ATC-110 No Spark, stumped!

[XL-erate]

Thoroughly stumped! No spark on a Honda ATC-100. No-loss no battery ignition.

Tested then eliminated kill switch. Running direct out of alternator black wire direct to points wire, tee'd to coil + on primary. Points adjusted, tested for ground, cleaned, wire tested for continuity, no shorts or incorrect ground. Points cover cap not shorting out points wire. Points insulator at wire connection correct. Points test correctly, open for most of crank rev, close to ground at correct time.

3 different coils tested and tried, one's a brand new universal 6V/12V coil. Tested from coil + black wire coming from stator to ground, meter shows continuity just like a stator test.

Various sparkplug wires and end caps, several testing correctly. Sparkplug tests good continuity from connection tip through electrode.

Tried 2 different stators, both pass all tests, one higer resistance to ground than the other. Stator to rotor clearance checked, rotor has good strong magnets. One stator had rubbed on rotor in the past. Best stator's continuity show 4 ohms to ground on black lead. Other stator falls to 2 ohms to ground.

Eliminated all extra wiring and running direct, ignition only. Coil properly grounded, engine & chassis grounded. Checked all wiring for shorts etc. Condenser taken out of circuit, but no different with it in circuit. All wiring connections are clean and tight. Fresh rebuild & semi-resto, everything nice and clean.

No spark. ----> ???

[Nick_R_23]

Looks like you pretty much covered everything, only other thing I would look at is the flywheel, are the magnets cracked/missing, sheared keyway, or is it even the right one?? Other then that I cant think of any other causes....

-Nick :TrikesOwn

[redryder]

Had an ol Harley Biker tell me that if all else fails working on bikes with points replace the points. Had the same problem on my 110 it worked.

[TeamGeek6]

"3 different coils tested and tried, one's a brand new universal 6V/12V coil. Tested from coil + black wire coming from stator to ground, meter shows continuity just like a stator test.'

HUH? Cant do that, thats not a battery ignition. Its basically a CDi (just without the capacitor). The stators ignition winding makes high voltage (100-300 V AC) which the point keeps shorted out till the crank is at firing time, then the point opens and whacks the ignition coil with stator voltage.

Most motorcycle failures are bad wiring connectors, especially in old cycles. Thats the thing to go to when youve replaced all the parts 3 times and it still wont run.

Disconnect the black wire from the ignition (stator) and hold it and ground wire between fingers and kick it over, see if it shocks you a little.

"3 different coils tested and tried, one's a brand new universal 6V/12V coil. Tested from coil + black wire coming from stator to ground, meter shows continuity just like a stator test."

Resistance tests mean nothing, ignore them. These are coils and they have "inductance" and the inductance value is what determines whether the coil is good, not resistance (unless the coil is completely open, which it usually isnt).

[Vealmonkey]

According to the Honda manual this is what to check for on little or no spark:
Faulty Spark Plug, Fouled Spark Plug, Faulty CDI Unit, Broken of Shorted High Tension Wire, Faulty Alternator, Broken or Shorted Ignition Coil, Faulty Pulse Generator, Poorly Connected, Broken or Shorted Wires, Pulse Generator Rotor Air Gap Incorrect.
The manual lists the ohms between the blue, yellow and green wires in the pulse generator should be 90 ohms. The air gap of the pulse generator should be between .30 and .40 mm.
The manual says if you don't test the cdi unit with the correct tool it will give you a false reading. I have other specifics listed in the manual if you are interested. Hope this helps.

[XL-erate]

Thanks a bunch, folks!

Let's see: stator rotor/flywheel: looks okay, all magnets in place and strong, slightly scarred exterior under stator coils. Checked clerance all around at all poles.

Brand new points, plus I cleaned them and tested them. Used meter between points wire & ground. No continuity until points close, then good continuity to ground.

