TCI Replacement 2020 It Works

Thought 1: If you know someone with a GN250 put a scope on it to see what input signal the stock ignition was designed to work with, then plug in a Gonzo and compare. At present it seems that the XS TCI stock sensor can fool certain Gonzos, but the Gonzo was probably designed to accept a reluctor signal where the +ve and -ve peaks are separated by a time related to the angular length of the raise metal sensor strip on the PMA rotor which then defines the pulse length. The length of the raised metal strip does not increase the signal strength. The strength is related to the change in flux. The flux only changes at the start of the raised metal strip and at the end of this strip. The length of the raised metal strip defines the separation between the +ve and -ve peaks which on the stock GN250 ignition defines the pulse length. For all I know the pulse length on the GN250 may be defining "dwell time" for the coil.

Thought 2: If the GN250's raised metal sensor strip on the PMA rotor maps out a similar number of degrees as that between the two coils on the XS's stock sensor then you may be able to trick the Gonzo by putting a diode on each coil to obtain a +ve peak from the first coil and a -ve peak from the second. Both diodes will then get tied together at the Gonzo input. The Gonzo will then see this as a reluctor style signal and generate a pulse with the correct length. I realise this looks a bit like a short circuit because the signal from one coil feeds the other coil plus the Gonzo input. But just maybe ...
 
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you guys are onto something great i think, but you need to fully understand it or it didn't happen... and when you fully understand it, all problems will be much easier to fix
 
Guys I just got my box in the mail today. Readings look to be trigger is grounded as showing continuity. Please confirm. JC

63B655ED-8230-464C-8417-9FF35913C74B.jpeg
 
Hey guys, I'm jumping on board the Gonzo wagon. I too have a grounded box so you can add me to the list. I am installing mine on a 1981 XS650 Heritage Special. Rather than using a jumper, I backed the pins out of the wiring harness TCI plug and will be plugging the Gonzo box directly into the harness. I have it all wired up, waiting on my battery to charge before I give it the first go. I have two questions:

1) Is there a concern with the Gonzo overheating if mounted under the seat in place of the Emergency Headlight Box? I haven't seen thermals mentioned in the thread.

2)Can I get a confirmation that I wired up to the Gonzo correctly? Pretysure that I got it but might as well ask.
IMG-1065.JPG
 
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1.) No, heat shouldn't be a concern. I've done an hour+ with a 100°+ heat index and it was still cool to the touch.
2.) Yes, if that's the factory wiring, you've got it correct.
Be sure and put a timing light on it and see where you're at on full advance. You really need to get to 35° advance or I suspect your millage will suffer. I had to file the slot on the TCI pickup to get there... actually I'm at 34°. I need to file mine a little more.
Once you test ride it, as much info as you can provide would be very helpful.
 
1.) No, heat shouldn't be a concern. I've done an hour+ with a 100°+ heat index and it was still cool to the touch.
2.) Yes, if that's the factory wiring, you've got it correct.
Be sure and put a timing light on it and see where you're at on full advance. You really need to get to 35° advance or I suspect your millage will suffer. I had to file the slot on the TCI pickup to get there... actually I'm at 34°. I need to file mine a little more.
Once you test ride it, as much info as you can provide would be very helpful.


Thanks, ill definitely provide an update.

Just to confirm, 35deg is the 6:00 position there the notch is, correct?
 
Thanks, ill definitely provide an update.

Just to confirm, 35deg is the 6:00 position there the notch is, correct?
I used a straightedge from the drain notch to the center of the crank in order to make a white mark on the case to bring the notch marks closer to the rotor.
It's a bit sloppy, so I'm going to do it over more carefully.

zzzCrankmark.jpg
 
I can't contribute to the electronic of this at all, but thought I would take day off from the bike and make a tool that aids in determining magnet location on early rotors. I set it up as a transfer punch, because it can then be used for any diameter magnet you may want to try. It also has plus/minus 5 degrees marked off for moving timing if desired. All you'll need to do is pick up an end mill to cut the pocket. If anyone is interested it giving it a try shoot me a PM and I'll send it to you. If it works out to be useful it can be added to the Floating Tools list.

IMG_1106~photo.JPG


IMG_1091~photo.JPG
 
Here is a summary of my testing with the Gonzo to this date:

I have (4) boxes, and all are the grounded type.
I have labelled them GN #1, #2, #3 and #4.

I connected GN#2 to my completely stock 1983 Heritage Special, and the bike ran smoothly on it right from the get-go.
A "plug-n-play", as someone remarked.
See post #631
http://www.xs650.com/threads/tci-replacement-2020-it-works.57388/page-32

Here is the video of the '83 prior to the introduction of the Gonzo (GN#2):


Here is the '83 with the Gonzo #2 connected:


Then I connected three of the Gonzo boxes to my nicely-running completely stock 1982 Heritage Special.
It ran poorly on all of them:
Post #788
http://www.xs650.com/threads/tci-replacement-2020-it-works.57388/page-40

Here is the video below of the '82 with GN box #2 connected, which is the same box I successfully connected to the '83:
see post #797


So, it would seem that there are 2 possibilities:

1. The '83 and the '82 Heritage Special models have some sort of subtle difference.
2. My '82 has some sort of glitch that disallows the Gonzo from working on it, but does not affect the performance with the stock TCI system.
.
.
 
