When the air temp is below 50d, I let it idle 5 minutes before riding. Above 50d, 2 minutes. Then I watch the dipstick temp guage and take it easy till it reads 100d.
with my carb I do about 3-5 minutes I guess. Start it up, take it out of the garage, close the garage, put jacket and helmet on and head on out. Push the choke in before I take off.
I leave my home for work at 4:30 AM..If I let it idle, I will wake up the neighbors, and that I do not want....I start the bike at the end of the driveway (rolling start) put into gear and idle out of my neighborhood. Then I take it easy for a couple miles.
Been doing this for almost 60K on this bike, and over 40K on my previous bike, with NO issues at all, even in colder weather.
When the air temp is below 50d, I let it idle 5 minutes before riding. Above 50d, 2 minutes. Then I watch the dipstick temp guage and take it easy till it reads 100d.
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Pretty much what I try to do. Main thing is never just crank a cold bike and go. It won't hurt it initially, but from what I gather over time it can make the difference between a 90K bike and a 190K bike. Assuming you keep it stock.