TCI Replacement 2020 It Works

Something odd happened today. Ran the GN box on my 650 down to check the mail...about a 2 mile trip. Started and ran fine on the way there. Shut it off for about 3 mins while I checked the mail. Went to start it and it backfired and no start. Tried starting it again and it ran but then would spit, sputter, and backfire whenever I tried to take off under load. Idled fine. I should have shut it off and tried to restart it but needed to get home so I swapped the TCI back in and it ran fine. I'm guessing the timing on this floating GN unit went bonkers? Will try to reconnect it and see if it does it again.
 
2XSive said:
Something odd happened today. Ran the GN box on my 650 down to check the mail...about a 2 mile trip. Started and ran fine on the way there. Shut it off for about 3 mins while I checked the mail. Went to start it and it backfired and no start. Tried starting it again and it ran but then would spit, sputter, and backfire whenever I tried to take off under load. Idled fine. I should have shut it off and tried to restart it but needed to get home so I swapped the TCI back in and it ran fine. I'm guessing the timing on this floating GN unit went bonkers? Will try to reconnect it and see if it does it again.
Click to expand...
One of my biggest fears on this whole endeavor is that we're dealing with a $15 part..... that's made in China. :cautious:
Keep us poster Larry.
 
2XSive said:
it ran but then would spit, sputter, and backfire whenever I tried to take off under load. Idled fine.
Click to expand...
That's a good description of what mine did when I disconnected the alternator. You notice whether or not it's charging OK?
 
So I couldn't wait to get back out in the garage and hook it back up. Started and ran fine. Took it for a 3 mile spin and ran great. Go figure. Will see if I can duplicate it again. Thinking the GN picked up a bad signal from the TCI pickup upon initial restart at the post office.
 
6mm neo magnet GYT6 Pickup 153 Ohms coil resistance.
Notice the peak voltages on right.

720 RPM 5100 RPM

upload_2020-6-25_14-3-32.png upload_2020-6-25_14-5-29.png
 
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When I was out and about yesterday, other than a stumble from rolling up throttle from idle the Ol' SG just glided along. I believe the stumble is from the really retarded setting. I will confirm this later today (I hope). I also believe this is why I ran out of gas yesterday too. She withstood the 105*F and she almost always started easy. Never more than 3 tries and she was idling. I'm going for a almost max advanced position and see where the idle setting is. This should get me no more stumbling off idle and my gas mileage back. It's only 130-140 mile round trip to the Tom Mix Memorial and should have easily done it with gas to spare on a Standard's 4 gal. tank.
 
5100 RPM
upload_2020-6-25_14-56-34.png


3600 RPM Can see the 3mm magnet !!!! The voltage on the 3mm is less than it could be, the pickup flying height is very high to clear the 6mm magnet and accumulated JB Weld
upload_2020-6-25_14-59-46.png
 
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TJ, your going to get me in trouble. On my KZ/GPZ project I can see me locking the mechanical advance and use 2 Gonzo's boxes to serve as the ignition. One for each pick up. The pick up is magnetic and a steel pointer goes by to signal the spark. OOOHHHHHhhh.
 
Ok. Made 3 or 4 runs up to 5100 RPM with one the floaters. Timing move up and down with RPM smooth as butter. No weirdness at all.
Jim, It's got to be something ether in the TCI pickup or the magnetic field from the rotor. Looking at the scope traces with the neo magnet it looks like the voltage is high but no current. Too low to measure on my 10 amp meter. Perhaps .001 amps. That's why the RMS voltage is so low.
 
Team Junk said:
Jim, It's got to be something ether in the TCI pickup or the magnetic field from the rotor.
Click to expand...
I'm thinkin' door #3... the box is bad.:doh:
It's not the rotor's field because I disconnected it. Don't think it's the pickup either.... 10k resistor didn't make any difference. Jake is gonna loan me his floater box for testing... so we'll see that on my bike shortly.
 
This is trace from my stock tci pickup and magnet. . Notice how the negative pulse is distorted. I'm pretty sure that's the influence of ether the advanced coil ringing or the rotor's field.


upload_2020-6-25_16-24-48.png


Edit

The voltage on the stock pickup is a lot lower.14-16 Vpp
Edit the edit. I misread the voltage levels. I was using 1V divisions. It's .5V not 1
So looks like 7-8Vpp
 
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Team Junk said:
This is trace from my stock tci pickup and magnet. . Notice how the negative pulse is distorted. I'm pretty sure that's the influence of ether the advanced coil ringing or the rotors field.


View attachment 170649
Click to expand...
Is the rotor powered while you're testing it? Try killing power to it and see what happens.
 
I'm trying to keep up. Lol
I'm not as knowledgeable with electronics. What is meant by "floatin".
Thanks for keeping us posted on this endeavor. I'm looking forward to a positive end, and a condensed tutorial in the tech section.
 
I can't it's been a couple months since my starter failed. I think I was just turning over with no power to rotor (I think).
 
On test stand
Non-rev 0
+ pickup to 3 on gonzo
- pickup to 6 on gonzo

Stock TCI pickup coil.

80 to 81- Measure between black/white and the white/red leads and between black/white and white/green leads Both should measure 550-850 ohms

'82 to '83. Measure between grey and black leads and between orange and black leads. Both should measure 630-770 ohms.

GYT pickup on test stand. 153 Ohms
RX135 pickup. 300 Ohms


To kill the ringing I think trying 1k across the advanced coil should kill it.
 
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