Technical information

We would like to bring to your attention the TUV (Germany) study of consumer properties of Solomon Alsberg’s stock-produced forged wheels. In this study our German colleagues compare the forged wheels designed and manufactured by Solomon Alsberg (Isida and Brig designs) to the standard cast wheels. A formal objective of the study may be defined as follows: wheel weight effect on fuel consumption, acceleration and braking of the car, its performance and control comfort. To this day such information was almost unavailable to the customer and it was privileged and highly technical. At the same time, a lack of information resulted in many disputes and wild guesses by car enthusiasts about what are the differences (other than the price) between forged and cast wheels. The press gives many figures that characterize the difference. However, none of the sources give exact science-based data. This material specifies science-based figures reflecting real difference between forged wheels and cast wheels.
For the purpose of comparison they have used Solomon Alsberg’s Isida and Brig 8.0x18” forged wheels and original cast wheels.

Left to right: original cast wheel, Isida, Brig

The wheels were tested on Audi A6 S-line (C6) with the specific software (“CarSim” specialized simulator) used by TUV for analysis of the exact road performance of the car. Michelin Pilot Sport 240/40 R18 was used as the test tires.

Weight of the wheel tested

Wheel	Weight, kg
ISIDA	8,16
BRIG	8,77
Original cast wheel	14,60

The table above shows that Solomon Alsberg’s wheels are 5.83 kg (minimum) lighter than original cast wheels.

All information required for simulation process was obtained based on actual measurements. In-process measurement data is as shown below.

1. Ease of control

Ease of control hereunder means the force to be applied on the steering wheel when enter a turn. The force is characterized by the torsion torque – the less the torque the easier it is to turn the steering wheel. Consider the situation when the steering wheel needs to be turned 200 to either side at the speed of 140 km/h.

The diagram obtained shows that the torsion torque of the steering wheels has decreased and the time required for a maneuver has slightly decreased as well.

Wheels	*Force to the steering wheel, Nm**
Solomon Alsberg wheels	4,28
Original wheels	4,32

Thus, using Solomon Alsberg forged wheels we have obtained a lesser torsion torque – rather the only quantitative characteristic allowing to state to what extent the control ease has improved.

2. Fuel consumption

This test shows a fuel consumption – wheel weight relation.

The diagram demonstrates that the Solomon Alsberg’s wheel equipped car saves 0.08 kg of the fuel per a traveled distance of 25 km which means an average fuel economy of 0.44 litre/100 km compared to the car with original wheels. Fuel economy will be 2 to 5 percent per year for the average annual mileage of 20 000 km, if use Solomon Alsberg wheels of the nominal size identical to original. Undoubtedly, in each certain case the fuel consumption depends on many factors but it is obvious that the minimum specified fuel economy is true for any case.

3. Environmental effect

Amount of harmful agents exhausted by the car to the environment is in direct ratio to fuel consumption. Thus far, any even slight decrease in fuel consumption results in lesser emission.

The diagram shows the level of СО2 emission per traveled 1000 m distance is less (although insignificantly) for the car with Solomon Alsberg wheels.

СО2 emission per 1000 meter per one (1) year for the average annual mileage of 20000 km

Wheels	СО2 emission, g/1000 m	CO2 emission, verage annual mileage of 20000 km, kg
Isida	368,18	7363,6
Brig	368,53	7370,6
Original cast wheels	373,36	7467,2

The table shows that the car with Solomon Alsberg wheels has a less СО2 emission at the average annual mileage of 20000 km than that of the car with original cast wheels – as a minimum, less 96.6 kg (or 5.3 percent).

4. Car braking behavior

In this case an emergency braking was simulated followed by measurement of the length of brake path from 80 km/h to the full stop of the car with ABS system being off. A brake path appeared to be longer for original cast wheels, than that for Solomon Alsberg forged wheels.
Brake path value (from 80 km to 0 km/h)

Wheels	Brake path, meters
Solomon Alsberg	132,5
Original wheels	133,6

This test has demonstrated a certain trend in car emergency brake behavior when using lighter Solomon Alsberg forged wheels.

5. Acceleration

Given equal (fixed) position of the accelerator pedal acceleration value has appeared to be 4.9 m/s2 for Solomon Alsberg forged wheels, and 4.88 m/s2 for original cast wheels, respectively. Thus the car with Solomon Alsberg forged wheels is capable to accomplish the same distance faster than the car with original cast wheels.

Wheels	Distance covered in 20 sec., m
Solomon Alsberg	519,60
Original cast wheels	516,44

The illustration shows the test car with Solomon Alsberg forged wheels (marked blue and red) leading the test car with original cast wheels of almost 2/3 of the body – and that is as early as after 20 seconds of a ride!

Thus, less weighted Solomon Alsberg forged wheels in all tests have demonstrated certain positive results (quite steadily, too), particularly during acceleration of the car. Any way, the buyer is the one who decides whether to buy light-weighted forged wheels or not. We hope this material would help the potential buyer consider all pros and cons and make a right choice.