CDI issue

It ran under this configuration for 400 hours before it died. I know how these parts work and have tested and re-tested to make sure everything works. Everything is connected correctly. All grounds are good. Getting good voltage from stator. Ignition coil, wire, plug cap and plug all test good. Get spark when I hit ignition coil with 12 volt charger. Get voltage from CDI when I remove grounds and crank, then replace. Voltage from CDI is not causing spark even though voltage from charger does. Battery is not part of ignition system except to spin starter motor. Parts are not mis-matched. Nothing is wrong, everything works and tests perfect except it doesn't work. The last time I replaced everything it worked for an hour then decided to stop. This time it never started. The bike is cursed. I'm done.

Edit reply to mydlyfkryzis: Like I said.. everything has been tested. Continuity is good on everything. Voltage is good on everything. Ohms resistance is good on everything. All wires are good. Everything is good. I have tested, replaced, tested, replaced, tested tested tried and tried. Thanks for trying to help but the bike is just cursed.
 
If possible, check the part numbers on all the parts to make sure they are the same as the ones that worked 400hrs
Looks like you will need a peak voltage adapter and/or analog meter (digital meter sample times are not compatible with some motorcycle electronics)
Search PVA, the ones on e-bay are severely overpriced, you should be able to make one for around $10.00 as it's only a couple of diodes and capacitors
http://www.youtube.com/watch?v=TWsE2tPjHuo

eg
http://www.ebay.com/itm/Fluke-Meter-DVA-Peak-Voltage-Adapter-Testing-Tool-CDI-511-9773NL-/271237214067?pt=Boat_Parts_Accessories_Gear&hash=item3f26ff6f73&vxp=mtr
 
I took the intermediate gear (from the starter) out again and I bump started it, fired up and did a wheelie. Idles no problem. Ran it up and down the street, on the throttle not a single misfire. Still, it won't start with the electric start. I'm getting the same voltage with the new stator as the old (33-43 volts depending on cranking with 2 or 200 amps), and when I built it and tested it it I'm pretty sure the numbers were the same. Then there was that one time recently that replacing the CDI and ignition coil made it start no problem and run for an hour, started 5 or 6 times within that hour. It just doesn't make sense but what I'm going to do is take out all the gears connecting the starter to the flywheel (which are rattling around like I have rocks in the engine..they sit in the bearings loosely when not connected to the intermediate gear) and replace the kick starter (which broke off). So it'll be kick-start/bump-start.
 
Have you put a voltmeter on battery while cranking?
May be a good idea to check cranking amp draw as well
I would try re-fitting the other parts if it starts OK when you oush start
 
I disconnected the reg-rec from the battery and tried it; spark still too weak to fire. Kick-start will be fine, I'll just leave it at that. Thanks.
 
ca1987 said:
tested and re-tested to make sure everything works. Everything is connected correctly. All grounds are good. Getting good voltage from stator.
Click to expand...


First, if you know it all so well, why does the bike not run? Apparently, you're doing something wrong wich you can't figure out yourself. that pisses you off and now you give us the boot..

Second, saying PJ has to leave is a bit dumb, he knows about as much as the rest together....


Now,

It is possible to test OK on all parts individual, but when parts are used together they can fail.
If the bike runs with kickstarter, what happens when you push the starter button when bike runs?

I think its in your starter motor ciruit. If the starter motor is worn (cheap engine..) in some way it could make a ground and that would explain your power loss.

So,start the bike, put your lights/signals/horn on and hit the starter button. Does she die?

Remember, we're here to help.. If anybody needs to leave, it's you.
 
ca1987 said:
I disconnected the reg-rec from the battery and tried it; spark still too weak to fire. Kick-start will be fine, I'll just leave it at that. Thanks.
Click to expand...

Don't do that. Stator will fry. If you can start the bike with kickstarter and she runs, its 100% sure not your CDI. CDI has nothing to do with starter motor, so when they affect eachother, you installed someting veeery wrong.
 
Running the starter motor while the engine is idling has no effect.

Would you tell me why disconnecting the reg/rec from the battery would fry the stator? I'd hate to have that happen (not that I have any reason to disconnect it normally but I like to know as much as I can).
 
If i understand correctly, your charging system is putting out more juice than the rest of the bike needs so that the battery gets charged. If you remove the battery entirely then excess power has nowhere to go. I will eagerly await a correction.

As to your original problem it sounds like your battery and/or starter are done. A starter motor that will spin when there is no resistance from the motor may still fail under load.
 
The alternator (Stator) on a permanent magnet alternator is a current generating device, not voltage. Without a load on it. the voltage on a current device with no load can theoretically go to infinity. But long before that, the insulation breaks down and fries the windings.
 
Yep, I've seen Honda C90 (6 volt system) produce over 90v AC without load (I used to just measure things to see what they would do ;D )
 
Well it definitely should have sparked, then. Very strange..

Rich Ard said:
As to your original problem it sounds like your battery and/or starter are done. A starter motor that will spin when there is no resistance from the motor may still fail under load.
Click to expand...

