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View Full Version : Timing question....rare occurrence I would say



Manns50
10-17-2011, 08:02 AM
Have an 81 200 was riding was running good when I felt the motor start dying and I heard a low rattling sound. When I tried to restart the rope would snap back on every 3rd or 4th pull and I could hear a Popping sound out of the exhaust at random pulls as well like it was out of time. Got it back to the Garage short on time I pulled the round cdi cover off to see if the timing chain had broke if the crank Pickup magnet (whatever it's called) was still turning. Well it was still turning but I noticed one of the screws that was holding the pickup down had came out and was stuck to the magnet causing interference with the magnet and pickup. Removed the screw and washer and turned it over but was still acting like it was out of time. My question is could it jump time under these conditions? Sure the chain is not broke since that is still turning but the magnet seemed tight as well unless it just moved when the screw jammed.

dougspcs
10-17-2011, 08:12 AM
That is an adjusting screw to hold the plate..ordinarily you would loosen the screw then adjust the base timing with a timing light by moving the plate back or forth.

Yours obviously shifted when the screw popped out..look closely at the plate and see if you can spot the wear rings left by the screw when it was seated. Move the plate to that position and tighten then retry..

If this doesn't fix then the A/C generator or spark advance mechanism may have gotten damaged by the screw tumbling around..you'll need to find replacements.

Your timing chain won't have jumped because of this, unless your engine was fuked in the 1st place.

Manns50
10-17-2011, 10:57 AM
Ok thanks for the input I will check that clearance of the pickup and set it to the original specs. Will look up how to time it and make sure it's in time....my question is will the magnet that spins....will it rotate on that shaft or is it splinned? So the little black box that the screw backed out of (pickup)....that adjustment is for timing advance only?

oscarmayer
10-17-2011, 11:15 AM
in my sig is a link to repair manuals. download it and read it. it will telly ou how to do it per the factory specs.

it's a pdf

dougspcs
10-17-2011, 11:38 AM
Ok thanks for the input I will check that clearance of the pickup and set it to the original specs. Will look up how to time it and make sure it's in time....my question is will the magnet that spins....will it rotate on that shaft or is it splinned? So the little black box that the screw backed out of (pickup)....that adjustment is for timing advance only?

It rotates on the shaft slightly because of the centrifical mechanical advance..this should also be checked to make sure it's moving easily. Not siezed of damaged because of the loose screw

Manns50
10-17-2011, 12:23 PM
Ok thanks guys will get on this after work today.

Manns50
10-17-2011, 07:10 PM
The screw that backed out was one from the little black box (I'm assuming is called the pickup) above the rotor magnet....Which does not have slotted holes. Havnt had time to look at it or measure the gap between the two but it looks more than the specified amount. Also the magnet spins freely on the rotor by hand...is this normal? I couldnt see how it would be. But it still turns when the rope is pulled.

Manns50
10-17-2011, 07:32 PM
Ok went checked the one I have for parts and figured it wasnt supposed to move freely....Lol. Pulled it apart and it sheered the key from the shaft I guess when the screw caused it to bind. The whole assembly reminds me of the old vacuum advance on cars....pretty basic. But my question is it couldnt have bent a valve by losing timing correct? This shaft is just for the ignition pulse....the timing chain would be controlling the valve timing.

dougspcs
10-17-2011, 08:01 PM
Ok went checked the one I have for parts and figured it wasnt supposed to move freely....Lol. Pulled it apart and it sheered the key from the shaft I guess when the screw caused it to bind. The whole assembly reminds me of the old vacuum advance on cars....pretty basic. But my question is it couldnt have bent a valve by losing timing correct? This shaft is just for the ignition pulse....the timing chain would be controlling the valve timing.

It was just your spark timing that was affected not your valves..your engine in intact.

The spark going out of whack makes the engine make rude noises that would make you think you threw a valve..no worries.

EarlyBronocGuy
10-17-2011, 08:46 PM
Yep, that tiny pin is only for the ignition rotor timing. Pull the rotor off the shaft and use a magnet or small needlenose pliers to get the piece of the pin that's still in the shaft out (if it hasn't already fallen out). Install new pin, put rotor back on shaft, use a non-magnetic feeler gauge to set the pulse generator gap to about .012" (the small black box that sits above the rotor, the screw holes are slightly slotted), you should be good to go.

oscarmayer
10-18-2011, 09:40 AM
if the shaft hole is wobbled out, you must replace the cam, but this can be done w/o takng the head off the bike, so your lucky. ;)