2012 500 exc starting issues

Hi. I have a 2012 year model 500 exc for 8 monthes now. Since iv baught it it had problem to start and each time i want to start it requires long cranking to start.

Since i got it 8 monthes ago i did - TPS adjusments, new spark plug, new in-tank fuel filter, new in-line fuel filter, injector clean up, valve clearance, fuel pressure was verified to 3.5 bar, and last week iv allso did a new top end (new piston and new timing chain) and the bike still have the same long cranking problem.

Bike have 500 houres on it, and last week when i opened the top end the cylinder was in excellent condition, the piston was covered with black carbon layers and allso came up as-new after clean up.

The next part im aiming for and allmost the last one i didnt replaced yet is a new fuel pump.

I dont have any more ideas how to solve this annoying issue, anyone have any suggestions?
Thanks.

Edited by Earthmover

how doe it run once started ? if not good could be an ecu

Runs grate, pulls hard and runs  steady at idle.

If it runs good once started and no other issues, that rules out the fuel pump.imo

Is it just a cold start issue, or any time starting?

 

what map does the bike have and tps setting .   If the bike doesn't start in THREE revolutions. (stop). turn the key off and retry. But this is normally worst case scenario on a cold start.

you also have a cold start knob, but never found a need for it. Have you tried that?

Cold start after night will fire in 3 to 5 revs or so. But once it happened, every start at this day no matter if its stood and got cold again- will require long cranking to start but not always. It can start fast once, and if ill shut it off and start again itll have a long crancking. Id say its 90% long cranking start ups and 10% lucky short ones all day. 

I even rebuilt the starter just to be sure it doesnt revs slowly and causing the problem. The brushes was worn and now it runs strong but the problem of long cranking remains.

Euro map desmogged and tps sits at 0.630, thats the happiest spot without backfires and strong power delivery. Crancking gets even worse if im getting under that 0.630

Today i even changed my air filter oil brand thinking maybe the old one was too thick and blocking some air, still the same problem.

Edited by Earthmover

Hummm, definitely not what I consider normal, I consider the ktm 500 one of the easiest start bikes ever made.

 

I ve ran belray, a predust filter and sand filter In certain conditions, and still no effect with starting, that's just a Note.

 

So what you have going on, and the fact it runs perfect once underway , says to me the bike has trouble reading the start condition for some reason.  Cause fuel pump, crank sensor, coils and such, would act up under normal riding.

 

Have you tried an ecu reset, removing positive cable for few minutes and going through the 5 minute initialization procedure, No throttle touch, also reset the idle to 12 out from full CCW) before starting, and after initialization, adjust the idle where needed.

Edited by Spud786
13 hours ago, Spud786 said:

...

you also have a cold start knob, but never found a need for it. Have you tried that?

This is a good thought, to at least see if it's fuel system related.  

The real problem with the knob is that it's almost impossible to get to.

Try a few starts with the cold start knob engaged, even when you know that you shouldn't need it, and see what happens.  

 

one other thing , I can think of , is if your throttle plate stop has backed out , or if it has been miss adjusted at some point.

Thanks for the answers guys.

I rode it today and payed closer attention to when it start and how, and i found an intersting lead. If im shutting down the bike and start it again after few seconds itll start right up no matter how many times ill do it. On the other hand if itll stand still for more than 30-60 seconds after it ran, itll take long cranking to start.

Combining those findings with the fact that after night itll start right up, leads me to suspect my injector is leaking fuel into the cylinder after the engine ran and standing still. The fuel pressure in the line stays high for a long period of time and if my injector has dirt in it it will leak fuel into the cylinder after it standing still for more than 30 sec, wich flooding the cylinder.  When im starting it a few second after i shutted it down itll start right up because thats not enough time for a lot of fuel to leak into the cylinder.

It can allso explain why it start right up after night - fuel pressure went down and the cylinder is clear.

Ill take my injector off again and clean it.

Edited by Earthmover

Well

Took the throttle body off the bike today, pulled the injector, cleaned it with pulses and made sure everithing is free-flowing and all the 12 tiny holes are opened. 

Allso cleaned the throttle body itself.

Put them back, went for a ride, and same issues.

Have no ideas left. Might change the fuel pump later on, everything else is new.

On 11/24/2017 at 7:25 AM, Earthmover said:

Well

Took the throttle body off the bike today, pulled the injector, cleaned it with pulses and made sure everithing is free-flowing and all the 12 tiny holes are opened. 

Allso cleaned the throttle body itself.

Put them back, went for a ride, and same issues.

Have no ideas left. Might change the fuel pump later on, everything else is new.

