Balance
A step by step analysis of the reciprocating engines' mechanism.
An approximation of the unbalanced inertia loads (force, torque and moment) in  typical (in line and in Vee) and strange (in star, in W etc) cylinder arrangements.
Easy 'Fourier' analysis and resynthesis of the loads mentioned.
Addition and modification of counterbalancing shafts (of any kind and speed) and check of their effectiveness in vibration reduction.
Click here for many examples in separate file.

Actually a calculator specifically made for reciprocating engines, a tool for that one who needs to understand what is going on inside engine.

RoadLoad 
With this program you can see the relation between the used gear ratio, the speed of the vehicle and the force which is applied to the vehicle and passengers from the road. You can compare the ROAD LOADS (as function of the used gear and of the vehicle velocity) of a number of vehicles all in the same graph.
You can compute the best point to change gear, the effect of hard use instead of soft use of the clutch etc, etc.

Keep always in mind: this is an effort to APPROACH reality.

To download the RoadLoad program: click here and save all the files you see in a folder of your computer.

Harmonic
An internal combustion engine having pure sinusoidal motion of its pistons. The balancing of the single cylinder prototype is so perfect that it can stand free on the ground operating from idling to top revs (24 m/sec mean piston speed) without any tend to leave its place.
The slow motion of the piston at TDC improves the combustion. The absence of thrust load on cylinder wall (and so the absence of piston skirt) is a characteristic. The short height compared to conventional of same stroke, is another one.
Photos of the single cylinder prototype (one with a beautiful blue flame coming out of the exhaust port) can be found in the Pulling Piston Engine Analysis.

Gear
An analysis of the operation of the gearbox and of the clutch. The effect of the surroundings, like uphill and wind, the power distribution, etc. Click here for help/analysis