Quick tdc question...with picture :D

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Scgoobertn

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Just a quick confirmation, really just double checking myself. *IF* this hasnt been messed with before this should be the correct tdc markings lined up? View pic
20130317_152911.jpg



Thanks!
Goober
 
Yes. The U shaped mark over to the left is the idle timing mark. If you use a timing light the rotor mark should be between the two legs of the U.
Leo
 
Thanks Leo! The bike was a non runner when i got it. When i went over it i could see it was plagued with electrical issues (some PO rigging going on). Pulled the motor and stripped the bike while waiting on the title. After a month and many trips to the tag and title office, got the title. Now since i have the motor on my bench i figured i am going to install the PMA and try and rig some way to try and get the motor fired up before spending any money elsewhere. Anyways thanks again
 
If you just want to hear it run all you need is the ignition. That's an 80 up stator so I assume you have the TCI that goes with it. If so swapping to the PMA you will need to swap the TCI for another ignition. The TCI is a good ignition but it needs to use the stock stator and rotor. The TCI uses a pickup on the stator and a magnet in the rotor to trigger the TCI.
If you have the TCI box get it wired to the pickups and coil. Hook up a battery with negitive to the engine case, positive to the red/white wire at the coil and TCI box. This should get it to run.
Leo
 
Here's what it looks like under all that rust, lol .....

TDC.jpg


IdleTiming.jpg
 
Slip rings look as if they could use a little clean up as well. Some metal polish (chrome cleaner or Mothers) and a little rubbing cleans them right up. Here's mine with one cleaned, one not .....

OneSlipRingClean.jpg
 
Thanks, The wiring on the bike was a complete wreck, so i opted to pick up a hughs pma and pamco ignition. Just got the Rotor off, no oil behind it yay! Gotta go pick up some dinner for parents then gonna finish up installing the pma and do some reading up on the pamco install (motor parts wise). I got a lot of work ahead of me lol, i have never really had to mess with carbs (except my stand up jet skis, and even then i never ever had to sync or rebuild them) this is exciting! :D

thanks for the pics and the help. I was pretty sure i was right on, but at the same time i did not want to assume that i was right.

Thanks again
Goober
 
At some point in your work, it may be worthwhile to confirm TDC, just for "peace of mind" - the "tool" is easily made from a spark plug shell, and the procedure is easy to find on this forum. On TCI motors like yours, the full advance point is NOT marked, like it was on earlier points ignition motors - I think because the TCI system was not considered to be adjustable in service. Recently, someone on the forum (I think it was 5twins) informed us that the full advance mark (40 degrees BTDC) aligns with the left edge of the small square cut in the left hand case cover. After installing your new ignition system, you may want to check full advance (approx. 3000 rpm) to ensure that it does not exceed this spec. (5twins, please correct me if I mis-remembered and have mis-stated what you said about finding the 40 BTDC point.)
 
You are correct about the full advance location but I'm pretty sure this info first came from Pamcopete, maybe I just re-stated it or passed it along. I did "doctor" up a pic to illustrate though .....

Advance.jpg
 
This is one of those pic's that definitely is worth a 1000 words - thanx, and thanx to Pamcopete. I used this information to double-check a full-advance mark that I had laid off measuring 3 successive half-inch increments to the left of the TDC line on the tab, in order to time the Boyer-Brandsen ignition that I got last summer. It was spot-on; good for my peace of mind regarding such a critical adjustment. I suppose it would be possible to swap the short "TCI" timing tab for an earlier one that shows full advance; dunno if it's worth the effort at this point for me.
 
I'm not sure that's possible. On the earlier models, the timing marks are actually cast into the alternator housing .....

FullAdvancePoints.jpg
 

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