650/X-2 Electrical gremlin

[Kenny]

Been awhile since ive been on here... I have a 88 650sx that has a starting problem... Spark seems weak... I have the killswitch off of it as im typing this... So i know its not that... Yesterday i took off the flywheel and inspected everything visually... Looks good... Im looking for specs on the electrical components i need to test, i.e., thecoil/cdi unit... Like i said, theres a spark, weak looking, but none the less a spark. Any advice would b great... WFO if ur out there feel free to chime in!!!

 

[Kenny]

So the ski just magically started... Any ideas? Would a weak battery be the cause and whats the charging output supposed to b at the battery?

 

[Kenny]

Well spark is lost again...

 

[Scraggly]

probably the cdi/coil setup.

i think i have a good one buried in the shop somewhere. i could send it for shipping cost if you want to swap it out and try it.

 

[Kenny]

So i put the ski on the charger and bam!!... Fires right up... So i checked the charging system and its only showing 12.5-12.65 volts dc at the battery terminals... When i start it while the meter is on it drops to 10-11 volts dc... Then goes back up to the original battery voltage... So thinkin maybe stator? I went ahead and ordered new exciter and charging coils and ill solder them onto the stator plate when they arive... I did however notice that while revving the ski up the voltage went crazy while i had them on the battery terminals... Any idea?

 

[whooiedog]

OE Voltage regulators are junk on the 650's. Notorious for overheating and causing all kinds of electrical gremlins. The voltage reading while running should be somewhere around 1 volt over 12 give or take, if the battery is in good shape of course. I had an X2 at one time that had a marginal battery and if it wasnt fully charged, it did the same thing. Wouldnt start for anyone, but as soon as you pulled the battery charger off, it would fire right up.

 

[whooiedog]

That being said, I have the testing specs for the electronics in the garage somewhere, have to dig them out.

 

[yamadog282]

Start with the simple stuff.....put a load tester on the battery (make sure it is good) or if no load tester is available put a known good battery on it and a volt meter and it should be reading over 13 volts at idle.....if not then quite possibly a chaging system problem.

 

[Kenny]

Ya i checked everything out... Im getting a really weak spark now and the battery at idle never goes above battery voltage after its been fired... I pulled the flywheel off to inspect the stator and found some nastyness... I ordered replacement exciter and charging coils for the stator plate... Also getting a good ign coil from rags... My secondary windings are reading a lil above spec for ohms...

 

[Kenny]

Ok... I charged the battery overnight.. It starts sometimes... And when it finally starts it runs perfect... The sec u kill it and try and restart... It doesnt start... The starter is a lil hot right now from trying to start it...