Good whatever time it is for you,

 

From what I understand, Sheer Force negates Life Orb's recoil no matter what. However, it only seems to negate the recoil if the move is affected by Sheer Force. For example, my Darmanitan is not affected by the Life Orb recoil when it uses Flare Blitz (a move with a secondary effect) but suffers the recoil when it uses U-Turn (a move with no secondary effect). This caused my Darmanitan to faint when it should not have in PVP and if it is indeed a bug, please fix. Thanks!

This is how its supposed to work.

 

- "if a Pokémon with Sheer Force holding a Life Orb uses a move boosted by Sheer Force, it will gain the passive damage boost (because it is not activated after the attack), but the Pokémon will not be damaged by the Life Orb." -

 

https://bulbapedia.bulbagarden.net/wiki/Sheer_Force_(Ability)

This is how its supposed to work.

 

- "if a Pokémon with Sheer Force holding a Life Orb uses a move boosted by Sheer Force, it will gain the passive damage boost (because it is not activated after the attack), but the Pokémon will not be damaged by the Life Orb." -

 

https://bulbapedia.bulbagarden.net/wiki/Sheer_Force_(Ability)

So it is supposed to be damaged by the life orb if the move does not activate sheer force?

Yes