I have a cbrf3, and the normal starting procedure in the fall was turn the choke full on, get it to start, and then it would idle up to about three grand and then you'd turn the choke off when it was warmed a bit. When I started towards the end of the season, maybe 40 degrees, it doesn't idle up and always wants to die, I am in the process of cleaning my carbs, the jets are all clean and were before I started, so I'm wondering what else could cause that, or if it is normal due to the temperature.

 

temperature plays a big part. My old hot rods I had to adjust em with the seasons to have em run right. My F4 hasnt been all that bad tho, it tends to like cooler weather.

 

believe it or not changing my oil made a ton of difference for me.
went from mobil 4t racing 10w-40 to rotella t synthetic 5w-40 and my bike now starts without the choke in 40* weather.