Ec300 2015 stalls on high revs

[matanstolero]

Hi guys, after 2 weeks that my ec300 won't run and left with open fuel valve it stalls on high revs.

On low and middle range it runs fine... only when I try to go up to the high range it stalls...

The carb tuning seems to be fine because it never happened before and I didn't change the the jetting.

Thanks for the help.

 

[(F5)]

Stalls in common useage means stops completely. I'll assume you mean stutters badly.

1st off change the plug and consider the plug cap. Ignitions are so good these days its easy to forget plugs can have all sorts of odd faults.

Then clean the carb out carefully. Also check fuel line isn't kinked. In-line filters love to create these kinks in short lines. Check gascap breather.

 

[Davehuge]

Check what F5 has suggested.

Also...

Fuel starvation? Is the carb getting plenty of fuel? There's a gauze filter on the petrol tap inside the tank, remove/inspect/clean. Also check the fuel tank breather in the filler cap is working and isn't blocked, if no air's getting into the tank petrol won't flow out easily.

I assume air filter is clean?

Is the tail pipe clear? I've seen tail pipes blocked with wadding that's come loose. Bikes start but won't rev at high rpm as they can't flow the exhaust gas.

It's simple but can cause some strange effects!

Good luck.

 

[GSGSBrian]

Did you find the problem? I just bought a 2013 EC 300 that is doing the same thing and I am not sure what the problem is. It cuts out at high revs. I set my needle position to the third notch from the top. It was on the second.

 

[Davehuge]

If it loses power over a few seconds and stalls, I'd be looking at a fueling problem, maybe fuel starvation.

If it stalls quickly/sharply I'd be looking at an electrical/ignition problem.

Good luck, Dave.

 

[Dave]

My '03 suddenly developed a severe break up in the mid range and would not rev high at all. Traced it to a failed voltage regulator.

A friend's '05 lost power, the engine sort of bogged in the mid range and wouldn't rev out. The power valve linkage had become disconnected (bolt fell out).

Good luck.

 

[(F5)]

Erm. . So the cdi doesn't use the lighting/ battery charge coils at all so no need for regulator. That would only be the case for a dc powered cdi like an Ignitech. (Not sure about very latest models).
The earthing point for the coil and frame is there though so it could have been the issue.

 

[VilluEST]

Erm. . So the cdi doesn't use the lighting/ battery charge coils at all so no need for regulator. That would only be the case for a dc powered cdi like an Ignitech. (Not sure about very latest models).
The earthing point for the coil and frame is there though so it could have been the issue.

Maybe I'm missing your point but at least '14 CDI is built to use either AC directly from coils (no e-start version) or regulated DC (e-start version). The CDI is the same for e-start and non e-start. My e-start has the CDI coil output, but it's not connected, even though I have completely removed battery and starter.

 

[Dave]

Erm. . So the cdi doesn't use the lighting/ battery charge coils at all so no need for regulator. That would only be the case for a dc powered cdi like an Ignitech. (Not sure about very latest models).
The earthing point for the coil and frame is there though so it could have been the issue.

The regulator had failed and was shunting full alternator power to the frame. I suspect this bothered the earth reference of the CDI. What led me to the regulator was turning on the headlight (which used some of the alternator output) helped the bike rev a bit higher. Simply disconnecting the power lead from the regulator solved the problem until I had a replacement regulator.

 

[(F5)]

Haha. That's a cute fault.