I have had the bird since July and up until about a week ago it would fire up right away every morning. Just a tug on the choke and VROOOM... Lately when the bike has sat and gotten cold (morning or after work 9:30 pm sitting all day) it wontstart right away. Ill play with the choke a little bit and finally hear it start to want to start and after a couple more attempts it will . Is it due to the temperature change or should I be looking out for something more serious. The electrical system does not seem to be drained at all and appears to deliver ample power to the bike for start up.

Also Unrelated, when riding at low rpms 2.5K-3.5K at low speeds 15-30 Mph the bike lurches sometimes and a kind of slapping sound seems to come from inside the gas tank. sounds like the right side and sometimes I can feel it on my right leg. What is that? when revs are up its gone. am just bogging the engine and should I just have it a higher RPMs?

 

have you tried going about half choke instead of full choke? if not, you'd be surprised at how it might help. i had some troubles starting now and then a while ago, and i just stopped giving it so much choke in the morning and havent had problems since.

i never ride the bike under 3k rpm's unless im in deceleration. my bike used to sound like it was bogging down under 3k, but since i threw my exhaust on it rides a lot better at lower rpm's and seems to have more lower end torque now, which is badass.

as far as the slapping, i was guessing it was just your gas until you said you can actually feel it on your leg. it could still be the gas, but it seems your bike would have to be lurching pretty damn hard for you to be able to feel the gas like that. also, its up to you to determine whether or not you think its a serious problem or just riding error. you're the only one who knows how your bike should ride. all we can do is help. haha.

 

Those two things are definitely related, your lurch and slap is a lean backfire, fire dwells in the chamber and ignite the intake charge next stroke, it blows back in the airbox. Also becoming leaner, your choke became leaner as well and it's getting hard to start.
But why it's now lean, have you just installed an aftermarket exhaust or intake, temperature dropped in the morning ?? It makes the air denser and change air/fuel ratio, got to love those carbs
The fix, install a dynojet kit, or if it have been done before, pull the needle up one notch, move the clip down toward the tip of the needle.
I think the stockers can be shimmed too, but that would still leave the mains on the small side. While you have those carbs in hands, a good cleaning is a mighty good idea.