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Okay guys I could really use some help on this one, I've been diagnosing this bike for almost 2 months now without success. I've spent hours on the phone with a technician in Anchorage, time searching this forum, and in the manual as I live in an area of Alaska without a dealer/ tech.
2012 KX450F set up for a Snow Bike kit I just bought this year haven't had one ride.
Problem after checking valve lash bike developed difficulty starting. (Here we go I've checked the valves they are good to go triple checked...., the bike runs fine the issue is starting.)
At this point the only way I'm able to start the bike is by unplugging the capacitor and hooking up 12V battery, if I dont do this and allow the fuel pump to prime at least 1-3 times bike will not start.
Things I have checked so far...
Valves in spec
Fuel pump flow test in spec
Fuel pump pressure test in spec
Stator Magneto output in spec
DFI self diagnostic gave a water temp sensor code (replaced and didnt solve)
Fuel injector ohm tested in spec
Voltage to Fuel injector in spec
Crank sensor in spec
ECM replaced (didnt solve problem)
Regulator Rectifier 12-13V output which is not in Spec (14V-14.5V) but dont suspect that to cause this problem?
Spark Plug replaced
Capacitor tested passed OHMs test
Ground to ECM in spec
I bought wiring harness, ECM, Capacitor, Regulator Rectifier, Ignition Coil that were taken off a running bike plugged and played did not solve problem. (I have not replaced the wiring harness with the one I bought)
Whats your thoughts on what to test next? I've probably missed things I've checked at this point. My thought is to start back at the beginning this thing is really exhausting my patience. Anyone think I need to buy a new Regulator Rectifier based on the 12V-13V output. I've spent about 500$ on parts so far and hate to keep buying more if not needed.
Thanks in advance!
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Black Ops Moto
I just got done totally rebuilding a 2014 kx450f I mean all new everything on the inside of the motor. But now the bike won’t start on its own. But it will start with starting fluid and then it stays running untill you shut it off. Could my fuel pump be going out or could my ECU be bad? Iv had different people tell me different things. Bike also has a bit of a misfire when your trying to keep the throttle locked at a certain point. This is my first fuel injected dirtbike and I’m not sure what to check first and or how to check it. I put a lot of money into this bike and I just want it to run right.
I currently live in Phoenix Arizona and I am having problems with my 2006 KX450F backfire. Its rides perfectly fine and has all the power in the world, does not lack on the responsive side at all. But whenever I engine break I pop A LOT. "Poppopopopopopopopopop" and its whenever I am slowing down after either going fast or slow. I want to know how to stop that, I understand that some popping is okay, but its a lot, spits fire sometimes after going fast.
I am not sure what current jets I have in the bike, because the previous owner did not know, but I am thinking of going to a 180 main jet, 42 pilot, 55 leak jet (from 70 stock), throttle clip position 4th from the top, and 2 turns out on the fuel screw. I have heard a lot of people changing the leak jet from 70 to 55 helps a lot overall. I am not sure on what to use for the elevation wise on the jets.
I have tried to lean and richen the fuel screw before but nothing has happened.
Any suggestions of what I should do? Just thinking of getting JD Jetting kit and going from there.