New here but I've been reading...

Oh so then yeah of course I still have a few connections to clean too. I don't have any contact cleaner on hand but the plan is to check the grounds and clean the connections properly. I'd like it to be just the switch and I went through the great troubleshooting guide step by step with the exception of cgetting all the connections clean and opening up that switch. Thank you. I should have some money tomorrow and contact cleaner is first on my list.
 
Doomed2ride said:
At TDC it will fire when I switch from run to stop.
Click to expand...
You might be going down a rabbit hole. Sounds to me like the coil pri. is charging and when you hit the kill switch (which supplies power to the coil), you're effectively using the switch as a set of points.

Coil primary charges.... open points (or kill switch in this case), secondary discharges.
 
S
JimD54 said:
You might be going down a rabbit hole. Sounds to me like the coil pri. is charging and when you hit the kill switch (which supplies power to the coil), you're effectively using the switch as a set of points.

Coil primary charges.... open points (or kill switch in this case), secondary discharges.
Click to expand...
so maybe the secondary coil is malfunctioning? It tested at over 20,000 ohms at the plug wires, which I thought was odd.
 
I think Gary and Jim have got it here. You can clean the switches, but the problem is elsewhere as Gary said.

I remember a Cycle magazine article where the guys were using the kill switch to cause loud backfires. Small alleys, between tall buildings with lots of windows, was their favorite place to do this.

Scott
 
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The pickup would be a cheap thing to swap out. If that's the problem That would be OK. The TCI, however... I don't know when I could afford another one of those. Loud and clear I hear y'all saying you've seen the spark on shutoff before. Totally makes sense that the switch is acting as points. I never got anything like a spark except on shutoff. I will clean connections and if that does not improve things, I will replace the pickup. Thank you all for the advice.
 
I'm really glad You guys have this forum! I'd be chasing my tail a lot. OK so the coil is good. That's a relief. I checked the resistance on the pickup and it was good but if there's another test I can do I'd love to know. Thank ou.
 
Doomed2ride said:
but if there's another test I can do I'd love to know. Thank ou.
Click to expand...
Did you try as I suggested earlier to disconnect the alternator?
That might tell us if it's a weak trigger (pickup) magnet.
 
I haven't disconnected the alternator yet. I'm not sure how to do that. I'll try it though.
OK Now I disconnected the alternator and kicked it over a few times. With the spark indicator installed I saw the same spark on cutoff.
 
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On the downtube... behind the carbs. There's 3 connectors. 1 single bullet (goes to safety relay... yellow wire), a 3 pin connector (that's the TCI), and a 6 pin connector.... that's the alternator. Disconnecting that one might tell us if the trigger magnets weak because it will kill the alternators magnetic field and allow the triggers magnetic field to get picked up..... maybe.... hopefully.

And as Gary said... low batt. voltage will cause the TCI to go all screwy on ya.... Make sure the batt. is fully charged.
 
Means you still haven't told us what your batteries reading...:rolleyes::whistle:
You said your pickup ohm'd good. if that's true, it's leaning toward the TCI box OR the wiring/connections.
 
Oh. Oops, sorry. It's a new battery from Napa fully charged reading about 13 volts. IT cranks the starter just fine. I have the old battery at 12.7 volts.
 
Well... I'd continue with cleaning up all the connections.
 
OK Thank you. That's the plan. Contact cleaner and a toothbrush will go to work. It may very well be a crappy connection anywhere in the chain. I have the original owner's manual so I have the wiring diagram. Not a bad way to spend the day.
 
Doomed2ride said:
OK Thank you. That's the plan. Contact cleaner and a toothbrush will go to work. It may very well be a crappy connection anywhere in the chain. I have the original owner's manual so I have the wiring diagram. Not a bad way to spend the day.
Click to expand...

You know, many of the issues we have with these dear old bikes boil down to dirt, rust, schmutz and general sh!t that has collected here and there all over them for the last 40-odd years. The more of it you can get off and out of, the bike, the better it will work.'

Keep at it - you're getting there Doomed!

Pete
 
Even if it's the TCI that is probably fixable. I repair old tube radios and the TCI isn't too crowded on the board. I saw some great stuff about repair on the 650 Rider boards with great pictures. That connection at the wire looks pretty hokey and I would not be surprised if there were a bad connection going into the box. I'm still going to clean connections. After that, if no spark shows I'll dismount and check the TCI.
Helpful video about the ignition system:
 
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The multi-pin connector blocks for two of the most important components on the bike, the reg/rec unit and the TCI box, are along the left side of the battery box. There, they can be exposed to battery acid or just the acid fumes, and get all corroded. The ones on my '83 were pretty crusty. A couple of the spade connectors even broke while I was removing them from the blocks and cleaning them. I guess the acid exposure and subsequent corrosion weakened them.
 

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