a small margin, but it should be a close estimate. You need to research mixture levels and adverse effects of these chemicals. Some of these chemicals can be harmful to fuel lines, sensors, and more. Most are not safe at levels of 30% or higher, some much less. Do your research before deciding to make your own octane booster. This calculator is just here to help anyone that is mixing their own fuel.

Enter tire circumference(in), final drive ratio(__:1), and engine RPM and this calculator will give you the maximum speed for that setup. This may be a bit inaccurate for CVT driven scooters. You would actually need to know the RPM that the clutch bell is turning to be completely accurate. This calculator can give you a good idea of max speed differences using different tire sizes, different gear ratios, or setups that rev a little different.

Enter the bore and stroke in millimeters and the number of cylinders and this calculator will tell you the displacement in both cubic centimeters and cubic inches.

Enter the volume of the cylinder and the volume of the combustion chamber and this calculator will tell you the compression ratio (referred to as secondary compression in 2 strokes). For multi-cylinder engines, just use the columes from one cylinder. If you wish to find the effective (corrected) compression ratio of a 2 stroke engine, enter the effective cylinder volume instead of the total cylinder volume. Don't forget to add the volume of the cylinder head gasket to the volume of the combustion chamber. You can find the head gasket's volume by using the displacement calculator above (enter the gasket's thickness in mm into the stroke field). You also need to take deck height and the piston (dished, flat, or domed) into account.

This calculator will tell you the combustion chamber volume necessary to achieve your desired compression ratio (__:1). If you are using a head gasket, remember that it's volume needs to be subtracted from the combustion chamber volume shown here to get a correct result.

Enter the crankcase volume(cc) and cylinder volume(cc) and this calculator will show you the primary compression ratio of a 2 stroke engine.

Enter the bore diameter(mm) and this calculator will tell you approximate ring end gap settings for the piston rings of a two stroke engine.

Enter the bore diameter(mm) and this calculator will tell you the approximate ring end gap settings for the first and second compression rings of a four stroke piston.

Enter 1/4 mile elapsed time (E.T.) in seconds and trap speed along with the vehicle weight with driver (lb) and this calculator will give you an estimate of horsepower and torqe to the wheel(s) as well as power to weight ratio (HP per lb).