KTM450 intermittent bog/sputter

[GKR]

The Vortex ECM (C3 and PR2) all adjust for elevation change while riding . The the stock ECM only compensates for altitude on a shut down and restart.

 

[byeatts]

the sputter at takeoff off can be cured by running the idle up higher. I find map 1 to pull the highest RPM with non ethanol fuel.

 

[CB_Rob]

I had a similar bog on my 2019 husky 450fx with c3 ecu.
Jarid from c3 said it might be something with the program and reflashed it for me for free.
Just paid shipping.
I'll let you know if it worked come December

 

[Ktm300]

I had a similar bog on my 2019 husky 450fx with c3 ecu.
Jarid from c3 said it might be something with the program and reflashed it for me for free.
Just paid shipping.
I'll let you know if it worked come December

My bike continued to do this regardless of what map I was in. What I think is/was the problem is that when I fired it up, if o was in gear let’s say and the bit of clutch drag caused it to not spin up fast but still fire, that’s when I had the problems. New anti-gravity battery BTW. It would fall flat on its face as soon as I tried to rev it out. If I took the time to put it in neutral when I started it, it would spin up fast when it fired, and then run really good. Kind of annoying, but at least I found some rhyme or reason and consistency, and a way to work around it.

 

[CB_Rob]

Jarid at C3 reflashed my vortex ECU and the bog is gone.
They did it for no charge other than shipping.

 

[daloof]

I had similar issue, consistently would bog and sputter/low power after I would take a break mid ride. During one of the rides we had an engine builder with us, he advised me to check the little fuel filter inside the quick connect fuel line.... I took it out, blew it out and bike ran fine after that... this happened to me for the next 3 rides, he said small amount of water might get trapped in that little filter and not let enough gas through it... ? .. I dunno.

before my last ride I changed out the filter, put in a new o ring and also put a small amount of waterproof grease on the outside of quick release nipple/o-ring... no issues that day & bike ran great, even after a long lunch break.

this is by no means a confirmed fix, Im still fiddling around with the issue but im hoping that solved the issue. If the issue happens again ill look into the ecu (C3 vortex) & consider changing the map or testing the stock ecu.

 

[daloof]

ignore above... rode today, same problem still, going to start looking into changing maps on the c3 ecu or possibly going back to stock ecu to see if that helps... bummer

 

[CB_Rob]

ignore above... rode today, same problem still, going to start looking into changing maps on the c3 ecu or possibly going back to stock ecu to see if that helps... bummer

C3 reflash is probably the fix.
Hit up Jarid at C3 and run stock ecu in the meantime.
Replacing the tiny fuel filters gets expensive after a while.
I did that too.
Even bought new fuel quick connects and bigger filters last year.
This year not a single bog issue.