stator question

[84cr125]

Generally speaking, how many volts should be comming out of the stator. I have a weak spark on one of my bikes that i have been trying to fix for a while. Ive replaced the ignition coil, CDI, and all the wires. the last possible thing could be the stator, but i dont want to go out and but a new one and notice it does nothing. Right now without the spark plug in i can get about 2.5 to 3 volts of current. Is that right or should it be higher? I have tried getting my flywheel nut off but im pressing so hard on the back break im worried ill break something. Any suggestions on how i could get the flywheell off wthout breaking anything??

 

[mxdj666]

you need a flywheel puller they are super cheap like $15.00 without it you risk breaking something, does the bike run ? on your stator you want to ohm it out to see if its bad your not checking voltage your checking continuity

 

[84cr125]

i have a puller. i need to get the nut off which has nothin to do with the puller..... yes the bike runs but it has a weak spark and i cant kick start it only jump it. ive checked the continuity and its within specs. Ibve heard around that Honda stators chack within specs but they need a little more just to get started. Could someone just disconnect the red and white wires off their stator and kick it over with a volt meter and let me know?

 

[energyrail]

how do you it has a weak spark? have you checked the compression lately?
once it's running does it run normal or does it misfire? Yes check the resistance of the stator. And voltage is potential energy, not current. amperage is current.

 

[84cr125]

i just did a top end with less than 2 hrs on it, i have 175 pis about. it runs normal with no misfiring and ive tried to adjust the timing and its exactly on what its saposed to be. the resistance of the stator is where its saposed to be.

 

[rmc_olderthandirt]

You can't really measure the voltage coming out of the stator with any simple piece of test equipment. The stator would only put out a short pulse and the meter would be expecting the voltage to be reasonably constant so that it can take its time with the measurement.

I would expect that if the resitance of the stator is within specification then that is not your problem.

I am going to echo energyrail's question: What makes you think the spark is weak?

Rod

 

[ZOMBIE666]

Like RMC said, you cant just go out with an off the shelf multimeter and test the voltage from the stator, you can with the supply coils, but the pulser coil (spark trigger coil) requires a "peak volt" adapter or a meter with one built in. dont let the look of the spark fool you, i have had MANY CDI bikes with almost non existant LOOKING spark but they all ran fine. if you can get a hold of a spark gap tester (a spark gap with adjustable gap) if you can get a spark longer than 4mm there is no way your spark is weak. if not just use something WELL INSULATED to hold the bare plug wire (remove the cap) and do a spark gap test to the motor(ground). >4mm your a-ok

 

[84cr125]

i know i have a weak spark because when i take the plug out, put it against my frame(bare mateal) and kick, barely no spark. When i put the plug in and kick i cant kickstart it, i can only jump start it. the pulsar coil is developed on the outside of my flywheel and im not tesating that coil. I am only testing the stator coil. My meter shows the peak voltage or currant as im kicking over the bike.

 

[hot125mod]

even though it has decent spark outside of the cylinder , it may not be as strong as it should in the cylinder because the atmospheric air is a lot less compressed than in a cylinder.

 

[84cr125]

well when i have the plug out it makes sense that the piston moves up and down faster, thus making a bigger spark. But i still have the plug out and kick it generally as quick as if it were in the cylinder i dont have a spark.

 

[76GMC1500]

Is the spark crossing at the gap or is it arcing from the insulator to the side of the plug deep inside. That will appear as a weak/no spark and makes the bike hard to start. You never said you replaced the plug.

 

[84cr125]

ive got like 20 plugs and they all do the same thing. and i know im using the right plug( br9es and br8es)

 

[steve.emma]

it is very hard to diagnose a weak spark however testing the stator output and spark output are 2 completely different things.

the stator output can be measured using a multimeter on a a/c voltage scale, to do this you need to have the stator disconnected from the coil and cdi unit and the bike needs to be kicked over fairly quickly (best done with plug out..).
the a/c voltage will fluctuate depending on kicking speed and to be honest unless you have a "good" bike to compare to (or a lot of experience) then the voltage figure will only be a rough indication.

the h/t spark is generated by the coil which is powered by the stator, spark dwell is controlled by the cdi. the pulsar coil is used to give a timing reference to the cdi. both cdi and coil could also be the cause of weak spark as could h/t lead, plug, electrical wiring and frame/ coil ground connections.
you need to check each of these, especially the frame to engine and frame to coil grounds as these never get looked at and are prone to corrosion.

sometimes weak spark can be diagnosed by reducing the plug gap and seeing if your hard start condition goes away (smaller gap is easier for a weak spark to jump etc..)

also as a last point weak air/fuel mixture is often the cause of problems like you describe, are you sure the carb choke circuit is working etc?.. does the bike have crankcase vacuum leaks?
weak spark would make a bike hard to start but its fairly uncommon and hard to check for, so you need to check the basics first.

p.s. 2 easy ways to remove flywheel nut..... first use an impact gun, or if you dont have one try removing spark plug get some rope/cord that you can feed into the combustion chamber through the plug hole, then as the motor is turned it will jam up on the rope and let you undo the nut without harming the engine. i dont need to say make sure you get all the rope out when you're done do i...... :blah:

 

[84cr125]

ok thanbks for the help, i have a meter that measures a/c voltage scale and i email ricky stator and asked them what it shoud be for my spacific bike. They said it should be 20 to 30 AC volts.

When you say h/t spark do you mean high tension? I have replaced both CDI and coil with know good units.

The frame to engine ground, is that the engine mounts? I dont have a vacum leak seeing as how i just put the cases together witha new gasket and ive stuck the case vacum tube in water and i notice no air bubbles.

I have a impact wrench so ill give that a try but its one of the ones you hit a hammer so im gunna need a friends to hold the flywheel.

Thakns for all you help, im stumped with this. If i dont match the AC current that ricky stator recommends i think im gunna get a new stator and try that out.

 

[steve.emma]

When you say h/t spark do you mean high tension? I have replaced both CDI and coil with know good units.

yep high tension

The frame to engine ground, is that the engine mounts? I dont have a vacum leak seeing as how i just put the cases together witha new gasket and ive stuck the case vacum tube in water and i notice no air bubbles.

yep engine mounts, and as for the coil i mean the frame surface that the coil bolts onto. check these surfaces are not corroded, use some emery paper to clean them.
but im not sure what you mean about putting the case vacum tube in water?? the only true way to measure crankcase leakage is a bit tricky and involves sealing off exhaust and carb manifolds then feeding low pressure compressed air through the spark plug hole, then measuring the leakdown rate of the air pressure in the motor.

I have a impact wrench so ill give that a try but its one of the ones you hit a hammer so im gunna need a friends to hold the flywheel.

NO WHATEVER YOU DO DONT USE THIS!! when i said impact gun i was meaning a pneumatic gun, NOT an impact driver that you hit with a hammer as this would wreck either the crankshaft or ruin the engine cases for sure.
use the rope method to undo the nut, its safer and you only need 1 person to do it.

 

[84cr125]

lol i never thaught of that hitting the flywheel would knock the crank out of alignment and warp it lol. ill try the wrope method.

my method is that you take the tranny case hose and put it in a bottle of vater, if i had a crank leak in the gasket you could see air bubbles in the water. at least thats what i heard.


Thanks for your help.