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Discussion Starter · #1 ·
No spark help

I'm stuck on finding my problem..

On a 86 trx125 I'm getting no spark.. I'm 99.9% sure it's not the CDI. I've checked it with 2..

OHMed everything out and here's what I've got.


Manual says

Primary coil: 0.18+or-0.2 I'm getting .3

Secondary coil: 4.1+or-0.4 kohms I'm getting 4.348

Exciter coil: 100-400 ohms. I'm getting 303.9


Pulse generator: 90 ohms. I'm getting 93.5

What am I missing??


Stator ohms good





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pull the spark plug boot off, lay just the wire on the engine, crank it over, get spark then ?. I know some Hondas use a resister in the spark plug boot.
 
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Hi: Also do you have a Neutral light -- do the lights work? If so unplug the Bl/W on the Ign. switch and try starting the bike.
 

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Did you unplug the Bl/W wire? -- if so place a jumper wire in along side of the green wire on the Ign. coil and the other end of the jumper on neg. of battery -- try starting.
 

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Discussion Starter · #7 ·
Did you unplug the Bl/W wire? -- if so place a jumper wire in along side of the green wire on the Ign. coil and the other end of the jumper on neg. of battery -- try starting.


Didn't have a chance today.. I'll look at it tomorrow.. 16 hr day and I'm pooped..


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Will this work? Its a resistor cap, if needed. The non resistor cap is right next to it on the Dr ATV site. Short money either way though he is a little high on shopping.

RESISTOR SPARK PLUG CAP 1/16W (23D)

Rick
 
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Who's got one for sale??


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can you unscrew the cap out of the boot where the spark plug goes in ?. if it has what looks like a standard screw driver slot inside the boot ?, unscrew it, check the resister under the cap :).
 

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or, trim about 1/4 off the coil wire, then screw the boot back on, then check for spark again with the spark plug in boot, laying on engine.
 

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I got it to fire with one off a 300.. Is the resistor just for noise??


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sorta, it's suppose to stop interference to electrical equipment, stupid..right ?..lol.
 

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Discussion Starter · #16 ·
or, trim about 1/4 off the coil wire, then screw the boot back on, then check for spark again with the spark plug in boot, laying on engine.


Already did that.. nothing

I'll look for the screwdriver slot. I OHMed it out. One time I got around 24 ohms. I didn't see anything in the manual about reading resistance on it...so... not sure what I was looking for..




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Hi: Are you using a DR8ES spark plug? -- the R on the plug stands for resister plug.
 

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My guess for a Honda resistor plug cap would be 5000 ohms. Yours sounds like a non resistor cap. They tend to increase in resistance with age if it is a resistor cap. I had to replace all four on my 72 Honda CB500 because they ranged from 5300 ohms all the way up to around 12,000 ohms which drove that bike's ignition system crazy. Much mo' betta' now.

Rick
 
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Discussion Starter · #20 ·
My guess for a Honda resistor plug cap would be 5000 ohms. Yours sounds like a non resistor cap. They tend to increase in resistance with age if it is a resistor cap. I had to replace all four on my 72 Honda CB500 because they ranged from 5300 ohms all the way up to around 12,000 ohms which drove that bike's ignition system crazy. Much mo' betta' now.



Rick

Interesting, I've never learned so much about plug caps till this week.. Always good to know.

I got another one off an 86 125.. Probably won't get to mess with it till this weekend.. LONG week at work.. Generator exhaust caught on fire, fire alarm computer crashed, contractor shorted out emergency circuit and tripped switch gear breaker, tablets crashed and can't log work orders. And I still have one more day to go...



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