Be aware of the heat you are subjecting the oil too in hot periods is good on air cooled bikes, a fresh change sometimes can be felt. Our bikes gearboxes are tough on oil so changing the oil more frequently in extended heat or before or during a hot spell can help these air cooled bikes. I live in the Tucson area and we have months of triple digits heat in summer so I change before summer and ride water cooled bikes with at least semi synthetic oil with grade to handle the heat. An air cooled bike depends on the oil and air to cool it...so the air cooled bikes are for less intense weather, besides, the water cooled bikes is also fuel injected and faster and more powerful, so I'm not staying out in the heat more than I have to be. The cooling vest quickly dries quicker and my tolerance for 105 and above temps and my safety goes down due to the heat exhaustion risk. 30 minutes to 45 minutes is fine but better to have shorter trips in extreme heat if you have to do it. That said, I intend to fit an oil cooler on my cb550 when I rebuild it to give it the ability to handle the heat better. I just need to improve my own tolerance for the heat too...