Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

Alright, so theres this Kinetic that has stumped me for the past 3 months or so. Let me tell you what it's symptoms are:

No Spark.

Electricity coming from the magneto.

Electricity coming from the CDI unit.

Electricity coming from the High Tension Coil ONLY if it is NOT grounded.

I know electricity is coming from these parts because it reads on the voltimeter. There isn't a bad ground on the system and all points have continuity.

Any ideas? Remember that these Kinetics run Vespa-esque engines.

Thanks.

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

Some vespas lose ignition if the taillight bulb blows.Check that for sure. don-ohio

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

The back tail light was ghetto rigged but we have since fixed that. Still, no avail.

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

has it run since you `fixed' that? Did you wire it back like factory? don-ohio

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

Yeah. Sorry for the short tone.

The wire connecting the ground was stripped and wrapped around the bulb's ground. We took that wire and resoldiered it to the proper place on the light mechanism.

Let me note another thing. If the high tension coil is grounded, no electricity comes out of it. Any ideas??

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

thanks zippy.

We were sent the wiring diagram ages ago by the cosmo tech support. Although the wiring is a huge birds nest of complicated mess, there still is a simple circuit for the ignition that is solid on this bike. Still, no spark.

Has anybody gotten the magneto off these engines? What's inside that disk of doom beside coils and wire? Anything else? I know the CDI is external but could there be anything else in there that might be failing?

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

it sounds as though you have a short in the secondary winding in your coil or not enough amperage to fire it, if you can get your hands on another coil to try, it seems if you have power to the coil and it does not fire the coil would be the problem, also is your voltage to the coil constant or switching on and off with every revolution as it should be? its a lot easier to test this with an analog meter than digital.

Re: Stupid TFR Kinetic (Electrical Problems)

Don't mean to aggravate you by asking dumb questions but it's just process of elimination since we are doing this via the net.

Have you check the ignition switch wiring in the head light casing. I think there are three wires (a couple of blacks wires and a white or vice versus) Make sure one or more of these are not loose.

Is the Start/Run switch on the right handle bar on? Does the wiring look OK in and out of the switch (not hacked)?

Have you tested continuity thru the spark plug wire? Could the spark plug cap not be screwed on tightly?

Have you pulled the spark plug cap, inserted a NEW plug and see if you can get it to spark against the bare metal of the cylinder head (about an 1/16" away from the metal)while it is being pedalled? Use insulated pliers to hold the spark cap to the cyl head.

There is also a voltage regulator (another small balck rubber module) but I believe it is only for the headlight and turn sigs and should not affect spark. The CDI and Voltage regualtor set on the right side of the bike.

Check the wires coming out of the motor casing to make sure there is no bare wire grounding on the motor casing.

I haven't pealed open a Kinetic but they are the same as the Vespa except the older Vespas have Points and condensor and not a CDI, so the only thing under the flywheel should be two coils (one for ignition, the other for lights and horn) and the wires leading out the the CDI and the lighting distribution wiring harness.

Sorry for the dumb questions, but I'm an old engineer and I never Assume anything.

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

Thanks Zippy and Wiffleball!

Zippy,

All of the wiring to the key ignition as well as the kill switch is as tight as a drum. It wasn't when I first got to it but I've since fixed.

About the spark plug cap, I usually always take off the spark plug cap and just strip a small amount of the insulation and test the wire itself. The reason? Less resistance and I can usually pin point whats wrong from there.

About the wires coming out, I'll have to double check to make sure that the insulation didn't rub off or anything like that.

Wiffleball,

Like I stated before, I take off the cap, strip some wire and test that way. If I getting really desperate, I'll actually hold the bare wire to the cylinder with my hand to see if there's ANY current. Usually, I'll get a zap and I'll know there's SOMETHING. With this bike, nothing.

Also, I have a trick where I use a battery and momentarily touch the wires from the battery to where the points (or cdi) connects, this will cause a spark. And in this case, it does! So, my reasoning is that the magneto is just not generating enough energy.

