Nobody ever said you're not supposed to do warmup sets on Greyskull.
That being said, your working weight is still very low. But try this the next time you deadlift:
bar x5 (you won't touch the ground with just the bar, so it'll be more like an RDL)
85 kg x AMAP
warmup sets aren't just there to warm up; you can use them to practice your technique. Aim for perfect posture, tension and leg drive.