07 YZ450 kills 2 stators

[Chipmaker]

2007 has gone thru two stators in 6 months. Has anyone heard of this problem? Something has to be taking them out? Could it be related to the CDI unit????

[Family Man]

I havent experianced this personally. But for 09 yamaha did improve the the stator mounts to make it amore dependable. Maybe you could get one of the newer ones to mount up?

[Mkrase]

What part of the stator died? The charging side or the ignition side? I've heard of a bad rectifier/regulator taking out the charging/lighting coil side.

[Chipmaker]

it was the power generating side, it was not the "trigger" coil.

The 05-08 coil is on a base that is a cut out shape, the 03-05 is on a round circular base. I think the 03-05 might mount in the engine case. But the 07 mounts in the side cover on the engine. The one thats in it now came from my 07 and we put it in my sons bike when his first one when bad last winter.

[grayracer513]

What part of the stator died? The charging side or the ignition side? I've heard of a bad rectifier/regulator taking out the charging/lighting coil side.

There is no rectifier/regulator in the YZF electrical system. There are two circuits in the stator, not counting the trigger coil, but both of them feed directly into the CDI.

I believe that there may have been a "bad batch" produced, as the '07 and very early '08 appear to be affected, but there have not been many '06's involved. The newest stator is supposed to address this.

[Mkrase]

Thanks for the heads up Grey. I was kind of going off the setup on my YFZ450 which is (well...was, before going all DC) AC and DC output. Is the YZF all AC? Does the CDI act as the regulator?

[grayracer513]

YFZ's and WR's are essentially the same system (AC to DC). The YZ's are all AC. Solid state electronics, of course requires DC current, but all current rectification and regulation is done internally within the CDI.

[Mkrase]

Sweet, good to know!