What I need to know is how to check the amount of energy that is coming out. What do I set the voltimeter to? I know how to check continuity and a rough way to see that energy is coming out of the magneto, CDI and High Tension coil. I need to know the setting so that I can give you specific numbers and can be more accurately diagnosed.

Thanks for your help, both of you

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

Jake I'm going to take a "Swag" at what it is. I think it is the CDI unit. If you have voltage coming from the magneto, the CDI, and coil then I think the electronics in the CDI is not closing/opening properly to cause a voltage spike to the hi tension coil. I don't know what volts should be coming out of the CDI when you are pedaling but it should be a heck of a lot more than 12 volts (maybe 10 times that much or more)

It still could be a pinched or faulty ground. You could try calling or emailing Cosmotors and see what the failure rate is on CDIs. From what I've seen, CDIs rarely fail but if someone did a hacked wiring job before you got the bike, they could have fried some electronics.

Like I say at this point, a Scientific Wild Ass Guess.

Re: Stupid TFR Kinetic (Electrical Problems)

I have also been working on this moped, and i have my own theories. It is my understanding that CDi ignition takes a reading from a pulse device in the coil, and based on that pulse sends a jolt through the high coil and spark plug. I've read that these pulse senders or whatever they're called can be fouled with iron dust and lose the ability to read the magneto position. This is why i think the kinetic won't spark.

is this a fool's errand? Has anyone looked inside the magneto of a CDI system?

Re: Stupid TFR Kinetic (Electrical Problems)

Have you guys tried just straight up replacing some of these units?

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

Yeah,

we replaced not only the CDI but the High Tension coil. The only other step would to be to open up the magneto but we don't have the tool and other ghetto tools (i.e. gear puller) won't work.

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

No, I meant the whole moped. --just kidding. This thing is insane...I wonder if it's another Kinetic quality control issue.

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

actually, we considered sending it back but the schmoe didn't send in his warranty card and thus it is not being covered by Cosmo.

Doh.

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

You can get the metal magneto cover off without using a puller. Remove the engine and lay it flat on padded surface (cardboard or any padding under the engine) with the shaft side up.

Use a rubber mallet and whack the metal flywheel cover on the outer edge to dislodge it slightly from being seated on the center shaft. Wear a pair of work gloves and grasp the fly wheel cover on each side and wiggle it up the shaft.

You may have a to whack the cover a couple of times in different spots but make sure you use a RUBBER mallet.

I remove the magneto cover on Vespas mopeds this way all the time and never use a puller.

Re: Stupid TFR Kinetic (Electrical Problems)

Andrew Da Silva /

Gah. I believe my kinetic is having the same problem. I thought it was something I did... (still might be) but all of these symptoms seem the same. and I've only had mine since valentines day.

Re: Stupid TFR Kinetic (Electrical Problems)

you guys are lucky to have such intellegent and concerned people working for you for free. relax a little.

i wouldnt try to tackle this one my self, completely.

as far as trying to use a voltmeter, don't try. use the grounded spark plug method. look for a blue spark. it did sound like a bad coil somehow at first. i would replace that first. like how much can an new coil cost?

Re: Stupid TFR Kinetic (Electrical Problems)

Jake have you try hot wiring around the ignition switch. You should have a black wire and two whites.(I think one of the white wires comes from the kill switch on the right handle bar.

try wiring the the other white wire and black wire together and see if you can get spark thru the plug. You can also use your voltmeter to see if you are getting juice thru the White (hot) wire when you pedal. That white hot wire traces all the way back to the magneto coil.

1080381154_tfr_web_wiring.jpeg

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

interesting....

I'll try this by the end of the week.

Thanks for sticking with it!

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

If you have any luck with this, please, please, PLEASE let me know!

thanks.

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

Lala,

Any resolution to this?