I have a Gonzo mounted in my 81. I’m painting my tank so I haven’t been able to properly test it yet but it started right up and ran for a few seconds on what was left in the carbs. this post got me a little spooked so I went and checked the part numbers for my the pickup and the rotor across a few years. The pickup and rotor seem to be the same part across the Years but the ignition box changes parts between 81 and 82. Which makes me question why it wouldn’t be functionally the same.

1981:
https://partstream.arinet.com/Mobil...FNq1f4LXprzGATNl9wPtq8eElTnHeKO4SsvAN1w1.html

https://partstream.arinet.com/Mobil...KQkzsHQjufl6_s5aq_g1UbFTV5h7ItAK9PCFBhU1.html

1982:
https://partstream.arinet.com/Mobil...08lQYZcePmQs01h-OmafwiWSw06dPhlnKXimmrU1.html

https://partstream.arinet.com/Mobil...TW1ydMb7YxGSUPc0Ie3PnTAR_eaX56VMmScx42U1.html

1983:
https://partstream.arinet.com/Mobil...nYEG-p2MyuGRhTiHqFmHMl6My4JQjLvSgJ4yytU1.html

https://partstream.arinet.com/Mobil...7OC2_M1P4kGFcsEzuTdC4qOumTieJh12BL0Hz3w1.html

my apologies if those links don’t work on a pc, I’m on my phone rn. If they don’t work I’ll update then when I get back to town.
 
The '82 - '83 wiring harness and reg/rec part numbers are the same. (Partzilla source)

5V4-82590-50-00 harness
3G1-81960-A1-00 reg/rec
 
The difference in black boxes is because of an extra wire on the later ones for the sidestand safety relay. Other than that, I think they function the same.
 
Ok, so I went back and checked the following parts from '80 - '83. I have highlighted the items that are different than the previous year model. I don't see a complete system change at any point to it seems reasonable to think that the components are cross-compatible less the kickstand-switch. I attached an image of my spreadsheet so it it more visibly navigable and the text so that the links work. Let me know if there is a way to post tables, I couldn't figure out how.

upload_2020-7-11_12-23-2.png


1980 XS650 G

3G1-81600-10-00
Ac Generator Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/50041ec5f8700209bc786955/a-c-generator 3G1-81650-10-00
. Rotor Assembly
3G1-81610-10-00
. Stator Assembly
3G1-81671-10-00
Base, Pickup
https://www.yamahapartshouse.com/oemparts/a/yam/50041ed0f8700209bc786977/electrical-1 3G1-81960-A1-00
Rectifier/Reg Assembly
3G1-82310-60-00
Ignition Coil Assembly
4M4-82305-10-00
Ignitor Unit Assembly 1


1980 XS650 SG
306-81600-14-00
Ac Generator Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/50d48091f8700231c09cdcd5/ac-generator
3G1-81650-10-00
Rotor Assembly
3G1-81610-10-00
. Stator Assembly
3G1-81671-10-00
Base, Pickup
https://www.yamahapartshouse.com/oemparts/a/yam/50041bc7f8700209bc785ddf/electrical-1
3G1-81960-A1-00
Rectifier/Reg Assembly
3G1-82310-60-00
Ignition Coil Assembly
4M4-82305-10-00
Ignitor Unit Assembly 1


1981 XS650 H
4M4-81600-10-00
Ac Generator Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/50042085f8700209bc786eda/a-c-generator
3G1-81650-10-00
. Rotor Assembly
4M4-81610-10-00
. Stator Assembly
4M4-81670-10-00
. . Pick-Up Assembly
3G1-81960-A1-00
Rectifier/Reg Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/5004208ff8700209bc786ef7/electrical-2
4M4-82310-60-00
Ignition Coil Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/5004208ff8700209bc786ef6/electrical-1
4M4-82305-10-00
Ignitor Unit Assembly 1



1981 XS650 SH

4M4-81600-10-00
Ac Generator Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/50042097f8700209bc786f07/a-c-generator
3G1-81650-10-00
. Rotor Assembly
4M4-81610-10-00
. Stator Assembly
4M4-81670-10-00
. . Pick-Up Assembly
3G1-81960-A1-00
Rectifier/Reg Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/500420a1f8700209bc786f23/electrical-2
4M4-82310-60-00
Ignition Coil Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/500420a0f8700209bc786f22/electrical-1
4M4-82305-10-00
Ignitor Unit Assembly 1


1982 XS650 SJ
4M4-81600-10-00
Ac Generator Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/5004220df8700209bc7874d0/a-c-generator
3G1-81650-10-00
. Rotor Assembly
4M4-81610-10-00
. Stator Assembly
4M4-81670-10-00
. . Pick-Up Assembly
3G1-81960-A1-00
Rectifier/Reg Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/50042214f8700209bc7874ed/electrical-2
4M4-82310-60-00
Ignition Coil Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/50042214f8700209bc7874ec/electrical-1
5V4-82305-10-00
Ignitor Unit Assembly 1


1983 XS650 SK
4M4-81600-10-00
Ac Generator Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/500423e0f8700209bc787bdc/a-c-generator
3G1-81650-10-00
. Rotor Assembly
4M4-81610-10-00
. Stator Assembly
4M4-81670-10-00
. . Pick-Up Assembly
3G1-81960-A1-00
Rectifier/Reg Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/500423e7f8700209bc787bf9/electrical-2
4M4-82310-60-00
Ignition Coil Assembly
https://www.yamahapartshouse.com/oemparts/a/yam/500423e7f8700209bc787bf8/electrical-1
5V4-82305-10-00
Ignitor Unit Assembly 1
 
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