[TRX84]

I have an 84 TRX200 that wont start because the plug wont spark. I've checked all the wiring which is good and verified the kill switch is operating correctly. The bike turns over with the electric starter just fine, it just wont run. I've replaced the plug, and the plug cap which was bad due to high resistance, but didn't fix the problem.
I'm hoping someone can help me who is familiar with expected voltage readings. I have a service manual but it only provides expected resistance reading information, not voltage readings. Here's what I know. When I run the starter, the AC generator is producing about 45 volts a/c input to the CDI (I suspect this is good), and the pulse generator is producing about 6.5-7.2 millivolts input to the CDI (unsure if this is a good reading). The resistance checks for both of these agree with the service manual. The voltage output from the CDI to the input of the coil is about 12 volts when running the starter (I suspect this is not good). The resistance check for the coil agrees with the service manual as well. I suspect the problem to be either the pulse generator or the CDI.

Please advise- Thank you

 

[shadetree]

I have an 84 TRX200 that wont start because the plug wont spark. I've checked all the wiring which is good and verified the kill switch is operating correctly. The bike turns over with the electric starter just fine, it just wont run. I've replaced the plug, and the plug cap which was bad due to high resistance, but didn't fix the problem.
I'm hoping someone can help me who is familiar with expected voltage readings. I have a service manual but it only provides expected resistance reading information, not voltage readings. Here's what I know. When I run the starter, the AC generator is producing about 45 volts a/c input to the CDI (I suspect this is good), and the pulse generator is producing about 6.5-7.2 millivolts input to the CDI (unsure if this is a good reading). The resistance checks for both of these agree with the service manual. The voltage output from the CDI to the input of the coil is about 12 volts when running the starter (I suspect this is not good). The resistance check for the coil agrees with the service manual as well. I suspect the problem to be either the pulse generator or the CDI.

Please advise- Thank you

your c.d.i or stator could be bad..the stator has two power sides to it..one charges the battery/lights..the other sends power to the c.d.i..then to coil..then to spark plug..change out your c.d.i..before you replace the stator...make sure you use the same year and make with the c.d.i. check the ground on the coil..you may not have a good ground ?..remove the spark plug cap < unscrew it >.with the wire end if it..crank the bike..< make sure you hold the wire to the engine >...do you get fire then ?..if so..your spark plug cap is bad..if not..then your problem lies with either the stator..c.d.i..or pick up coil < pulse generator >..it could be anyone of these..its all about eliminatiion here.

 

[TRX84]

Thanks for the reply- Based on what you've said I suspect the CDI. My charging system is working fine and I get 12v input to the CDI on the gray wire. The ground on the coil is good and I get no spark from the wire with the plug cap removed, as you described.

Do you know what voltage level I should see on the coil leads (directly fed from the CDI). With 45v coming from the stator I expect to see more than 12v out of the CDI for the coil.

Thanks

 

[dr. feelgood]

Your kill switch isn't set to off is it? Don't laugh I fought with a Big Red 250 trike for a while trying to get spark and finally looked at the kill switch set to off lol.

Rob

 

[Helmut]

If you checked the resistance of the stator, pulse generator, and ignition coil primary and secondary windings and they were within specs according to the manual, then I would replace the CDI.

I believe the '84 TRX200 had the pulse generator on the side of the head in front of the cam sprocket. Before you replace the CDI, make sure the pulse rotor and pulse generator air gap is set right. If it isn't set right, it will not fire.

 

[TRX84]

Thanks helmut for the help. I will check the pulse generator first- i suspect something is wrong there only getting 7 millivolts a/c output there. Thanks

 

[Helmut]

Thanks helmut for the help. I will check the pulse generator first- i suspect something is wrong there only getting 7 millivolts a/c output there. Thanks

The pulse generator should be easy to check by measuring the resistance across it. All a pulse generator is, is a hall effect sensor which is nothing more than a coil of wire. If it measure's within specs., check the air gap at the pulse generator and rotor.

 

[TRX84]

Still having troubles....I checked the pulse generator and it seemed good (gap and resistance). So i replaced the CDI and i'm still not getting any spark- i thought for sure that was the problem.
Back to the drawing board. Still wondering what voltage readings should be. My readings I get are:
Pulse Generator: 7 millivolts
AC Generator: 40 vac
CDI output to coil 12volts

My ride red shop manual says the alternator output is 4.5A/5000rpm (at 14V). I'm wondering if the 40V is too high, or is that supposed to be the regulated output for the charging system?

Any insight is appreciated. Thanks

 

[Helmut]

My ride red shop manual says the alternator output is 4.5A/5000rpm (at 14V).

That would be the regulated voltage at the battery. I don't know how many volts the generator is supposed to put out. Don't the manual have a resistance test for the components?

 

[TRX84]

Yes the resistance values are in the manual and the measurements check out good. Pulse gen: spec 30 +/- 10 ohms, actual is 29 ohms, and the AC generator spec is 100-400 ohms and actual is 298 ohms.

I just did another resistance check on the coil; the spec on the secondary coil is 4.1 +/- .4k ohms and it actually measured at about 8kohms- perhaps thats it???

 

[Helmut]

I just did another resistance check on the coil; the spec on the secondary coil is 4.1 +/- .4k ohms and it actually measured at about 8kohms- perhaps thats it???