We took off the magneto to find nothing out of the ordinary. This is quite frustrating. Cosmo will not call us back, either.

--jake

Re: Stupid TFR Kinetic (Electrical Problems)

Looking at the diagram, it's not complicated.

The magneto has two windings (and a permanent magnet not shown). The yellow/black pair drives the accessories and the white/red pair drives the ignition. They appear to be electrically equivalent, though their values in turn count are not shown, so that may not be the case. Each has a connector you can separate for testing.

Pull the connector, attach a resistor across so the winding isn't totally open circuit, and attach an analog voltmeter across the leads. Choose the highest voltage range first, then step down until you see the needle move, though I expect the 15-20V range will end up being the one you want. Pedal to spin the engine and see if there's voltage appearing across the first winding, then switch to the other and perform the same check. If they're both alive, I doubt there's anything at all wrong with the magneto. Conceivably some windings could be shorted and still let the magneto perform with degradation, but it's very unlikely.

(Your post didn't say if you had tested both coils of the magneto, nor if they appear equal.)

(Ideally you could use a scope to see the pulse from the CDI unit to the coil primary. Knowing there's something coming across the primary as you said suggests the CDI unit is likely okay.)

If both halves of the magneto seem okay, then it's 1) wiring 2) CDI unit 3) coil.

Take the coil out of circuit, put a resistor across that lead to ground, measure across with an analog voltmeter. If it pops as you spin the motor, there's a pulse to the coil primary. If not, the CDI unit is bad.

(You did say there was something coming from the CDI output. I'd prefer to see the pulse on a scope, but we make do with the tools at hand, so "something" is probably the best we have to work from.)

If there's a pulse to the primary but insufficient voltage at the secondary (do not try to measure that with a voltmeter, it's too hot), then figure it's the coil. Try replacing the coil. If that fails, then go through the wiring diagram step by step looking for a short to ground or open somewhere. Undoing all the lights first may simplify your task.

It's just a matter of eliminating possibilities step by step, and with a wiring diagram in hand, the major source of mystery is removed.

(From what you said in your post, it sounds like the coil may have some windings of the secondary shorted. I'd try replacing that first, if you can't lay hands on better electronic test gear than a voltmeter.) And always insert a resistor in circuit before you take voltage readings. Open circuit readings tend to be deceptive.

Good luck.

PS The ignition kill switch works by shorting the white wire to ground, either the black ground wire, or chassis ground. The white wire runs to the CDI unit and back to the magneto ignition-side winding. Shorting that to ground starves the CDI of power to pulse the coil. In effect, it shorts the magneto ignition-side coil. Simply disconnecting the white wire from the ignition switch completely should remove any possibility that's the culprit. But I doubt it as you report something happening across the coil primary. So the coil remains my #1 suspect. If there were a short from the coil secondary to ground lug, that would produce the symptoms you describe: something on coil secondary when its ground lug is disconnected/floating and nothing when the lug is tied to ground.

Re: Stupid TFR Kinetic (Electrical Problems)

Jake Van Order /

thank you very much. I'll try this tomorrow and hopefully, this will work. we'll see!

--jake

The Winner is....

Jake Van Order /

...Dnyberg! He guess the coil and he was correct!

We replaced the ignition coil and now it sparks. We couldn't believe it but it does. In fact, I rode it around for awhile just to make sure it doesn't break anytime soon. Thank you everybody for your help.

--jake

Re: The Winner is....

Bravo Dnyberg.

Re: The Winner is....

That was a great post. M. A. should save this one for future reference.

Re: The Winner is....

Congratulations Jake on getting it running.

I wouldn't say Dnyberg "Guessed" it was the coil. He was thorough in his analysis and trouble shooting from the wiring diagram and through the component by compenent process of elimination pinning it down as the probable cause, the coil.

Superb job of remote trouble shooting by dnyberg.

So congratulations to both Jake and Dnyberg

Happy Trails

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