KFX450 Problems Running

[kawi_kx]

I recently purchased a KFX 450R and I am having problems keeping it running. I have no problems getting it started, but it will only run with the choke/ idle knob pulled out. I start the bike, warm it up with the knob pulled out and then when the bike is warm, I push the knob in and the bike immediately dies. If I keep the bike revved it will continue to run, but it dies at idle. I've adjusted the idle knob and nothing works. I installed a new spark plug yesterday and it didn't help at all. I only have about 2 hours on the bike. I've ridden motocross my whole life and this is my first attempt at quads, especially fuel injection.

[adrenalinefreak]

I hope for your sake that yours is not having the same issues as mine...

First, mine had starting issues...would take forever to start..sometimes just push started it which worked everytime

Second, was I went out to the track and hit a small jump and when I landed the quad lost all power, backfired and died! It started back up but just didn't sound right. Got back to my truck and waited for them to get done watering the track. Went to fire it back up and it wouldn't start.

It was trying to start (so it was different than the initial starting problem) So we tried push starting it and it would fire up and then backfire and die or just die. So I brought it back to my work/sponsor (dealership) and they've been troubleshooting with Kawasaki for 3 weeks now.

We adjusted the TPS, butterfly valve, idle speed (which you can adjust with the choke know) not sure if you knew that by turning that know (choke) you are changing the idle speed!

Kawasaki's latest guess is to replace the throttle body (I guess cause mine was way off) but unfortunately its on backorder until July 8th and I got the last one that is coming in on that shipment. So we jumped to the next thing Kawi said which is replacing the ECM or ECU (computer) that should be here tomorrow and I am PRAYING that it fixes my quad so I can get back out there on it and log some seat time!!!

Like I said...I am hoping yours is not going down the same road as mine....you should also check your fuel tank at the botton to make sure it is not leaking...mine was when they were checking it for the problems above...Kawasaki I believe actually has a recall for it if it starts leaking!

If you have any questions you can reply on here or just PM. My email: worcsracer143@yahoo.com or donnae@carterpowersports.com

Hope that helps!
Donna

[adrenalinefreak]

Should also mention that since its been in the shop it will start now but as soon as you hit the throttle it dies....forgot to mention that above...

[kawi_kx]

I hope that I'm not having the same problem! My quad runs awesome as long as the fast idle knob is pulled out. Once the knob is pushed in it dies unless it is being revved. This makes me think the butterfly is not open at idle when knob is in. I don't know much about efi though. I have dealt with carbs for the last 20 years. I need to figure it out before they put efi on mx bikes.

[adrenalinefreak]

That makes sense! That was of the things they had to adjust on mine as well. Actually, mine ran great!! It fired up the first time (cold) but if it died or I stopped riding for a minute and then tried to start it it would struggle but that really only lasted the first few hours on the bike. Then it only happened occassionally, like when you need it the most, on the starting line of my race..lol..had to be push started...

I don't know how to adjust the butterfly valve but I'm sure it explains it all in the service manual! That book is thick! My 400ex book is half its size : )

Good luck! Keep everyone informed...

[LTR450_#67]

Sucks to hear you guys are having some issues like that.

[kawi_kx]

I got the quad fixed last night! The butterfly was not properly adjusted from the factory. It was completely shut unless the throttle was open, therefore there was no fuel air mixture unless you opened the choke/idle knob or opened the throttle. I adjusted the butterfly valve to Kawasaki specs and it works beautifully now.

[kx515]

Adrenaline, I'm having the starting issues with mine as some of you already know. I got a call from the dealer yesterday and they said that they had it where it would start up fine. However, they went to take it for a test ride and it just died and would not fire up!! Sounds really similar to your problems.... I'm going to the shop today and I'll let them know what your techs have tried. Maybe with that info it will speed my process up. It's been 3 weeks with no ride time and I'm still making payments on this beast!!
Adrenaline, please post what your shop finds out and I'll do the same. Maybe with time we can get these issues resolved. IMO, it's still a great quad when it's running..