Does this bike have a wet clutch (shared sump)? If so, you should use an oil that meets JASO MA spec. I'm not aware of any 5w30 oils that meet JASO MA. There may be some heavy Xw-30 oils out there that are not energy conserving and that might be OK, but I would suggest you stick with 10w-40.
In the manuals I have seen, they allow 10w40 or 10w50. I have used 10w50 in my Triumph as the shared sump system tends to shear the oil and make it end up in the 40 weight range in relatively short order.
My Triumph manual recommends Castrol RS 10w50 specifically.