Cyclists.

This is coolbert:

Signalers in the sense of strictly couriers/runner? But could be and were much more?

Bicycle troops the Russian Revolution.

"Who did the Russian bicycle troops fight?"

 From https://www.rbth.com/ | SEPT 20 2022 | article by BORIS EGOROV.

"Several military cyclists are buried just by the Moscow Kremlin Wall. Even a street in the capital is named in their honor."

This image purportedly showing bicycle troops of the Red Latvian Riflemen. Most loyal contingent of the communist Soviet Red Army. Personally responsible for guarding Lenin. Extreme communist adherents.

"They could approach the enemy’s positions quickly, quietly and unexpectedly, strike hard and no less swiftly escape. In the early 20th century, when cavalry was already a thing of the past, but the era of motorized infantry hadn’t yet arrived, mobile bicycle troops were hugely popular in the armed forces of different countries around the world."

[....]

"On the battlefields of the 'Great War', the bicycle troops were deployed as scouts or signal personnel [couriers/runners]; also, they were supposed to cover [screen] the cavalry and infantry. Thanks to their noiselessness, they launched effective night attacks against the enemy. The command also used them as a highly mobile reserve force to compensate for defense breaches or, alternatively, to strengthen the army’s position in enemy territory more quickly during offensives. Due to their specific nature, bicycle units didn’t typically take hostages [prisoners]."

Reconnaissance, screening, scouting, patrolling, guard duty, messengers. All valid duty for bicycle troops. But as with all unconventional methods, must be used judiciously in modern warfare.

And NO NEED as with horse cavalry to spend a goodly part of the day grooming the horses. Feed, water, check for injury, get shod when necessary. 

Take no prisoners also!

coolbert.