Rock stars are supposed to be some of the coolest people on the planet, but they're definitely not immune to suffering from embarrassment — as Joe Perry, Nikki Sixx and Slash demonstrated during the conversation they shared during the waning moments of the Sixx Sense radio show.

The veteran trio swapped Spinal Tap stories after Perry was inspired to mention them during a discussion of the six-string bass riff he wrote for Aerosmith's "Back in the Saddle." "I had to laugh when Spinal Tap came out and they had that song 'Big Bottom,'" Perry chuckled. "It's like 'Yeah, well, I did that.'"

"I think we all had that moment watching Spinal Tap," added Sixx, prompting Slash to share the story of the night he had "the worst gig" after a pre-show viewing of the movie — which he took as an omen and subsequently swore it off while he's on active duty.

"There aren't too many things that get under my skin when we're on the road," said Slash. "Where I'm like 'I won't have this, I won't have that.' But Spinal Tap, I will not have on the bus. I cannot watch that during a tour or when I'm working." "The whole movie — every one of us has lived through that," said Perry. "It's just hilarious. They really nailed it." You can watch the conversation above.

Talk then turned to the infamous sequence in the movie when the band gets lost on its way to the stage, leading Perry to share the embarrassing tale of the $500,000 moving rig they paid for prior to a tour in the '80s — and promptly sent home after a couple of dates because it took too long for the parts of the wobbly stage to come together. Sixx, however, shared the funniest story of all, looking back on his early days with Mötley Crüe.

"Ours was really embarrassing," he recalled, "because when Shout at the Devil came out, we were using the cassette that had this song before 'Shout at the Devil' called 'In the Beginning.' That was our intro tape. We were playing a small theater, I think it was in Denver, and we went to the door — and it was locked. We had to go all the way back down the theater and come around. Well, when we stepped onstage, our sound man was so good — we were so professional — he just let the tape keep rolling. It's playing 'Shout at the Devil' and we don't even have our guitars on. We somehow got in time with the song. That's Spinal Tap."

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