Giltyler - if the choke lever on your machine moves to the "on" position very easily, you have the weak return spring. If the lever takes a fairly hard push to move it you have the improved version.

 

Man dont let KAW. lie to you . I called them 3 or 4 months ago . My 650 does it to . I thought it was a needle prob. I see now its a choke prob. KAWASAKI EMPLOYEES WILL LIE TO YOU!

 

My chokes had stuck so much that i had to get in there and unhook them, sure put a stop to the smoke , gas in oil, hard starting problem. Pi$$ed me off that the problem exists period. dont expect kawi to help though, it doesnt exist too them.

 

Had this very thing happen to me yesterday. In fact after fixing it I realized my bike has been running like crap for a while. Went to crank it and had vapor lock, check the oil and it was eye level and smelled like gas. Drained the oil and flushed it 3 times and it cranked right up and it ran like a spotted ape. Keeping the gas off when parked seems to be the trick. Has to be air pressure building up in the tank and pushing the valves open in a parked position. Does anyone recommend running all gas out with the valve off until the bike stops? I wasn't sure if this was necessary or not.

 

If I'm letting mine sit for a few days or hauling it on the truck, I'll shut off the fuel and let it idle for 30 secs.

 

My 02 would fill the crank case with gas ....... miss for a while when started ... sometimes hydro lock...

it was the "choke springs." They are not really "chokes" ( choke off air ) .... they are "fuel enrichment valves" ( adding extra gas
from the float bowl at start up)

It is true that shutting off the gas valve stops the gas from pushing through the open fuel enrichment valves when setting......
however, that didn't help with the other problem, which was that after it got warm, and didn't need the extra fuel ( from the
valve(s) being partly open, and it ran like you were leaving the choke applied. [img]i/expressions/face-icon-small-sad.gif[/img]

Installed the heavy duty springs (nyrocs web page) ..... ALL problems solved. It has been two months now. I have intentationaly
not turned the fuel off even once in that time. It runs perfect, starts easy.... and has only oil in crank case now. ....

and I don't have to turn the fuel off !

thanks Nyroc [img]i/expressions/face-icon-small-smile.gif[/img]

 

I think the extreme pressure buildup (from riding and heat & hearing the loud hisssssssss when the cap is unscrewed) in the fuel tank has alot to due with fuel in the engine oil. With this gas tank pressure, it seems that it could push fuel past the needle valves in the carbs. What I did was unhook the breather hose at the tee before it goes into the checkvalve (located under the fender above the gas tank) , capped the check valve with a vacuum cap. I then connected a 1/4" fuel line to the tee and ran it up under the seat. I also installed an inline fuel filter (with the bronze element) in the new breather line to filter out any possible contaminents. I am now thinking about getting the heavier choke springs , but am unsure if they are needed now? I also have a Honda XR600 dirtbike and the breather on the gas cap allows excess pressure to escape.

 

[quote]
Originally posted by: MotoXtreme
I think the extreme pressure buildup (from riding and heat & hearing the loud hisssssssss when the cap is unscrewed) in the fuel tank has alot to due with fuel in the engine oil. With this gas tank pressure, it seems that it could push fuel past the needle valves in the carbs. What I did was unhook the breather hose at the tee before it goes into the checkvalve (located under the fender above the gas tank) ,...........



IMO ... the tank pressure is only a problem if the choke plungers are not closed completely .....

I have changed the springs..... I do not turn off the fuel ... and I do not have gas in my oil any more.

Futher more ... I have a KFX700 ... same carb system, same fuel tank pressure, do not turn the
valve off ... and no gas in the oil.

 

Hey, I have a 03' prairie with this problem, are one of these the springs you're talking about? Can someone who replaced the spring Look up these parts on kawasaki.com parts diagrams please and let me know, THANks

92145 92145-1227 SPRING,VACUUM VALVE 2
92145A 92145-1450 SPRING,AIR CUT VALVE

 

It's not either of those, you will have to go to the dealer and look on his micro-fische.