Could be it, it's got to be something.

 

[Honda_crf230]

i have the same bike, tough old bikes. mines an 84 with 6750klms on it MINT. i have an old 84 honda 200s that i was having spark problems with too. i changed the spark plugg, coil, cdi and ignition controll but nothing still. so the only thing was the stator coil. i check on google and thay say its the part that goes bad 99% of them time on them old Hondas. its cheap to replace but hard to find part. it cost me 25$ CDN to replace and it was the problem. started first pull. check at Auto parts extra, thats where i got mine. hope this helped

 

[Gravelyguy]

Hope I can look for answers too.

Same '84 trx200 with no spark. I'm just getting into this.
I bought it used a few weeks ago and it ran fine up until today.
My daughter rode it yesterday parked it, and today nothing.
I've been reading lots of threads on this at a few sites.
I've still got to tear it apart but here's what I have....

Primary coil is fine.
NO resistance through secondary coil. Either through the cap or just the wire.
As a matter of fact, I get no reading through the cap itself at all. Wierd?

Pulse generator seems fine although the gap is a little big.
When cranking with starter, I get a reaction with a meter between the two coil wires.
blk/ylw & grn.
I tried with both ohms and volts. Values were fluctuating during cranking time.
Doesn't this mean the pulse generator and/or stator is working?

Also, ever since I've had it, the neutral light never stayed on consistently.
It would flicker at low idle mostly, sometimes with engine off but key on it would work too.
Right now since no spark the neutral light won't come on at all.
I haven't pulled the ignition switch off yet to test,
but reverse lights up, headlight works, and above results seem to indicate the key switch is OK?
But the neutral switch is faulty?? Would this affect spark?

Since I have signal at the coil wires, is this before or after the CDI?
If after, wouldn't the CDI be working?
I'm thinking the coil is bad, but wondering what killed it?

 

[shadetree]

Hope I can look for answers too.

Same '84 trx200 with no spark. I'm just getting into this.
I bought it used a few weeks ago and it ran fine up until today.
My daughter rode it yesterday parked it, and today nothing.
I've been reading lots of threads on this at a few sites.
I've still got to tear it apart but here's what I have....

Primary coil is fine.
NO resistance through secondary coil. Either through the cap or just the wire.
As a matter of fact, I get no reading through the cap itself at all. Wierd?

Pulse generator seems fine although the gap is a little big.
When cranking with starter, I get a reaction with a meter between the two coil wires.
blk/ylw & grn.
I tried with both ohms and volts. Values were fluctuating during cranking time.
Doesn't this mean the pulse generator and/or stator is working?

Also, ever since I've had it, the neutral light never stayed on consistently.
It would flicker at low idle mostly, sometimes with engine off but key on it would work too.
Right now since no spark the neutral light won't come on at all.
I haven't pulled the ignition switch off yet to test,
but reverse lights up, headlight works, and above results seem to indicate the key switch is OK?
But the neutral switch is faulty?? Would this affect spark?

Since I have signal at the coil wires, is this before or after the CDI?
If after, wouldn't the CDI be working?
I'm thinking the coil is bad, but wondering what killed it?

try taking the spark plug boot off the coil wire..crank the bike with the coil wire nearly touching the engine cylinder...does it spark ?..if so..your spark plug boot is bad...also..if i remember on some of those older models..honda used a spark plug coil that had a inline slow blow fuse just inside the end of the spark plug boot..when you unscrew the boot off..there might be a fuse there ??..and blown..if so..either replace it..or just do away with it...as for your neutral light twitching at idle..this is a inditcation of a bad stator..as it's not charging or a low output.

 

[Gravelyguy]

Thanks Shadetree.

There is no continuity going through the cap so it's bad for sure.
You mentioned it is not needed to be factory? I can just put a standard terminal on?

I did have spark without the cap. At first I had one spark when cranking.
Then I wiggled the coil leads around and eventually got it jump to the plug about 1/8"
fairly consistent. I say fairly because the spark doesn't start until the engine turns 1 or 2 times.
Then it seems constant. It's not a real snappy blue spark, but it is there.

However it still won't start. I think the plug is crappy too, so I'm hoping that is it.
As for the stator, I haven't noticed the battery going dead.
Thinking about it, when I started it cold I would turn it over for a few seconds with the starter/choke, but it wouldn't fire until I pull started it. I just thought the starter turned too slow.
Once warm, it would start right away with either method.

I'll put a standard plug end on and a new spark plug and cross my fingers. Thanks for the help.

 

[Helmut]

There is no continuity going through the cap so it's bad for sure.
You mentioned it is not needed to be factory? I can just put a standard terminal on?

You can use a sparkplug boot from about any ATV, doesn't really matter what brand it is. I have used Honda sparkplug boots on Yamahas and Yamaha sparkplug boots on Hondas.

 

[Gravelyguy]

Sorry it's been so long.
Got new boot and clipped the wire shorter, new plug.
Re-gaped the pulse generator and it started right up.
A little noisy, but adjusted cam chain and it quieted down.

New carb kit and it runs awesome.
Really can't believe how well. It will idle all day and no lag off the line
Neutral light flicker was simply a bad bulb, go figure.
Thanks guys.

 

[Helmut]

Glad you got it fixed!!