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creed
09-01-2007, 05:04 PM
just bought a race ready yfz. its an 04 with a new piston and new wr450 crank lightened flywheel and kick start. there are only the wires to run the quad no battery or lights. its piped jetted and has a uni air cleaner. vortex ignition. the problem is when i brought it home it ran fine for 2 days then i didnt ride for a day. i decided to move the handlebars cause of hieght, and went to try them out. made it half way around yard and it stalled. tried to kick it and all she would do is roll over. let it set and she would idle fine but as soon as i gave it gas she stalled. so ive cleaned carb (dirty in the top) changed the plug. now nothing just rolls over. i dont know alot about these so please help!!!
creed
09-01-2007, 05:07 PM
piston was just put in 2 days before i bought it stock wr450 piston it also has the cam mod. he said he adjusted the valves when he did it. i rode it easy the first rides. did i baby it to much? do the valves need adusting again?
creed
09-01-2007, 06:18 PM
just checked doesnt seem to be getting spark and this is coil end.
RosquistRacer39
09-01-2007, 06:36 PM
Clean that and check the top of the plug cause they wear a groove in the top. Also check the wires going into the cdi (the black box in front of the hood. If it has a tether kill switch make sure its plugged in and I know it sound stupid but check the run/off switch.
creed
09-01-2007, 07:31 PM
the threads in the top of the plug are worn pretty good. ill check the ignition tomorrow it has a vortex on it and there isnt an on/off anymore wiring is set up for race.
creed
09-01-2007, 07:32 PM
i couldnt see a spark off it when i tried it to ground either. i think its bad. lot of slop in it for the plug also.
RosquistRacer39
09-02-2007, 09:40 AM
If you know somone with a working bike take the CDI off theres and change them to see if it runs. My brother had a vortex and it stopped working, did the same thing as yours.
creed
09-03-2007, 05:48 PM
tried different cdi and coil still no spark. so i started checking wires and found this not sure what its called but was pulled tight by the throttle cable and has a crack where the wires go in. could this cause it not to start?
creed
09-03-2007, 05:48 PM
another
creed
09-03-2007, 06:10 PM
pic with a number on it.
creed
09-03-2007, 07:36 PM
is there a way to test the stator to see if thats causing my nonstart issue?
jshtex
09-03-2007, 08:13 PM
The first question is, will it push start? If it will then it eliminates a lot of stuff so lets start there.
creed
09-04-2007, 11:53 AM
no it wont, i towed it around the yard with my 400ex and all she did was roll over. there is no starter or battery it starts by kick.
RosquistRacer39
09-04-2007, 01:13 PM
Originally posted by creed
tried different cdi and coil still no spark. so i started checking wires and found this not sure what its called but was pulled tight by the throttle cable and has a crack where the wires go in. could this cause it not to start?
That looks like a capacitor. Do you still have your fan? If so that just stores power when the motor is running so that when you fan starts it doesn't suck power from the stator causing your bike to misfire. It wouldn't be the problem. Check the ground to make sure its tight. Where its a kicker, IDK if you cand test the stator or get it to spin enough to check.
creed
09-04-2007, 05:57 PM
thanks i found a nice wire diagram earlier today that shows a setup like mine. i think its the stator if im testing it right its bad:(
predator1
09-06-2007, 11:28 PM
could be a bad tether switch also
creed
09-08-2007, 07:23 PM
yeah checked that to. it has quick disconects so all i had to do was unplug and try.
speedy
09-12-2007, 06:07 AM
Take the Throttle sensor wire out of the thumb throttle housing located on the right side of hadlebars and then try to start it.
(just take it out and try it , no need to uninstall the whole wire)
KENNY HEMMINGS
09-12-2007, 09:04 AM
Originally posted by creed
yeah checked that to. it has quick disconects so all i had to do was unplug and try.

I KNOW THIS SOUNDS STUPID BUT DID U MESS WITH KILL
SWITCH ON THE HANDLE BARS WHEN U WERE MESSING WITH
THEM??? I HAD A YZ 450 THAT DROVE ME CRAZY BECAUSE OFF
THE KILL SWITCH IT WASNT GROUNDING PROPERLY TO THE
HANDLE BARS, SOME DAYS IT WOULD RUN AND OTHERS IT
WOULDN'T, PUT A NEW COIL AND CDI AND STILL HAVE THE SAME
PROBLEMS AND ONE DAY I WAS TRYING TO CRANK IT AND HAD MY
HAND ON THE KILL SWITCH AND MOVED IT AND IT FIRED CUT IT
OFF MOVED IT AGAIN AND IT WOULDNT HIT A LICK???
JUST A THOUGHT??
3RDI
09-13-2007, 07:21 PM
I would investigate the flywheel if I were you. Check it for cracks in the magnets......I've read of alot of problems with the earlier lightened flywheels. If you have access to a stock one or one that you know is good swap them out. Just a suggestion.
creed
09-14-2007, 07:02 PM
bought a new stator after testing it. installed and still could not get spark, then i looked in the oil fill hole and saw som of the fiber from the cover over the wires pulled off and found the white wire going to the voltage regulator to be cut. so i am fixing the wire and putting it back together tomorrow. i will update with hopefully good news.