Problem with my buddy’s kx450f

[bruns_85]

[MotoHead]

Not sure if it’s the same issue as your buddy’s but, I couldn’t get my 15 to start for the life of me (and 2 others who tried) when it was a 30 degree morning out. I wound up having to bump start it down a hill to get it to fire up. This was the ONLY time my bike ever gave me this problem with not starting. Its always started for me with just a few kicks. My only guess was it simply didn’t like the cold.

[bruns_85]

Not sure if it’s the same issue as your buddy’s but, I couldn’t get my 15 to start for the life of me (and 2 others who tried) when it was a 30 degree morning out. I wound up having to bump start it down a hill to get it to fire up. This was the ONLY time my bike ever gave me this problem with not starting. Its always started for me with just a few kicks. My only guess was it simply didn’t like the cold.

 

Yeah but the other day we tried to start it up and it was 70 degrees and still did the same thing

[Brad04]

I’m assuming choke is on. Have you tried holding throttle wide open and giving it 4-5 good kicks and then letting throttle return to zero position and giving it a good kick or two?  Could be flooding itself with so many kicks. Are you turning the throttle at all when kick starting it?

[MarioThePlumber]

I have a couple suggestions.

See if he can find a way to support the bike so he can put his left foot on the peg; that way, it's easier to get a full power kick. It's also much easier to kick with boots. 

Make sure the "choke" is pulled out (black knob that adjusts idle).

Also check to see if there's spark. 

Since I don't know if this bike has started before, if there's no fuel in the line between the pump and the injector, it can take quite a few kicks to start. 

[Brad04]

Let us know if you end up getting it started!

[Bernie Nottelling]

if the airfilter is a tad moist... either from freshly oiled or wet from cleaning.. they wont start cold...

[bruns_85]

Let us know if you end up getting it started!

I’m gonna try it tomorrow and I’ll let you know, thanks a lot.

[bruns_85]

I’m gonna try it tomorrow and I’ll let you know, thanks a lot.

On the video I got it to start on min 5:34 but I start giving gas and it dies.. :s

[Brad04]

After being able to watch the video now that I am home,  it definitely sounds like it got flooded.  I bet if you hold the throttle wide open and kick it a few times it will roar to life.  And use choke every time first start up whether its a cold or hot day!  Needs choke.  The bike could be cold blooded, some are some aren't.  You giving it gas soon as it starts and it dies sounds like it was flooded, started to clear itself up, then it just died from being cold and finicky still.  Needs to be choked and warmed up before any rev's happen.

Another side note,  Try to give it a few slow strokes and feel it through the exhaust stroke etc. until you feel it hit TDC compression stroke where it will suddenly get very stiff on the kickstart lever, then give it a good hard kick at that point. I bet you it will fire right up if you do that and hold the throttle wide open and dont let it move at all from wide open (cut off fuel supply and let in lots of air). 

 

And watching until the point you get it started. 5:30 or so, I can tell you didn't have choke on and instantly throttled it.  It definitely will not start without the choke on a cold day unless the motors already hot/warmed up.  The choke will have the idle pretty high when it starts then when you push the choke knob back in youll notice the idle drop.  At that point it should be able to idle on its own with zero throttle and have zero bogs if you do rev it once its warmed up properly.  Do not rev it at all with the choke on, and do not rev it at all when it is cold. That is asking for premature wear on the motor itself.  

Edited December 11, 2017 by Brad04

[S.O.A.N.Z]

put some decent boots on and support it so you can kick it better

[Brad04]

8 minutes ago, S.O.A.N.Z said:

put some decent boots on and support it so you can kick it better

only reason i put boots on when i kickstart any dirt bike is i wear size 13 boots and my foot always jams into the footpeg when i kickstart. i dont feel it with boots on but if i do it in shoes my foot gets black and blue after kickstarting 2 or more times.

[pavetim]

Try to kick it with throttle wide open and then tape your throttle open over night, or leave spark plug out. Have you done any maintenance? What fuel is he using, I ask cause VP U4.4 makes it a bitch to start. Or get somebody to pull start you with a car, if it doesn't start then you have issues.

Edited December 12, 2017 by pavetim

[bruns_85]

After being able to watch the video now that I am home,  it definitely sounds like it got flooded.  I bet if you hold the throttle wide open and kick it a few times it will roar to life.  And use choke every time first start up whether its a cold or hot day!  Needs choke.  The bike could be cold blooded, some are some aren't.  You giving it gas soon as it starts and it dies sounds like it was flooded, started to clear itself up, then it just died from being cold and finicky still.  Needs to be choked and warmed up before any rev's happen.
Another side note,  Try to give it a few slow strokes and feel it through the exhaust stroke etc. until you feel it hit TDC compression stroke where it will suddenly get very stiff on the kickstart lever, then give it a good hard kick at that point. I bet you it will fire right up if you do that and hold the throttle wide open and dont let it move at all from wide open (cut off fuel supply and let in lots of air). 
 
And watching until the point you get it started. 5:30 or so, I can tell you didn't have choke on and instantly throttled it.  It definitely will not start without the choke on a cold day unless the motors already hot/warmed up.  The choke will have the idle pretty high when it starts then when you push the choke knob back in youll notice the idle drop.  At that point it should be able to idle on its own with zero throttle and have zero bogs if you do rev it once its warmed up properly.  Do not rev it at all with the choke on, and do not rev it at all when it is cold. That is asking for premature wear on the motor itself.  

Thanks a lot Brad! I got it to work the choke wasn’t on I did exactly what you told me to do and now it’s starting at the first kick I really appreciate!

[Brad04]

14 minutes ago, bruns_85 said:

 

Thanks a lot Brad! I got it to work the choke wasn’t on I did exactly what you told me to do and now it’s starting at the first kick I really appreciate!

 

No problem. Everyone has to learn one way and I have enough patience to teach as I’m usually the one taught from someone with experience as well. Use the hot start lever to start it too if you ever drop the bike or stall it and it’s acting like a hot pig that doesn’t wanna start. Then release it as soon as it fires up. I figure you’ll need that for the future since you just learned how to start a 4 stroke single cylinder motor.