Your challenge is to screw Russia even harder from 1890-1920 compared to OTL. Use any POD within that timeframe.
1. Russia is the same OTL until 1914
2. OE avoids any war since 1911 and remains neutral (important for later)
3. WW1, Russia experiences same defeats and revolutions
4. OE joins on Entente side, also helping to secure certain parts of Russia from the Communists
5. Lenin, Stalin and Trotsky die between 1918-1921 before the Bolsheviks achieve total victory, leaving them in chaos and good for the Whites to resist the Reds
Why is points 2 and 4 important? If there is one nation who has a lot to gain from a mauled Russia it is the OE. They can't achieve lasting things if they fight on the side of Central Powers and lose, they achieve even less if they experienced the defeats of 1911-1913. This is, "a screw as hard as possible" after all. This Ottoman Empire would encourage Central Asia, North Caucasus and even Ukraine to resist against a divided Russia, be it Kolchak's Russia or be it the Bolsheviks. Especially by getting the Russian forces out of the Caucasus and Black Sea region in favor the North Caucasus puppets and whatever regime rules in Kiev (Ukraine is a must). Anything beyond Ukraine is something the UK/France has to deal with. If Russia descends into warlordism for at least 15-20 years since 1918 it is a net win. They cannot return to some of their former lands without provoking a general war.
If Russia sets out of Warlordism in 1933 or 1938 it would take at least three to four decades until it becomes a challenge to Europe/USA (unless a Soviet style industrialism takes place).
The musts:
1. Strong Ottoman Empire with 1911 borders
2. Ukraine having a government unwilling to join Russia
3. The UK willing to let the OE do its thing in Central Asia, Caucasus, Crimea etc. If the UK is against it, it will slow it down or make it impossible. The UK will likely get good deals with regards to oil in the Caucasus, Middle East and Central Asia. A new place open for British Goods, next to British-India seems ideal for London.