The fibres were sub-sequentially twisted by mechanical friction on the surface of the drums.

The fibres are subsequently twisted by mechanical friction on the surface of the drums, which rotates in the same direction.

Which reduced all mechanical friction to nothing.

Which reduced to nothing all the coefficients of mechanical friction.

Tribochromism refers to a change in colour of a material caused by mechanical friction.

Tribochromism - color change caused by mechanical friction.

If a dual-cable setup is used, mechanical friction is reduced.

In addition to mechanical friction, considerable force is required to overcome the valve springs used to close the engine's valves.

Instead, these forces are applied between the vehicle and the rail, reducing mechanical friction and wear.

The second strategy was to reduce mechanical friction by using an offset crankshaft and other technologies.