RM-Z450 help

[sp1tekiller]

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?

 

[sp1tekiller]

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.

 

[sp1tekiller]

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.

 

[lwsmithjr]

Colder temps usually means a bike runs leaner, not richer. Open up the fuel screw 1/4 turn and see what happens (Just in case -- the fuel screw is located on the bottom side, on the front of the carb.)

 

[LVDirtJunky]

I also have the 05 RMZ 450, I always give 3 turns of the throttle before i kick it for initial start when cold and it starts fairly quickly, no gas while kicking, I also did not have to mess with the carb, but climates vary. I did notice that if I dont turn it a few times it is a lot harder to start and then i realize that i didnt and turn it a few times and again it start right up, like smith said, since its backfiring the adjustment would only help starting the bike.

 

[spydermat]

idling?

Did you end up finding out what makes it idle like this? Mine does exactly the same thing but stalls when it drops.

 

[RMZRyder]

My RMZ starting profile seems to be fairly simular, choke it 3 throttle twists and kick it over with no throttle and it starts within 2 to 3 kicks. I think any other problems would be related to jetting. Mine was aparently set up perfectly for the mid west were I live. I have experienced no other problems. I have noticed that if you do not kick it over with the full range of the kick starter it will almost never start. Im sure you fellow 4 stroke guys already know this. It seems to be real common among my 2 smoke friends that get on my bike (while running cause I know they cant start it) and stall it and try to start it with a half of a kick like on their smokers. Thumpers take the full stroke.