Just wrap your legs round these velvet rims
And strap your hands across my engines
Together we could break this trap
Well run till we drop, baby well never go back
Strap into this Harley-Davidson and we can escape this cruel, cruel town and never come back.
Another possibility: these lines are double entendres, intentionally cloaking sexual language with actual language, while still keeping with the motif of his motorcycle being an extension of himself. Notice the plurality of “engine”.
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