Mucuk was the head of the Hells Angels gang in Gießen, Hesse, and was found dead last Friday, shot at least 16 times outside the Hells Angels clubhouse in Wettenberg.
His murder raised concerns about gang warfare, as the Gießen gang has for years been involved in a violent feud with a long-established Hells Angels group from Frankfurt am Main. Police are still searching for the culprit.
Tabloid Bild reported that there had been an “internal” fight with Mucuk and two other members of the Gießen gang.
Mucuk's burial on Wednesday afternoon will be held at a Muslim section of a graveyard in Gießen and police are deploying several hundred officers to the location in preparation.
Still, police said they believe it will be a peaceful event. Authorities also expect traffic delays because of the numerous Hells Angels groups arriving by car and motorcycle.
Hells Angels groups in Germany have often been implicated in organized crime cases involving drugs trafficking and prostitution.
In April, a massive brothel in Berlin linked to the Hells Angels was raided by hundreds of police.
Several local groups have been banned, including three different groups in Frankfurt.