Quiet plausible... a long time ago i took my motorcycle out for the first ride after a long pause, as soon as i left the town where i live in and a moment before i would yank the throttle open an ABSOLUTELY GIANT (so perhaps a few milimeter) spider crawled on the inside of my helmets visor. I panicked hard, brought the bike to a screaching halt, yanked the helmet from my head and threw it astaundingly far away into the wheat field where i stood next to.

I was lucky, would this have happen while riding at 250 km/h or knee down in a curve... no, i don't want to think about...

Finding the helmet afterwards was interesting enough...