When I'm playing late night gigs, I find that my drumming is generally a lot slower. The timing is consistent throughout the songs, but I just start them slower.

When I'm playing early gigs or had a nap before hand, I'm always spot on.

I guess that when I'm tired, my brain is slower...

Have tried red bull before a gig but that doesn't help.

Does anyone have any techniques to ensure you're always hitting the right bpm?

I don't want to be pulling out a metronome at the start of every song.