Hi.
A sr5? Like Ibanez?
All the Ibbys I've had/set up/etc, has had really skinny, highly responsive necks.
Even changing the strings to another make without changing the gauge, has sometimes required a tweak of the truss rod.
I'd imagine that taking the B-string out would make the bass unplayable unless the truss rod is adjusted.
Try it, and please report back. I'm sure other people would like to know the result too.
Taking the string off temporarily won't cause any harm, and then You'll know. If the truss rod adjustment is beyond Your capabilities, try to use the B for a thumb rest or something

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Regards
Sam