The non-road bits are gravel tracks rather than DH gnarl aren't they? If so, WTB Nano 40 front and Riddler 37 rear.
Edit: missed the 650b bit. But 40mm tyres should be fine for gravel. Anything more would be overkill.
@Brommers started
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The non-road bits are gravel tracks rather than DH gnarl aren't they? If so, WTB Nano 40 front and Riddler 37 rear.
Edit: missed the 650b bit. But 40mm tyres should be fine for gravel. Anything more would be overkill.