Not enough spirit Cast on Shock / Temporal Rift

I have 95 spirit reserves and it says I don't have enough spirit for cast on shock, which is 60 spirit. I think there is a bug with temporal rift reservering more spirit than it says, its only with cast on shock; if I enable Mana Remnants with support gems, I can use over 60 spirit (Mana Remnants + Clarity + Vitality).

Does anyone know a work around around this bug? Socketing spells or changing weapon sets doesnt help either.

having the same issue

bmp

Try putting "arc" into the support gem slot and see if it works from that. Worked for me and I can now enable it.