Bike Died And Wont Re-Start

[02YZ426]

I was flying down a strait away and shut down on the throttle and the bike died out instantly with about 1/4 throttle revs. Bike was running great up to that point. So far I have checked the valve timing, and all was good there, still has lots of compression and everything seems ok to this point. I cant really see a good spark so Im thinking its electical. I have an Electrex USA stator in this bike and I kinda think that might be the source of the trouble. But how do I eliminate that its not the crank sensor or the ignition coil before I tear out my stator? Any suggestions is greatly appreciated. Thanks

[PumpkinHumper]

Did you try a new plug? Sounds like you are going about the trouble shooting in the correct way. Narowing it down to the spark sounds resonable especialy since you have an aftermarked stator in there.

Did your stator come with the backer plate or did you have to assemble the windings on your stock backer plate? I had one of theres a few years back that you had to assemble there windings to your backer plate but I see that they offer it with the backer plate now.

Reason I ask is if you had to attach the windings to your stock backer plate maybe one of the wires came in contact with the flywheel and is geting grounded out.

[02YZ426]

Ya, I did try a new plug with no luck.. I know sometimes with these bikes the spark can be hard to see, but I even tried it with the lights off in the garage and I cant get anything. The stator is one that I had to wire onto the backing plate, and from what I can tell all the wires appear to be ok. I am going to try a resistance test on the crank sensor next and see if theres trouble there, but I think its going to be fine. Is there any way to test the ignition coil? I think if the crank sensor is good, I will swap out the stator and if thats not it, I guess all thats left is the coil. I think I am getting on the right track here.. but electrical is not strongest talent.

[targetdrone]

My first thought is that perhaps you sheared the key and spun the flywheel.

[02YZ426]

Ok.. This might be a good one for Grayracer. I took my multimeter and set it to 200k and measured the resistance of the crank sensor 0.3 and I figured that was ok. I measured the resistance of the green-brown wires on the stator and got nothing... So I measured my stock stator and got a reading of 0.8 from the green-brown. I think seeing as I can get 0.8 on the stock and nothing out of the Electrex USA stator that this is definatly my problem. Am I testing this properly?

[02YZ426]

?? Ok this really sucks now!! I have replaced the stator and still no spark!!!!

I dont know whats going on now, I know that I have a good stator that shows resistace where the old one didnt, My crank sensor is working, now what CDI???? I hope that when the stator went it didnt fri the CDI too. Anyone have some Ideas here??

[PK]

Doesnt the manual spell out how to check the coil? I'm not sure on the CDI, do you have a buddy with a 426 you can borrow a CDI off of? If you can verify the coil is good, it really only leaves the CDI. Have you unplugged the connector on the CDI and checked for corrosion or water? I would go through every connection and ground point on the bike and make sure it's clean. The resistance check you did on your stator tells me your stator has an open on it somewhere which isn't good obviously. An open shouldn't kill your CDI, a short to ground with the accompanying voltage spike would scramble it's brain though. Check everything including your kill switch. Check the simple stuff first, before you start throwin money at parts.

[02YZ426]

I wish I could find my manual right now. All the grounds are good, I tried for spark with the kill switch unpluged and as far as the coil goes I dont have the specs so I just tested the orange-black wires and it doesnt show an open circut so Im assuming its ok. Im going to track a manual right now.

[2fastwhitey]

Check the connections and clean them with a good deoxid or electronics cleaner. I am assuming there should be and open loop through the CDI. If it is closed I don't think it would start. If the stator is good maybe you have another problem. Did you check to see if you get a good spark of the Stator. I would check this first to know if you problem goes further. Then you know you have to back trace the problem. Find a good ground and check it out. I can check my manual for the 426, I'll grab it and see if I can find something.

[02YZ426]

Well, I finally got my hands on a manual and according to the Problem solving tree I have everything checked except the neutral switch before it says replace CDI. I will check that tonight and let you guys know.

[NYMXer]

It could be anything................lot's of testing ahead but it does sound electrical or out of gas. Try to find a loose connections under the tank. ?

[02YZ426]

I just checked out the neutral switch and thats working fine. Since I know that the old stator was fried and all the electrical components around the CDI are testing OK, I figure that the stator shorted to ground and sent a voltage spike up to my CDI and fried it. Oh well, this is my luck anyway... I will order a CDI tomorrow and keep my fingers crossed. By the way, I would definitley steer clear from ELECTREX USA, since there great product killed my bike. I always wondered about that stator.. I mean how can you take away 2 ignition posts and make them charging posts and not expect problems? They are pushing too much power through 2 posts for the windings to handle.. I guess thats why Yamaha uses 4 posts for ignition, it handles the power better. Lesson learned, and never again will I run an aftermarket stator. Thanks for all the suggestions guys. ?