Tried 3 different coils, no change. That coil test procedure was in Honda manual for these coils, don't know otherwise. On this bike the points remain open while coil charges, then they close to ground. As I understand it that collapses the field and causes spark at plug. Points are open for about 3/4 of rotor rotation, closed for about 1/4. Unfortunately I don't have an inductance tester for coils.

Been through the wiring and tested all circuits, all okay. Connectors cleaned and tight.

This is a 1980 non-CDI scooter but thanks for posting values.

Well, then it sounds like a bad alternator/stator, can't imagine what else????
Haven't tried holding on to stator wire while pulling it over....

[Vealmonkey]

You didn't say wether or not you have a new plug or plug correctly gapped. And as for me giving you the cdi stats, you stated above that you had a no battery cdi system. And your points should be closed for about 3\4 of the rotation and only open of less than 1\4 of the rotation. Check your points plate closely, make sure you are not grounding anywhere and that your screw for your points setting isn't loose and letting the points close. I guess your condenser is ok. I would try new points condenser and plug. Do you have a wiring diagram to make sure your wires are correctly hooked up? You should have all the wires colormatched. Make sure you don't have a dead short in your headlight, I've seen that affect the trikes starting and running. If you have the headlight and taillight hooked up, unhook them and make sure the connections are covered and not touching any metal and try that. Also try bypassing the starter switch by just unhooking the switch and hooking the wires together without the switch.

[TeamGeek6]

"Been through the wiring and tested all circuits, all okay. Connectors cleaned and tight."

There is no such thing as cleaning connectors. Once the halves of the terminals get corroded and worn from vibration, thats it.

[XL-erate]

Thanks for all the helpful feedback, guys!

This is an '80 ATC-110 that has no battery and no starter, just pull cord, and no CDI. The bike is wired according to the diagrams given in the tech stickies in this forum for '79-'80 ATC. I've tried other wiring combinations also. Lights wiring isn't hooked up, I just have the yellow wire disconnected.

It looks like the design of this ignition has points open for most of the revolution then closing to make the spark. I was thinking points should be closed most of revolution, then opening to collapse field and generate spark but that's not possible the way this thing is set up. I'll double check that when the sun comes up.

I thoroughly checked the points plate, it grounds to the cylinder head. Checked wire connector and it's well insulated and wire doesn't touch point cover.

On cleaning connectors I'm talking about the spade terminals which become corroded, those I cleaned. I checked all wires for continuity and all tests okay.

Just may be the points aren't the right ones or something, being closed when they should be open and vice-versa. I'll double check that this morning. I've worked on small engines for many years but not much on cycles with this ignition system. Thanks a bunch for the help so far, good info!

[Hair Bear Bunch]

I would suggest taking a plug from another mchine that works, doesn't matter wether it fits or not as long as it's a working machine, hook up to the plug lead and spin over see if that sparks. I've had plugs with a dead short in them which gives a good reading tip-to-core, but the same reading tip-to-base!

[XL-erate]

Well, posted a reply with pic and it was breakfast for the cyber monsters! I'll try again: couldn't wait for sunshine so went out in the dark and chipped the ice off, how's that for obssessed?

Checked points: closed for barely 90* or rotation, open for the rest, exact opposite of correct setup! Maybe prior owner or another installed the wrong points. They're new and there's not but one poorly stocked cyce shop anywhere around: "Try these, they'll probably work...."

Thanks Redryder, TeamGeek6 and Vealmonkey for re-convincing me that points should be CLOSED for entire revolution except to fire at TDC! Thanks to everyone else for excellent tips!

I'l try the pic again, of points setup before rebuild, re-installed same after rebuild; they were new points so I left them in. May be the right points, wrong points cam too.....

[XL-erate]

By the way, I've got a mid-70's Honda Trail 90, looks pretty much the same engine except kick start and uses a battery, which ATC-110 doesn't use. Any chance the points & points cam would swap over? Seems they'd be the same but I know how Honda likes to fiddle around swapping parts. Thanks!

