KDXRIDER.NET

When I first got my bike (KDX 200 2006) it would start 2nd kick with no throttle. I've been working through the new to me KDX list. I replaced the plug with the stock ngk, it was running an 8 (hotter) then I did the first part or the jetting guide, setting the air screw and idle. Since I adjusted it it's needed more and more throttle to start it as well as choke.Yesterday I tried to start it after it had sat for about 10 days but it wouldn't start at all. I took the plug out. It was wet from the failed starting but apart from that was brown. I put in a new plug and it started in just a few kicks with some throttle. Generally the bike runs well (as far as I can tell with my limited experience) it's smokey when warming up but leaves no spooge on the pipe after a couple of hours riding.

I'm wondering if I'm running it a bit lean hence the need for throttle at start up. Any other suggestions?

Thanks,
Hama

I do believe the BR8es is the stock plug, BR9s where only called for in the 93/94 model years, but still shouldn't cause starting problems.
When I did have this problem with one of my bikes, it was telling me that it was time for a rebuild. The Electroplating was simply worn out and the rings a bit tired. Have you ever taken the jug off to inspect the cylinder and piston?

I think the BR8ES is the stock plug for 1995+ KDX's. (9) for the older, faster models.

As always, clean the carb, check air filter clean/oil status. Try draining out that old fuel and starting fresh.

Thanks for the replies. Fuel is fresh. Air filter freshly cleaned. That just leaves the carb. What ever the number is I'm now running the correct plug.

How often do you guys change plugs? I know most two strokes regularly need fresh plugs, but I've never bothered changing mine in my six months of ownership. My bike has also started to get hard to start. Only has around 60 hours of riding on it. Did a big 200km/7hour ride the other day. Plug seemed fine, but I still run an old stock one. I have a few 8s handy. After a good air filter cleaning, should I also change the plug just to be safe? Haven't cleaned the carb in a while too though.

What's strange is that it has trouble starting at random times. Usually when "cold". Never had that problem before.

RustyHama wrote:Thanks for the replies. Fuel is fresh. Air filter freshly cleaned. That just leaves the carb. What ever the number is I'm now running the correct plug.

"Yesterday I tried to start it after it had sat for about 10 days but it wouldn't start at all."

How fresh is fresh?

I usually put a new plug in at the beginning of the racing season, just to be on the safe side. I forgot to do that one year and still had no problem. I run a NGK B8EG.

Jason wrote:

RustyHama wrote:Thanks for the replies. Fuel is fresh.

How fresh is fresh?

I didn't really think about that. The fuel was the last out of my jerry can so it was possibly 3-4 weeks old.

A quick correction. The plug I'm running is the NGK BR8ES as per the service manual. When I got it it had a BR9ES. Why would you choose a cooler plug?

On the subject of fresh fuel. This is interesting but has no definitive answers. http://www.thumpertalk.com/topic/365415 ... -gas-last/

I am thinking you are a bit rich somehow, and you get more air when you give it throttle. Could be the float is set too high, or leaking gas when sitting. Are you using a side stand? Try parking it on a stand that keeps it level.

Adjust air screw to allow more air

You say you did the first part of the jetting guide, did you finish? Jetting is a process and you need to follow it to the letter for best results as most on this board can attest to. I have had my bike sit for months with fuel in it and it still kicks 2nd or 3rd try, even with an old plug from last year. Take the time to do the jetting right (after making sure everything is mechanically sound) and you'll have more luck.

gsa102 wrote:I am thinking you are a bit rich somehow, and you get more air when you give it throttle. Could be the float is set too high, or leaking gas when sitting. Are you using a side stand? Try parking it on a stand that keeps it level.

I do use the side stand in my garage. I have to turn the fuel off otherwise it leaks. It also pours out when the bike is on it's side after I fall off. I'll check the position of my air screw and maybe wind it out quarter or half a turn next time I'm out and see what happens.

It's always best to turn the fuel tap to OFF when the engine will not be running for more than a few minutes.

That said, with the fuel tap on, the engine not running, and the bike standing vertical, you should not have fuel leaking out of the carb. If you do, I would check the float height for proper setting, and also the condition of the rubber float needle tip and brass seat. If these are worn or not correctly set, you will always have leakage when the fuel tap is turned on.

Of course, you want to be sure the fuel tap itself is not leaking through when in the OFF position.

Good luck. Hope this helps.

^^^^^^ what he said! Sounds like it could be your float needle is sticking .

could also be frayed reed valves or crankshaft seals needing replacement

Jet it correctly for sure.
Close petcock when done riding. I do it with the engine running, and kill it when the first sign of empty bowl appears listening to the engine.
Prior to starting cold next time, open petcock, and tilt bike way down on right side until the carb pees. Upright bike, choke, kick.

Just a quick correction... I must have written some of the above on opposite day. I got myself all confused about the plugs, the BR8ES is of course the correct plug for the 06. So I took the 9 out and put one in!
Also thanks to some of the info above I decided to clean my carb. Both jets especially the pilot had some crud in them, I just blew threw them then cleaned every thing with carb cleaner. It wasn't difficult at all. Every thing in there was stock so I set the air screw up stock too. I rode it this morning and it started 3rd kick from cold and ran quite differently, more low end torque and generally more power before the valves open up. So cheers to everyone who posted above!