Maintenance adventures of Shadow and his futile battle against the cursed KX

[Shadow]

It seems this technical section will be my favorite one, and in order to not clutter it up with a dozen different threads, I'll keep my dumb questions regarding bike maintenance and repair constrained into this one thread.

So, I've got two bikes, '01 or '02 kx125 and '01 or '02 kx250 which are definitely cursed and work at purely random intervals.

Not entirely sure on the exact model year as apparently both bikes have a VIN that should not exist. 10th digit on them both points them to be a year '90 but that's simply impossible.

The '99-'02 service manual's procedures for L3 and L4 models (ie '01 or '02) are the ones to follow with both these bikes but it doesn't differentiate more accurately which one they might be.

First issue comes with the 250.

I just got the bike back together after taking it mostly apart but now the idle speed is way higher than it ever should be. It's not screaming with full throttle, more in the low-mid range, and adjusting the idle screw has no effect on the rpms.
This is definitely because of something I did or did not do while putting the bike back together, but any suggestions of what might be wrong are welcome so once I start taking things apart, I might have some idea what to look for.

Another thing, told you they're cursed, I noticed that when the bike is on its side, it leaks transmission oil from where the clutch attaches to the motor(see pic). Not a lot, and only when it's laid on its side, but still I'd like to fix that. Now, how severe is this and will it require splitting the engine case, or is there some smart way to go about fixing it?

[SachsGS]

1st question.If you are absolutely certain the carb slide is bottoming and there are no others glitches in that area, start looking for an air leak. With the bike idling, start spraying carb cleaner around the base gasket area and reed cage to check for leaks.Examine your magneto side crankcase seal to make sure it isn't at fault.

2nd question.Remove your clutch cover and clutch pressure plate.Pull your clutch pull rod out slighty and keep track of the clutch rod ball bearing if Kawasaki uses one there.You should now be able to pull out the clutch activator arm, seal and shaft.Pop a new seal on and you are good to go.

[msmola2002]

To confirm the year, the fork diameter should tell you.

the 02s ran a 48mm fork vs the 99-01s with a 46.

That being said my 02 is currently running the 46mm forks off my 99... So if the bike is a bitza that may not help.

Also the footpegs were different on the 02,

99-01


02

[VintageBlueSmoke]

+1 on the carb slide. Sounds like it is not going all the way down.

[Shadow]

Finally had time to take a look at the issue.

Surprisingly easy, had I noticed it earlier I wouldn't have had to remove the carb. The plastic wire cover wasn't seated properly on the throttle side and caused the slide to not go completely down.

Thanks for the footpeg pics msmola. It seems I have an '01 kx250 instead of '02.

[Shadow]

Jetting issues..

With both bikes too.   


First the 125.

Current settings:
Main jet #360
pilot jet #35
Needle 2nd clip from top
Spark plug was a 9 if I recall correctly

Works fine on the track in high rpms, but low to mid rpm range throttle response isn't too crisp, also will foul a plug if not ridden wfo most of the riding time. Rode an 4-5km long enduro trail just two times and it fouled a plug.

And the 250.

Current settings:
main jet #160
pilot jet #52
Needle clip 3rd pos from top
spark plug 9, I think. Will need to check.

Works fine on mid to high rpms but lacks a bit of response on low rpms. Also, my current riding skills don't allow riding the bike in high rpms as it should be and it's starting to foul a plug + losing throttle response even more on the low rpms.


Track I ride at the most is a deep, soft sandy track at about 70 meters from sea level. What's really bad about the track, is that it kicks up a lot of dust that clogs up the air filter in no time making the bikes behave even more like they're too rich.
Using Shell's castor based 2-stroke oil with 1:25 ratio and 98 octane gas.

What would you guys recommend to change on the bikes for fixing the issues?

[Swimr2DaResQ]

I have an '01 KX250 and i am running the recommended jetting settings as per FMF and it works great with the SST pipe. I ride anywhere from sea level to about 2500 ft.
I also use maxima castor oil at 32:1, I wouldn't run a richer oil mixure, these bikes were designed for 32:1 and you could go to 40:1 without risking a lack of lubrication.
If you are running an FMF pipe I would check their site for the specs. The spark plug is also wrong, stock plug is a NGK BR8EIX, the 9's willl work but they run cooler and again it was designed for the 8's. I used to foul a lot of plugs till i got my jetting figured out. Also the Iridium plugs don't seem to last very long, I now use the NGK BR8EG's, they hold up well and deliver comparable performance to the Iridium's. The BR8ES is a decent plug for tuning and getting your jetting issues worked out as it is the cheapest of the 8 series plugs, but they don't hold up as well as the EG's and will not perform as well either. The number designation on the plug is very important as it indicates how hot it runs, the lower the number the hotter it runs and the higher the number the cooler it runs. 
My main jet is a 158 currently and the pilot is the same, needle position is also the same and I don't remember the airscrew at the moment but it is no more than 1-3/4 turns out.
I hope this helps, I've been there too, but once you get it figured out it is a night and day difference!

[Shadow]

Started thinking about that 125.. As it gives off that Booooaaaa sound when giving it gas on the low rpms, which means it's too lean, yet it still fouls plugs in the low rpms, could it be because of too small pilot jet and too much oil in the gas?

I mean, right now it has #35 pilot jet, and the oil:gas ratio I've been using has ranged from 1:32 to 1:25. So, because of the small pilot jet, it's too lean (ie, not enough gas in the fuel/air mixture) when opening throttle from the low rpms, and because there's so much oil and not enough gas, it doesn't burn properly and the cylinder/spark plug keeps getting washed over and over with unburnt fuel/oil mixture.

Could this be the reason why it doesn't work properly, or am I waay off base here?

[chump6784]

I am running the same jetting in my wifes rm 125, different bike I know but I don't have any problem with her fouling plugs and she is very beginner level. The bike doesn't stay on the pipe when she shifts gears. I am running silkolene at 40:1 with 98 octane fuel

[Shadow]

And the curse strikes once again!

Stripped the threads from the gearbox oil change hole on my 250.
Went so bad that a plain thread tool is not enough to fix the threads. Is there any other option I could try before removing the engine and drilling the hole to the next thread size?

[factoryX]

Helicoil?

[Shadow]

Heh, goes to show how little trouble I've had with stripped threads 'cause I didn't even know there was thread inserts like that.
Worth a shot I guess. Thanks!

[TotalNZ]

Helicoil?

x2

[Shadow]

Just my luck. Everything went fine until I snapped that little end bit off from the helicoil insert. Damn thing dropped into the gearbox.
Any good ideas how to get it out without removing the engine or splitting the cases? Tried flushing it out with transmission oil but that worked only on the aluminum shavings.
I can't just leave the bloody thing in there, can I?

[citabjockey]

Tried probing a magnet up in there? And NO, you can't leave that in there.

Just my luck. Everything went fine until I snapped that little end bit off from the helicoil insert. Damn thing dropped into the gearbox.
Any good ideas how to get it out without removing the engine or splitting the cases? Tried flushing it out with transmission oil but that worked only on the aluminum shavings.
I can't just leave the bloody thing in there, can I?