[Vealmonkey]

yes, it all should swap out, heck even the engine will swap out but you would have to change over the front mount on top of the head from the 90 to the 110 and you could change the 110 to the pull start if you wanted. And if you want a cheap performance upgrade, swap the ct110 cam and carb to the 90, but you would be better off finding a atc110 intake. The ct110 carb is larger and the ct110 cam has a better profile than the atc90. I'm not sure if the ct110 cam profile and the atc110 cam profile are the same, I thought they were different.

[XL-erate]

Thanks, maybe I'll have what I need to get the points working right!

[XL-erate]

2 things, one important, one dark, ugly and wicked.

One: the 1980 ATC-110 points cam is designed so that points are closed only for a very small part of crankshaft revolution, like maybe 90* if that long? I checked my 70'2 CT90 Honda Trail 90 motorcycle and it's exactly the same, designed that way. Points are open for at least 250* maybe 270*+, then they close for about 1/4 or less of crank revolution. I assume ATC-90 is the same. No idea why it's designed that way, seems real strange to me. There's a flat ground into cam on one side, just enough to occassionally close points, that's it.

Two: the dark, ugly wicked part is that my stator is toast and no way can I afford one! Hooked up an analog meter, with needle display, and the needle hardly flickers when set to 10V AC. That ain't enough to lite a firefly's butt so I'm dead in the wawa for a long time. Oh well, thanks for the help all!

XL-erate

[XL-erate]

Well, got some sunshine on that dark ugly wickedness. Remembered that on a lot of small engines like Tecumseh, Briggs, & chainsaws it often helped to clean up the magneto. So, I pulled the alternator rotor and polished the heck out of it with a small wire brush, and polished the stator end pieces that ride right outside rotor. Vacuumed it all and pulled all the junk out.

Yanked it over with the analog voltmeter in ciruit and it pegged the needle! Switched to 50 volts range and it's hitting near 20 volts!

Tried to hook up my now confusing wiring and still don't have spark but the list of possible problems just got smaller, and cheaper! Only thing left is rewiring with a known good coil, plug wire and end cap. Could be this 'Universal 6V-12V ATC colt' I bought will work, but doubtful. Anyway, a lot closer!

[Vealmonkey]

Are you watching the points being open without the flywheel in place? I believe if you look, the points are actually set to run on the center of the flywheel, not the shaft the flywheel attaches to. I've got to go down and look at one now with the flywheel on and off.

[XL-erate]

I'm a little confused what you mean. The points are on the points plate attached to cylinder head at end of camshaft. Points actuating cam is attached to end of camshaft by a bolt. Chain drives cam from crank case.

'Flywheel' is actually the stator rotor, the hub section with magnets, running inside stator and that inside crankcase cover.

Observing rotation of flywheel hub, where timing marks are located, the points cam only closes points for about 1/4 of one full rotation of crank, or about 90* or less. This is on an '80 Honda ATC-110. I checked my Honda Trail 90 motorcycle, similar horizontal single cylinder, and points cam & function is identical, points only closed for about 90*.

Sure seems strange to me, and contrary to any other engine I've worked on!

[Vealmonkey]

You're right, I was thinking of the yamaha gt80 I timed the other day, duh. Been working on too much different stuff lately. Too early in the morning. I have the manual for the earlier trikes too if you need any info. I was just sitting here thinking that I wasn't making any sense and referred to the shop manual. Thank goodness for shop manuals.

[XL-erate]

Yeah, happens to me all the time, working on gas & diesel trucks, motorcycles, 3 wheelers, chainsaws, small engines: where was I, where am I?

Thanks for the offer on the manual! I may need some info soon, as my only 'manual' is an internet download. One thing that my wiring diagrams don't clearly show is what the proper connection to condenser is.

Looks like the ignition hot, stator black wire goes to points & to coil primary [and kill switch] and also tee's and connects to condenser green wire? If you get a chance some time I'd appreciate that info. Thanks!

