kick start works, electric start doesn't

[AnimalDan]

I have a 2005 WR450F, just bought it used in December.

Everything ran fine the first two trips out. Third trip, looped out on some rocks. Put a crack/dent in the left side crankcase cover and the bike will no longer start with the e-start. Starts and runs fine with the kick starter. Turns over just fine with the e-start but no spark at the spark plug. Clutch switch, neutral switch, starter cutout relay, starter relay, kill switch and the diodes all check out ok and work correctly.

Now get this. When I disconnect the Blue/White wire going into the CDI, the bike sparks and starts up with the e-start. If I let the Blue/White wire into the CDI float (at ~4.5v) or pull it high to 12v, the e-start will spark and start. But if I reconnect the Blue/White wire or ground it, the e-start will turn over but no spark and no starting. The weird thing, in looking at the schematic, the starter button/relay grounds this wire when the e-start button is pushed.

Since everything runs fine with the wire disconnected I have left it disconnected. But I am now finding that the bike is hard to start cold with the e-start. It will kick and fart but no music with the e-start cold. I then kick start the bike and it will then e-start or kick start fine the rest of the day. The battery seems strong and I keep it on a battery tender.

Is the CDI bad? At $230 I don’t want to buy one just to “check it out”.

Is the Blue/White wire an input to the CDI and what is it for?

[todd764]

I have the same problem with my 04 wr450 i just bought. I think the problem is the fuel mixture at startup, if i give the bike a small squirt with the throttle it will pop and fart but usually starts. I only have this problem when the bike is cold and it will start right up with the kicker. i just installed the jd jetting blue needle and a 170 main . It starts a little better but i think i need to change the start jet. once it is running it runs great.

Hope this helps.

[AnimalDan]

It is not a jetting problem or carb problem. With the Blue/White wire connected to the CDI, the kick start starts just fine but there is no spark at the spark plug with the electric start.

[AnimalDan]

Well I have talked with three dealerships, they don't know and just want me to bring the bike in. I think this problem is pretty simple for someone who can read a schematic and understands how the CDI works. Anybody have a resource I could call?