Correct me if I am wrong, but in 1917, it was more Marxism rather than Leninism-Marxism. Leninism-Marxism is what Stalin described as the Soviet Union's political ideology after he came into power. Trotskyists see Leninism-Marxism as somewhat of a contradicting theory to original Marxism. So in 1917, the Bolsheviks, although influenced by Lenin's ideas, were more of a fundamentalist Marxist party, because at that point Marxism was the main theory. They believed in organising a centralised party to overthrow the Tsar, which they obviously did. Now the main difference between fundamentalist Marxism and Lenin's theory is the implementation of a Vanguard party to lead the proletariat into a revolution. Marx argued that the people would achieve this on their own, however Lenin chose to go the opposite way, and create a Vanguard Party, led by intellectuals rather than the proletariat. In terms of what they actually believed in 1917, you will have to look at the leaders of the party, rather than a singular Bolshevik ideology. At that point the Bolsheviks had some what merged with the Mensheviks, and you could assume that their ideologies would have some what merged also. So to see what they believed, look at what Lenin, Trotsky, Kamanev and Zinoviev etc. believed in.
Haha, sorry if i'm rambled on there, i hope this helps.
There is just so many different points of view from what I am currently reading. I suggest the book "Comrades - Communism: A World History" by Robert Service, it has a very in depth analysis of the development of Communism