Hi guys,

Basically, I'm very happy with the little Klx. She has brought me from Europe to Mongolia and back and has had to carry a lot. She is Buajahr 2010 and has meanwhile proud 62,000 km on the clock. Accordingly, she has grown very close to my heart. But since the last time she makes problems. Actually it should go on the enduro track this weekend...
I Lise here on what I could observe:

-When I start the engine, the FI and coolant lamps light up, but when the engine is running
-200km ago I replaced the fuel pump because it was broken
- When the engine is warm it goes off and has no power, driving is hardly possible
-poor start in warm condition
-I had to increase the idle speed because otherwise the engine stops
- the gas picks up when warm

What I've checked so far:

-spark plug changed
-Ignition coil changed
-crankshaft sensor measured - looks okay
-air filter tested
-wire harness searched for defects
-electric plugs cleaned
- Search for leaks in the intake with starter spray
- Fuel pump flow rate checked
- I couldn't measure the fuel pressure because I don't have a suitable watch, but when I put my thumb on the line I can feel pressure
- Kill tray on side stand and emergency stop switch checked
-valve clearance before 2000km
-The self-diagnosis flashes at regular intervals. I guess that means there's nothing to report?

I'm getting to the end of my Latain. Maybe the compression of the cylinder is the problem? Since the problem occurs only in operating temperature. I still try to measure the compression. Also I would like to measure the valve clearance again.
I hope you still have ideas what I could check?

 

A couple of things, that plug looks bad.
If you haven't checked the valves since 2000km, I would look at that, it looks like you checked about everything else.

 

So, agree with popping a new plug in. Given the corrosion up high on the plug, I'd also clean and inspect the plug wire connector to the plug to make sure it's not equally calcified. Electrical resistance will increase with heat.

I'd pull the fuel injector and flush that out and check it's connector. I also would need to understand the fuel filter setup on the efi (does the pump have a filter?). If there's corrosion or debris in the tank it could be sucking that up, but if flow is decent it's more likely the injector. Also, make sure the tank vent lines are clear and not creating air starvation or run it a bit with the fuel cap loose to see what happens.

A hot running coil can give issues too, but where you get the efi light I'd check fuel delivery and venting first before electrical.

Lastly, does the bike use oil? If it's not using oil then it probably isn't compression.

 

Drain the fuel tank and put in fresh gas. Plug issues with deposits like that can definitely be a fuel or fuel delivery problem.

 

One other thought on this. Again don't have a efi klx or it's manual. For the efi light to come on, there needs to be feedback to the ECM. So, either it senses low fuel pressure if it has a pressure switch, it detects a wiring issue to the pump and/or injector solenoid or it detects an unremedied lean condition. My guess is that a lean condition it can't fix by adding fuel is the easiest to detect. So again that could point to a clogged injector. If the bike was stalling intermittently at higher revs it could point to fuel pump relay or wiring, but doesn't sound like the case here.

 

If the FI light stays on when the engine is running, the computer is detecting a fault in either an input sensor or a control circuit.
THERE IS A PROBLEM.
You will need to run a self-diagnostic to see what the ecm on the bike is having issues with.
Hopefully, some of the FI owners will chime in on how to enter self-diagnostic mode.
Usually, it will flash the code with the FI indicator light and you can go from there.

 

Can't give you any mechanical advice, but if you've written a trip report on your Mongolian adventure, I'd like to see a link to it.

 

Hi,

Thanks for your support !
Yes, the fuel pump has a filter which I have also replaced. The tank is clean and the fuel is fresh and new.

The self-diagnosis does not detect any error.

Yes, the engine uses a little bit of oil

yesterday I was again at the motorcycle. The Venilspiel is ok. The timing chain tensioner has four more notches, only then it would be completely extended. The compression is about 5 bar. The workshop manual gives a range of 6,7 to 10,5 bar as usable compression. I was almost glad to finally find something... Whereby a closed cylinder or a leaking head is no reason for joy. Out of curiosity I measured the compression again and deactivated the KACR. Thereby I came to 12 bar. I have no idea how to classify the value because there is no information about it in the workshop manual.

 

No expert, but the auto compression release could skew the results since it's spring and centrifugal in its operation. I'd look into doing a leak down test instead with the engine in the correct position (TDC) to make sure the valves should be sealed. It can help to determine whether it's valves or rings depending on if / how much air is flowing by valve(s) vs. out the exhaust. There are some threads where with info on the KACR and when it kicks out related to the MCM setup.