Hi folks,
I am a new member with a different twist on the cold starting issue on the 09 klx250. I have read a number of threads about the KLX being hard to start when cold and how many owners simply turn the fuel off and let the carb run dry to avoid starting issues after the bike sits for a day or so. I have exactly the opposite problem. If I run the carb dry I end up spending 15 - 20 minutes fiddling with the bike to get it running again. If I leave fuel in the carb, the bike starts right up, no choke, no tipping the bike, nothing! Just starts right up. The problem is I don't ride the bike every day and sometimes it will sit for weeks at a time. I use it when i have a little time to myself on the off road trails near me. I don,t like to leave fuel in the carb that long for obvious reasons. The bike has very low miles (< 1000 miles) and I just cleaned the carburetor due to a clogged pilot jet. The bike is fitted with a big gun exhaust and dynojet stage 2 kit. Seems almost like a vapor lock issue. Anyone have any suggestions?

 

Does your bike have a vacuum petcock?

I only run the carb dry on my 250 if it will be more than a couple weeks.

 

Thanks for the reply klx678,

No, just a simple gravity feed petcock. Once the carb is dry and the engine is cold it takes forever to get the bike going again.Choke on ,choke off, no go. It seems that a good rocking back a forth may help but not enough to keep from draining the battery. My only thought is a clogged breather or vent but after looking all over the carb I don't see anything obvious. Again, the carb was just cleaned. I removed all the jets, blew carb cleaner through the jets and all the passages in the carb body and then just to make sure I got everything I dipped the carb body in carburetor cleaner for 15 minutes.. I rinsed the body in water per the instructions on the cleaner container and used compressed air to blow out all the passages and dry the carb body. Everything looked brand new after being cleaned.

Once the bike has kicked over it starts up immediately within 1 or 2 engine revolutions and no choke. If the engine is cold and the float bowl is full I simply pull the choke while standing on the choke side of the bike, hit the starter and immediately turn the choke off at the first pop of the engine and the bike starts right up.. After that the bike starts first time every time with no drama....

 

The problem got worse over time. It got to the point the bike wouldn't start at all. I pulled the carb and cleaned it again. Then I drilled the starter jet to .018" and problem solved! Open the choke, engine starts up immediately and within 1 minute i can close the choke and the bike idles perfectly.

Great info on this forum and if anyone else has starting issues I can say for sure drilling the starter jet works!

 

Look at your petcock. If it is vacuum operated there should be an ON-RES-PRI On and reserve are self explanatory PRI is prime, it opens flow bypassing the vacuum set up. My 550 Kaw has that set up. If you either don't have RES or do not use it you will have to crank for quite a bit to get enough gas in the carb to fire and run.

Other possibility if you have the ON-OFF-RES petcock is you are not waiting long enough for the bowl to fill after turning the pet **** on.

It really sounds like a vacuum petcock set up, but only you can tell if it is that.

 

klx678,
If I recall correctly, my KLR650 petcock was ON-OFF-RES, vacuum operated, and did not have a PRIME position. I don't think all vacuum petcocks have a prime position.

 

I am at home and looked, there is no vacuum petcock showing on the parts diagrams for the 2009, so that isn't the issue.

I will say I have my starter jet drilled with a 0.020" (#78) drill. Done by hand with a pin vise to drill. Grease on the bit to retain the cuttings. I also have the 40 pilot jet and 2-1/2 turns out on the idle mix screw. Bike stars like it should. If I run the carb dry or drain it I turn on the petcock and take the time to put on my helmet and gloves or whatever, then I go to start after giving a good amount of time to allow the float bowl to fill adequately.

 

My thought exactly. You need to wait 10 seconds for the bowl to fill. Then hit the starter and then pull the choke.

 

My thought exactly. You need to wait 10 seconds for the bowl to fill. Then hit the starter and then pull the choke.

 

Shake it back and forth with the choke on while starting. Works on my '09 everytime! Wish I learned this trick long ago.