Notable Dalit Sikhs:

Bhai Jaita - Brought the head of Guru Tegh Bahadur to Anandpur, where a young Dasam Patshah would proclaim "Ranghrete Guru ke Bete" (the Ranghretas are the sons of the Guru). He would later become Bhai Jiwan Singh and fight bravely at Chamkaur.

Bhai Garja Singh - When it was thought that Sikhs had completely disappeared from Punjab, he along with Bhai Bota Singh would write a letter to Zakariya Khan telling him to come face them. Armed with wooden clubs, both would give their lives fighting the Mughal detachment

Bhai Bir Singh Ranghreta - In the 1730s, Nawab Kapur Singh would organize the Khalsa forces into 5 divisions, with Bhai Bir Singh Ranghreta being in charge of one of them (the Mahzabi Dera). https://twitter.com/JungNihang/status/1141135614240284673

Bhai Nibahu Singh - In a battle with the Mughals near Eminabad in 1746, he would climb the elephant on which the faujdar Jaspat Rai (brother of Lakhpat Rai who led the Chhota Ghallughara) was sitting on and behead him.

Giani Ditt Singh - A renowned scholar and reformer from the Singh Sabha period. He would publish many works covering Sikh history.

Shaheed Bhai Beant Singh - Would avenge Bluestar and kill Indira Ghandi