RM-Z450 help

Since I got my '05 RM-Z450 is has always been finicky to start cold to say the least. When it is warm/hot it starts up first kick but NEEDS the hot start. Without the hot start it will not even try to start when warm/hot.

Anyways, when cold it takes quite a few kicks before it even tries to fire, this is with the choke on, gas on and no turns of the throttle. After about 5 kicks or so, it will usually backfire once when I kick it, then the next kick it will fire. When it fires it kind of blubbers for a second or 2, then I give it a tiny bit of throttle and it will sometimes catch and start, or it will die. If it dies I kick again and it blubbers again. I keep doing that until it catches.

The bike hasn't been running in a week so I went out to start it. Gas on, choke on, about 15 kicks and all I got were 3 backfires. Each one progressively louder than the one before it.

One time when starting I tried to give it a twist of throttle before starting, because my CRF250 loved this. It didn't make a difference really and just seemed to make it backfire sooner.

Does anyone have any suggestions??

Thanks in advance!

UPDATE:

Well I got it going. Took about 10 kicks, and it popped a couple of times. Let it get hot and run for a few minutes. Shut it off and it backfired once after it shut down. There is also a lot of carbon around the end of the silencer. Am I running rich or something?

Well this morning I went out and gave it 2 one half throttle twists and it fired up fairly quickly. I let it get warm with the choke on, then shut the choke off. It idled fairly high with the choke on and kicked down a little without it, but was still a little high. Eventually it would kick down to a low idle where it should be, but as soon as I would rev it, it would idle high again and once again kick down after about 20 seconds or so. When I shut it off, it backfired again. Weird how it's doing that, it never did before.

Well I took it riding today and everything was A-OK. Couple twists of throttle and off she went. I guess I'll just have to twist it from now on.