Battery is good, starter motor is good, cranks engine fast. Used to start it after a single cycle. Just bzz put put put put put.. Now cranking with 200 amps from my charger at like 300 rpm can't get it to fire, but a swift kick works. I'm happy with that. I've got a lever from a CB750 on it; It looks good and works well.
 
Think I'm finally getting it. If you use the starter motor, you get no spark; if you kickstart, you get spark. Yes?
 
That's the way I read it, but, it shouldn't make the slightest difference if ignition isn't connected to battery anywhere?
Has to be a problem with battery or starter, didn't I mention about checking battery voltage when cranking?
Oh, I did ::)
 
mydlyfkryzis said:
The alternator (Stator) on a permanent magnet alternator is a current generating device, not voltage. Without a load on it. the voltage on a current device with no load can theoretically go to infinity. But long before that, the insulation breaks down and fries the windings.
Click to expand...


that indeed. thnx.
 
crazypj said:
That's the way I read it, but, it shouldn't make the slightest difference if ignition isn't connected to battery anywhere?
Has to be a problem with battery or starter, didn't I mention about checking battery voltage when cranking?
Oh, I did ::)
Click to expand...

Thats why i suggested using the starter motor once the engine has been started with the kicker. If it would have died, there was a short...
 
In the electrical sticky, Sonreir talked about Ohm's law V (Volts) = I (Current) x R (Resistance)

The alternator can generate up to about 9 Amps (9 amps x 12.6 v = 108 Watts). Rating is 110 Watts on a CB350.

So, if the resistance in the system is about 1 ohm, you generate I x R = 9 x 1 = 9 volts. Obviously, the resistance must be a little higher in the bike.

So let's look at 1.5 ohm... 9 * 1.5 = 13.5 Volts....Close.... 9 x 1.6 = 14.4 V.

So a fully charged battery in the system with the ignition loads and lights have about a 1.6 ohm resistance total.

Now lets look what happens when you disconnect all loads from the alternator. Let's assume an idle speed and 5 amp of current available.

First 5 amp x 1.6 at idle is 8 volts....not enough to overcome the battery, so we are using the battery for voltage.

Let's assume the resistance is higher...you disconnect everything but the ignition. The resistance of the coil is 5 ohms stock. I am ignoring the fact that the coil is only connected for 1/4 of the cam revolution for the sake of simplicity.

So 5 amp x 5 ohms = 25 volts.....the voltage went up. However, we have the battery connected. As the voltage goes up, the resistance of the battery goes down, that's why we don't normally see 25 volts on the system... So disconnect the battery....Now we would have 25 Volts on the alternator output.

So for experimental sake, lets run the ignition off a separate battery, so the engine can run, but remove all loads..Everything disconnect means the resistance is maximum, infinity in fact....

So 5 amps X infinity = infinity volts....

Nice in theory, but the reality is, nothing has infinity resistance. Even air conducts if the voltage is high enough (think lightning).

So without any load, the voltage will climb until the voltage is high enough to either arc to a ground, or high enough that the insulation of the wire is not strong enough to contain the electric and the stator starts arcing.

Just the science behind the situation.

Also, a current generator will provide a fixed amount of current (under steady state rotation) and the voltage will vary with load (resistance). This is what we have.

A voltage Generator will provide a fixed amount of voltage, and the current varies with load. the battery is a voltage source....it tries to maintain a fixed 12.6 volts, so the less resistance, the more current. A shorted battery, the current goes to "infinity", but is limited because there is some internal resistance in the battery. A shorted alternator will output the amps it can, with the voltage going to near zero.

That why a battery is good for starting. It can provide a lot of amps at a high voltage. The alternator can only provide a fixed amount of amps.

For the purist, there is for instance, internal resistance in the battery that make it a partial current generator, and the same for the alternator being a partial voltage source. But the way they generate electricity had fundamental differences and their behaviors are different.
 
It's a direct generator CDI system or magneto.
Inside generator will be a charge coil (to harge ignition capacitor) with a trigger coil to 'fire' it
As I said earlier, you need a peak voltage adapter to check output of trigger coil, measuring resistance is only half a job
The charge coil should be putting out way more than 12 volts, even at cranking speed.
Reverse EMF when secondary windings collapse will put around 120 V back to ignition module to re-charge cap
I've seen up to 320v coming back from primary of ignition coil on some systems
If you check ignition system with oscilloscope you'll see sine wave with several smaller waves after initial 'spike'
If link works you cn see there is a real high initial spike then a reverse spike then a could of 'wobbles' as curret swaps back and fore
http://www.bing.com/images/search?q=12v+ignition+oscilloscope+picture&qpvt=12v+ignition+oscilloscope+picture&FORM=IGRE#view=detail&id=BEC3D6A229B53583347976B3955A05DEC4D629ED&selectedIndex=10
Battery isn't connected to coil anywhere (or at least it shouldn't be)
Problem is, we are getting some information but not all information.OP seems to have something of an attitude problem and can't accept the fact he's either doing something wrong or there is a fault he hasn't checked for
 
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