XL-erate

[Vealmonkey]

What you're saying about the wiring t-ing is right. Not sure how to scan the picture to show you how the manual shows it. The Green wire from the points goes into the T at the condenser. There should be a black wire at you coil that connects to the same T at the condenser. Then also that black wire should have another wire that goes into another connector which should hook into a T coming of the magneto. The other black lead that hooks in the T from the magneto should hook into your headlight switch. Hope that makes sense. Also since you seem to be way more electrically savvy than I do, and probably way more familiar with the electrical flow, the "coming out of" and "going to" that I'm using are not proper electrical flow patterns, I'm just looking at the diagram.

[Vealmonkey]

Hopefully this helps.

[XL-erate]

Thanks, buddy, big help! That explains it much better than what I had for schematics.

I think I'll cut to the chase and just yank the whole wire loom and scratch build with soldered connection, heat shrink and Scotch 33+ tape. May throw in a connector here & there to pull parts, but everything else soldered new wire. That removes a lot of doubt. Thanks again!

[cajunchilipeper]

I was having a similar problem....I sprayed wd-40 on all electrical components....and I also cleaned all the grounds and she started right up. Make sure that the cdi isnt red on the inside. Mine was.......hope u get her runnin...
Thoroughly stumped! No spark on a Honda ATC-100. No-loss no battery ignition.

Tested then eliminated kill switch. Running direct out of alternator black wire direct to points wire, tee'd to coil + on primary. Points adjusted, tested for ground, cleaned, wire tested for continuity, no shorts or incorrect ground. Points cover cap not shorting out points wire. Points insulator at wire connection correct. Points test correctly, open for most of crank rev, close to ground at correct time.

3 different coils tested and tried, one's a brand new universal 6V/12V coil. Tested from coil + black wire coming from stator to ground, meter shows continuity just like a stator test.

Various sparkplug wires and end caps, several testing correctly. Sparkplug tests good continuity from connection tip through electrode.

Tried 2 different stators, both pass all tests, one higer resistance to ground than the other. Stator to rotor clearance checked, rotor has good strong magnets. One stator had rubbed on rotor in the past. Best stator's continuity show 4 ohms to ground on black lead. Other stator falls to 2 ohms to ground.

Eliminated all extra wiring and running direct, ignition only. Coil properly grounded, engine & chassis grounded. Checked all wiring for shorts etc. Condenser taken out of circuit, but no different with it in circuit. All wiring connections are clean and tight. Fresh rebuild & semi-resto, everything nice and clean.

No spark. ----> ???

[TeamGeek6]

Yanked it over with the analog voltmeter in ciruit and it pegged the needle! Switched to 50 volts range and it's hitting near 20 volts!

. Could be this 'Universal 6V-12V ATC colt' I bought will work, but doubtful. Anyway, a lot closer!

Voltmeter reading is absolutely meanignless, the AC pulse shoudl be 150-300 VAC. Go on and blow the meter sky high and youll have something else to fix!..

One more time. You CANNOT use a 12 volt coil on that system.

Reading is fundamental!

[XL-erate]

I agree that reading is fundamental: try reading my post again with both eyes open? You'll see that it is not a 12V, but a combo coil, 'Universal 6V/12V Coil' designed to work with either voltage. Yes, there is such a thing.

What make and model of meter do I have? I figure you'd know being as you seem to know its limits? Regardless, I am getting a good solid reading which I wasn't before so I'm satisfied, and the meter is just fine, thanks.

Also I would disagree that voltmeter reading is absolutely meaningless when it has demonstrated that I now have roughly 40-50 times the voltage I had before cleaning corrosion from parts.

I've been an electrician since 1977, just have no experience with this system.

[Vealmonkey]

I knew you had a strong electrical backgrouind at least.

[XL-erate]

Yes, I've been a mechanic and electrician for a very long time. Within that I've been continuously amazed, throughout the years and presently, "Huh, I'll be darned: I didn't know that!?" Nothing with as wide a learning curve as these infernal machines!

Thanks to all for the help, and if it isn't blowing cold too hard outside may tinker some more today, and will keep y'all informed of new discoveries!