whinning noise

[aggio]

In December I bought my first ever KDX 200. It is a 1999 and has allot of the mods I've read about on justkdx. I've been struggling through some jetting issues and am just about there. I seem to have allot of oil coming out through the exhaust. My rear fender is covered with it after ever ride. I am using 32:1 pre mix. Since allot of my riding is done with my daughter on her JR 50. I am not revving the engine much. Can I go to a 40:1 or 50:1 pre mix instead? Will this reduce the oil coming through my exhaust?

Last time I road, I was alone and could open it up. I was in 3rd gear and a whining noise started in the engine. Naturally, I pulled in the clutch and slowed way down to see what the noise was. When I down shifted the whining continued. When I stopped with the clutch engaged the noise continued. I also felt some pulling or creeping forward. I put it in neutral and the whining stopped and when I let the clutch out the noise came back and also the pulling/creeping started again. This lasted maybe 1 or 2 minutes and then the noise disappeared. I checked my oil level and it was on the low side so I added some. I took it back out and no noise yet. Anyone have any ideas?

 

[BRush]

Jetting is very rich from the factory. The stock main is a 160, with a 48 pilot. Jetting is pretty individual to each bike but a good starting point for a stock bike would be:

Main: 155
Pilot: 45
Needle: R1174K , 2nd clip from top
Air screw 1.5 turns out (start there, then fine tune).

See the JustKDX tuning guide for more info:

http://justkdx.dirtrider.net/carbtuning.html

Many people (myself included) run in the 40:1 to 50:1 range without problem. Let the recommendation of the oil manufacturer be your guide. Though I should point out that oil coming out the end of the pipe (aka “spooge”) is a jetting issue, not an oil ratio issue. It is perfectly possible to run 32:1 with minimal spooge if your jetting is correct.

Change to a BR7ES plug. You’ll be much happier with it.

Per the “whining”, you should be fine. KDX’s make a lot of noise if you let the oil get low. If you always run a full quart, that will minimize a lot of it.

 

[Moose95]

Aggio, BRush is correct on the jetting issue. I found that 32:1 was too rich for my KDX too, and since I went to 40:1 (maxima oil) I haven't fouled a plug yet without touching the jets. When you go to choose a plug, keep in mind that for NGK's the lower the number the hotter the plug. I run a BR8ES in tight woods with a 40:1 mix without any problems, just keep in mind that you need to clutch&rev sometimes to keep the "spooge-monster" at bay. Lastly, when you tinker with the bike, make one adjustment at a time, then test it.
Happy trials!
-Moose

 

[slcyclerace]

The following works quite well on my 96 KDX: B8ES, Belray 50:1 with Sunoco 94 octane, 152 main, 45 pilot, center clip on stock needle, 1 1/4 out on air screw, Pro Circuit plat. pipe, P.C. Spark Arrester, 12/47 Talon sprockets, Regina Gold O-Ring, M78 Bridgestone. The only reason I change the plug is out of guilt from leaving it in so long. Never foul plugs, even on the slowest, sandiest trails.
As per Brush, run the full qt. of oil . It really quiets down the Cent. advance .

 

[DAVE C]

One thing you might try to alleviate the noise is to try a different brand of gear oil. I had always used Silkolene in my bike, but recently tried the Bel-Ray Gear Oil. My bike likes the Bel-Ray much better! I had a problem with the jumping that you are describing and the Bel-Ray pretty much eliminated it.

 

[aggio]

Thanks for all the input. It’s been very helpful. I’m running a 155 main, 45 pilot and the stock needle in on the first clip. I went out and got a BR7ES and that made a big difference. I’ve noticed some are suggesting the BR8EG. Should I try it? I also got a 40, 42 pilot, and a 152 main I will be playing with this weekend. Next time I mix up some fuel I’ll try a 40:1 mixture.

As far as the clutch noise I topped it off to about a full quart and have not heard anything yet.

I’ve got another jetting issue on my wife’s PW80. Anyone have any suggestions on tuning it? I get great performance up to around ½ throttle, at that point it totally bogs out. Is this the main jet? I’ve already switched to a main jet 2 sizes under, and put the needle on the first clip. Lots O smoke too…..I know it's not a KDX but she's not ready for one yet...

 

[kdxtaz]

Hey aggio, just a thought on the pw80-
My kids have one and I had a problem with the automatic oiler. Fouling plugs one minute and not enough oil the next. I took it off, plugged all the holes, and now run 32:1 premix, havn't had a problem since.