Setting timing on a 1981 YZ125 using a dual guage.

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11/4/2017 8:25 AM

I'm having trouble setting the timing using a Motion Pro dial gauge following a restoration. After finding TDC, then moving to the appropriate mm advancement, the mark on the fly wheel is at about 7:00 o'clock and I can't rotate the stator plate far enough to bring those two marks together. Any help would be appreciated!


11/4/2017 11:14 AM

Be sure the stator coils are not mounted backwards. I bought an 82 YZ125 that was rebuilt by the previous owner and he couldn't make it run. I found that the stator coils were backwards and it was firing 180 deg. off. You can check the timing without the engine running by removing the spark plug, hooking up the timing light and spinning the engine with a drill from the flywheel.


11/4/2017 11:27 AM

Thanks, I'll check into that!


11/5/2017 2:21 PM

Don't forget that the spark plug still needs to be grounded to make it arc.


11/5/2017 3:39 PM

OK, thank you!


11/5/2017 4:15 PM

Also, pull the flywheel and make sure the woodruff key is not sheared.

It could be that the flywheel is not oriented correctly on the crankshaft and has spun. If that's the case you'll never get it right.


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2013 KTM450 Factory Edition
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