I don't think it matters that much but if I plan on riding hard in the summer heat with passengers and oversized tires, it would give a little more viscosity at the higher operating temps. I don't think it matter a lot because these engines are water cooled.
I really don't know unless I install an oil pressure gauge. I watch the oil pressure gauge on my Kohler mower, the pressure will start out at 40 psi and drop to 10 when the motor is 200 degrees. If the fan is clogged, it will continue to drop as the temp rises to 230 or higher. It's an air cooled engine so after seeing that, I installed an oil cooler and fixed the problem.