I installed the 160 in mine & the fan does run a whole lot more, but then that's its job & that's why I bought that switch: so the bike runs cooler.
FWIW, I simply removed the old one & screwed the new one quickly in with no particular burping rituals afterwards (beer excepted). A little coolant was lost, but I topped up the reservoir with what looked like an equivalent amount & went riding.
Check your reservoir level with the bike cool, top up if necessary, and let the fans do their work. That's what they're there for, especially idling stationary in Singapore.
Happy trails & welcome.
'7? Benelli 650S, '80 BMW R100 RS, '07 KTM 990 Adventure