Something very similar happened to my '92 Bandit 250 after my mate borrowed it for a weekend and washed it (and blasted the everloving shit out of it with quite a high-pressure hose).
It actually wasn't related to the hosing down at all, the emulsion tubes were worn out and made the bike bog down, unable to rev out and eventually shit itself completely.
I wouldn't be too quick to jump to conclusions, it could always be pure coincidence. Correlation not equaling causation and all that.
You want some advice - lightning strikes once, it does not strike twice!
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