I'd contend that all you're doing is spinning the engine just a bit faster with more battery power which in turn is creating more vacuum to draw more fuel through the starter jet...or...in the case of the KACR reducing compression a little too much, spinning the engine more strongly helps overcome that issue to create more vacuum to once again draw more fuel through the starter jet on the choke circuit. So technically you can say all we're doing with all of these methods of cold starting is getting better fuel delivery during cold start. A hotter battery spins the engine a little faster and more strongly to create more vacuum. A modded KACR where you'd increase starting compression would create more vacuum. Rocking the bike aggressively to stir the fuel in the bowl to raise the fuel level can help fuel delivery in a low vacuum situation. Using a fuel bulb primer mechanically delivers more fuel for cold startup despite low vacuum draw. And finally opening up the starter jet allows more fuel to be drawn from the bowl during choke even with low vacuum.

Now, if you look closely you'll notice the common theme on all of the methods that folks use to improve cold start is improving fuel delivery in some way...even your hot battery method. Here's the problem with relying on your battery power method. If you're on a trip for days or weeks at a time, like the Moab trip I'm preparing to leave for in the morning, where do I get access to a charger when camped in the boondocks? So do I need to jump my KLX battery from my van every morning? The most simple method of improving cold starting is to provide more fuel. The easiest way to provide more fuel at cold startup is to drill the starter jet. While this requires one to open up the carb, the "easy" part lies in the fact that this mod only works when you pull the choke ****, and all you have to do is pull the **** and push the start button. No shaking of the bike...no extra plumbing for a fuel priming bulb...no constant hooking up of battery chargers...no KACR modification.

For whatever reasons we might want to debate on the causes of the cold start problem, I think it's clear that not enough fuel is mixing with the air to allow proper combustion. Proper combustion basically occurs when the proper amount of air and fuel are ignited by a proper spark. Now you weren't clear on this, but if you were suggesting that the spark is the weak link here and that the hot battery is curing this, I'd say that's incorrect. If the starter can spin the engine over, there's enough current in the ignition circuit of the KLX to fire the plug the required amount...barring other problems in the ignition circuit, of course. In those cases of problematic cold startup, the KLX does not get enough fuel during cold start to overcome whatever the debatable issue may be...low vacuum by KACR...a marginally sized starter jet...low fuel level in carb...poor fuel quality or fuel breakdown...low battery...and on, and on.

 

Its not battery related. I am still on the original battery and I keep it topped off with the charger, but trust me if I did't run the gas out the bike will not start and not for lack of turning over. Its spinning as fast as it can, but no go. A long time ago I mentioned that if you have a weak battery or even crank too long because its not going to start the battery will get low fast and not work. Guys you have to keep the battery maintained, but its not the battery's fault that the gas is crap!

 

Delivering fuel in a different way? You mean fresh gas? Then yes. It’s still my theory that the gas in a small carb bowl changes because of the crap it’s being made with these days. Letting in fresh gas before you try to start it mean that you just introduced gas that came from a 2 gallon supply which hasn't had time to change. I also have to admit that there is some inconsistency with the bikes in that some have this problem and others don’t. Some have been able to correct it by drilling out the jet and others it may not have worked for. But before any changes to the carb, I bet that 100% of the bikes could have been started using the run the gas out method. That tells me that the common denominator is.....wait for it.....the gas.

 

You're basically right, deej...it is the gas. But, if you give the KLX enough of even this cheap kerosene, it will start...LOL!

 

If I had these problems with mine, I'd be ready to just get rid of it. I cannot believe how bad some of you folks describe the problem. I bought mine new - I'd have returned it under warranty and had them fix it or keep it...

I'm glad I haven't had a single issue getting mine started from day 1. I'm one of the fortunate few I guess. Mine starts at any temp, no matter how long it's just been sitting.

 

Get rid of an otherwise excellent bike just because I'm not willing to do the simple task of drilling the starter jet? I don't think so.

 

Cold starting
Try this before tearing into the carb:

I have a 2009 and have never had a cold start problem. I was reminded by a poster over at ADV Rider of an old dirt bike trick I used to use with my KDX200;

Turn on the fuel, pull out the choke, put he bike in gear and rock it back and fourth four or five times.Take it out of gear and fire it up.

I've used that procedure since I bought the bike about five weeks ago and have never had it fail. Of course I'm at around 1800 ft and the temp. has always been at least 40 f.

On hot starts, the owners manual says closed throttle but I've found that a little throttle is required or it doesn't want to start.

 

you laugh at kerosene but i was once at one of those bonfire parties which involved too much drinking, lawnmower racing, and dirtbike riding. my buddy had an older xr250 that i had run out of gas. thankfully i ran out right where there were a bunch of gas cans. i took the nearest one and filled er up. 10 minutes later after riding in the woods, we're scratching our heads wondering why the darned thing is pinging and smells like a kerosene heater burning...

 

Thanks "vamcam", I will let you know how it works out on my 2006.
Roy

 

How in the hell could that effect starting what so ever?