I was just following the service manuals recommendation for a hotter climate. Recommended isn't always best. A great case is in GM LS engines. Raced them for years. Suggests Mobil 5w-30. UOAs showed massive shearing, metal deposits, and significant weight differences (equivalent to a thin 20wt after 3-5k miles). Been running a 'European formula' (not that it matters, just what it's called) 0w-40 with amazing results in my current LS2. UAOs and observed wear patterns are key. Not the owners manual.
Never be afraid to venture outside of factory fill. I have found that, though the bottle says 'Honda' on it doesn't mean it offers the best protection. After majoring in mechanical engineering and studying fluid mechanics, I dived in to a bunch of research done in with synthetic (Class 3 and true POAs) oils and found a lot of valuable information. I won't bore you with details but the summary is, an engine is not 'designed to use a specific weight' but rather a huge range of weights. Especially with multi-viscosity oils (anything but straight 20 weight, 30 weight, etc). What you want to be sure of is that you're using an oil for YOUR environment and usage. And, equally as important, you make sure you're using an oil that has additives friendly with the metals used in your engine. Avoid pour-in additives like the plague, especially in wet-clutch applications. Most specs that oil follow (JASO and API) make sure that the oils corrosive properties are within an acceptable limit, but additives do not. Be warned.
This is mostly just my opinion, but there oils far better than what Honda offers, but they do make money off the oil they sell. It will always be recommended for that reason. Will it kill your engine? No, stay regular and most oils won't. But are there ways to extend your engines life by venturing out of Honda 10w30? Yes! Don't let fear prevent you from putting something better in your crankcase.

love your bike, protect its guts
PS: Honda is one of the few 'factory' oils that is made in house. Just as an FYI. And is only a JASO MA oil. Has a much lower friction characteristic and a much higher stop time (read: clutch slipping)
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