kdx 175 1981 , no spark

[AJWASHERE]

hi guys , i just bought a kdx 175 1981 (the deal was a steal)
but now im not so sure , i get no spark , ive now been told that i need a battery , (not so sure bout that ) ive replaced the spark plug , spark plug cable , and with very little knowledge am quite sure its earthed ! i get a reading with my multi meter from the magneto , ive replaced the starter coil but with no luck ! should i replace the cdi ? are there guide lines as to what my magneto reading should b ? the bike was running (then striped down and had the frame painted) then i bought it ! i was told it must b a earthing problem , but after days off fidling im pretty sure its earthed !

Im pulling my hair out here ! just want to hear her start up !!!!! any sugestions ?

thanx aj. :rotfl:

 

[glad2ride]

Do you know if it ever ran recently? Was it running when they took it apart? If so, how long ago?

Thanks for the language funny. In the USA, we call it grounded instead of earthed. That is cool.

 

[AJWASHERE]

lol ! im here in sunny south africa ! It was running before they sprayed the frame ! id guess it stood for maybe a month or two , the magneto puts out 6.4 v ? is that enough ?

 

[_JOE_]

You really need to find someone with a manual or a running bike just like yours and a multi-meter. Did you make sure all the "earth" points had all the paint cleaned off?

 

[sr5bidder]

Also be certain that the kill switch and wires going to it from the cdi are not grounded. If you have a spot for a battery try putting a ni-cad or other avalible 6-7.2v source on it, I use radio controled car batteries in my wifes old 73 xl175 as it wont run (spark) without a battery.

 

[glad2ride]

Yes, make sure that the coil mounts to a bare frame. That might be an issue.

 

[digifox]

Also be certain that the kill switch and wires going to it from the cdi are not grounded.

Ditto

Also be sure your CDI is wired up right.
And battery, My moms Triumph wont start if the battery is disconnected.

 

[dirt bike dave]

FWIW, stator failure is common on the old KDXs. You still can get a spark, but just not strong enough.

It's hard to diagnose, and the problem can be intermittant at first (first, the bike gets hard to start cold, then it will cut out when hot and not restart until it cools down, then eventually it just will not start or run at all). Since you are a new owner, you don't know if the problem came about gradually over time.

You may want to replace or rewind the stator. There are some measurements you can take with an ohmeter, but when mine failed, it still measured within spec.

You will have to remove the flywheel to get to the stator.

 

[Hoffies]

Not to familiar with your setup, but you must remember that there are usally lighting coils/windings(normally around 6v to regulator for lights) and exciter windings/pickup windings for your CDI(spark) Are you measuring the correct outputs? It is also difficult if you are measuring outputs with digital multimeter whilst kicking over bike(sample rate of meter too slow, non true readings)It is better to use analogue meter. I agree , make sure metal plates on coil are grounded and stop wire(kill wire) not grounded(faulty stop switch etc)