I've had this same issue since about 20hrs. Did all the same steps you have taken and more. Bike currently has about 320hrs on it, rebuilt once and I never did figure out why it's hard starting. The only thing i havent replaced or checked is the fuel pump. I'm due for a full bike rebuild. If anybody can come up with an answer, I'd love to hear it.

check to see if youre clutch is dragging if you are starting in gear. The other thing I noticed that seem to make a difference is forcefully closing the throttle all the way forward while starting. this led me to believe tps could be off, but ive since had my bike remapped and tps set by orange mechanics, as well as trying several tps/idle settings. there was no improvement. perhaps an issue at the throttle body?

 

edit: oh i see you already addressed the throttle body

Edited by TheW0LF

TheWOLF

New fuel pump ordered , not the crazy expensiv oem one but Quantum 30mm Intank EFI Fuel Pump +Strainer For KTM 500 EXC 2012-2018 wich iv read good comments about.

Allso ordered a new in-tank filter altho i allready swapped it, after the parts will arrive i will install the new pump with the new filter let you know whats up.

7 hours ago, Earthmover said:

TheWOLF

New fuel pump ordered , not the crazy expensiv oem one but Quantum 30mm Intank EFI Fuel Pump +Strainer For KTM 500 EXC 2012-2018 wich iv read good comments about.

Allso ordered a new in-tank filter altho i allready swapped it, after the parts will arrive i will install the new pump with the new filter let you know whats up.

 

Hopefully the new pump will yield some good results. I'm a little apprehensive about putting an aftermarket pump in my bike because i go into some remote areas where a failed fuel pump will produce a lot of suffering. Definitely let us know your results.

 

People reported very good resaults with this pump. 
As for OEM vs replacement, when the OEM pump (naturally) comes from an outside pump vendor for ktm im not too worried about a good reviewed replacement.
On the othr hand when i replaced my piston i went for OEM alltho it costed more than a good aftermarket, just because the houres it went through and the mint condition it were in when i pulled it out.
Ill update about the resaults after itll get inside the tank.

Edited by Earthmover

A late update about this ongoing issue.

What else i did since the last massage iv posted here: i did a new OEM piston and rings kit + new timing chain 20 houres ago , and changed the fuel pump to new one + new in-tank filter and IT SILLS HAS THE SAME ISSUE. Long cranking until the bike fires up.

Looks like iv touched, rebuilt, or replaced all the related parts on the bike beside the fuel injector, the coil, and the ecu. 
 

Any ideas? just throw them around maybe something will make sence because this problem isnt.

Thanks.

Edited by Earthmover

Weak spark? Gas tank breather?

Have you tried a lithium battery? Mine would turn several times before starting with a regular battery but fires right up on the first crank with a lithium. Seems like the starter motor draws a lot of current from a normal battery which robs it from the spark strength.

I not sure in reading the thread that you've checked this one basic thing...so here goes...

Is your idle set high enough??...these bikes like to idle high 2,100 - 2,300 rpm...if your idle is too low...it will hinder starting.

I have a 2012 350 XCF-W....it starts OK....not great...but when cold I find the cold start knob makes a big difference.   I know its a PIA to get to...but it certainly helps me.  Turn your hand palm up...slide two fingers UNDER the knob...curl the ends of your fingers up and then pull out.

The other thing that really helps on my bike is, if it won't start... I crack the throttle a tiny tiny bit...as little as possible...maybe about 1 mm....frequently, when I do that it fires right up.

I realize that doesn't address the problem....but at least it might get the beast to start.

 

Good luck.

 

Does it make any difference if you use the kicker instead of electric start ?

I was wondering the same thing..... ;)

Marcoma - spark looks good, spark plug replaced 100 houres ago, didnt made any change, but i just ordered a new one just to be sure.

My battery isnt lithium but its the bigger 7bs not the regular 5. The battery itself is in very good condition and on too of that  iv allso rebuilt my starter 40 houres ago to be sure its not a slow cranking problem. currently i have a very strong cranking so no issues there, it just takes long revs to start.

Travertt - idle is at 1850-1900 as the workshop manual says it should for the 500, but ill bump up the idle to 2000 for the sake of it and test it.

When the bike is cold it starts quick but only for the first time. if it worked for 2 min and ill try again - long cranking. valves are in spec.

As for the starting of these bikes they start well, i know more than 5 different cc sizes including husa's and they all start after 2 3 turns, mine can take 10. as for opening a bit the throttle - it might help but these are fuel injected bikes and should start wothout interfierence and i want to solve this issue.

Jdepp - good question. it takes 5 to 10 kicks to start it, but i allmost never use it so i cant say that once it started after a long cranking i tried the kick to test it.

Today i kicked it when it was cold, took 4 kicks to start uo.

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