TCI Replacement 2020 It Works

maraakate

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I'm having good luck with the Honda MP08 coil with the GN box. You can usually find them used on Ebay for 20 bucks and under.
Maybe we should have been clearer. Run one or the other as resistor... just not both.

Is the MP08 a direct bolt on or do I have to fab some kind of bracket? They are cheap and plentiful, and allow replacement plug wires so this might be a good, cheap, reliable upgrade if there's not too much work involved on my end of things.
 

Team Junk

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I wanted to be able to 're-use' the wires/8-pin connector by re-attaching them to another replacement gonzo. The adapter pictured shows 6-pin to 6-pin, and I'd need a 6-pin to an 8-pin if possible, more like the diagram vs the photo.

These are the size and style connectors I use.
https://www.amazon.com/Automotive-E...&keywords=6.3mm+(6+Pin)&qid=1621926343&sr=8-9

Legend has it that the 6 pin pigtail will plug into the 8 pin connector. The 6 and 8 pin are the same except for the extra wires for the side stand and clutch switches which won't work with the Gonzo anyway. Look at the wire colors to figure out which side of the 8 pin connector to line up the six pin connector. I think there might be a photo in this thread somewhere that shows how it works.

Or you can pull the pins and wires from the OEM 8 pin connector and put them in a 6 pin shell like port did to connect to the Gonzo. That for practical purposes is what i have done on my bike.

This is where the Gonzo folks hang out so a good place to ask questions.
 
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Wharfcreek

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Jack, thanks for that info. I'll check it out. BTW, I jumped on to this thread here almost by accident. I'm somewhere back around page 11 in my reading of the whole thing. At 61 pages long.....a lot to digest. But, I wanted to make sure I was subscribed to it, so I figured I drop a quick post in here at the end. I didn't know you'd referenced me from the other thread.....but....per the 'let's keep all the Gonzo stuff here' request....here I am.

Anyway, this is all great stuff, and I'm diggin' the hell out of it! I can't wait to try my Gonzo unit here in the next day or so. I'll report it's function as soon as I have it connected. Unfortunately, I won't be able to give any 'ride quality' comments, as this bike project just isn't that far along. I don't even have the carbs back on the engine yet, nor do I know if the trans / clutch componants are any good. Just getting the engine to fire was enough of a problem, but I've managed to do that with a functional TCI box and some starting fluid. Now to try it with the Gonzo box. My biggest problem is that I don't have a title for my bike! It was a junker / basket case, and I'm bringing it back from the dead. I only hope I can find a way to ride it when I'm done!!

Tom
 

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BTW Tom. I'm going to steal your description of the Gonzo pins as you are spot on their functions.

One thing I will mention is the pickup inputs are a balanced input. The reason the input is polarized is the positive going pulse from the pickup must be first.
 
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Wharfcreek

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Jack, was it you or Jim that 'scoped' the pickup pulse? I'm just curious about the 'neutral' or 'ground' reference point. I'm thinking that if viewed on a scope or even measured on a sensitive DVM, connecting the two pickup leads ( b/w & w/r) one way would produce a 'foreward' or positive pulse and reversing the leads would produce a negative pulse. But I may be over-thinkin' it!!!
 

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Jack, was it you or Jim that 'scoped' the pickup pulse?

Both of us actually. There have been reports of boxes that had a grounded input pin I've not seen one. The pickup coil produces a ac signal that goes both positive and negative. As the magnet approaches the pickup the signal goes high in one direction( negative or positive) and then the same in the other polarity once the magnet passes the pickup. I think I know which pin is the positive input but want to confirm what I think is the case before it's cast into stone here.
Playing with new (cheaper and easier to find ) pickups and will have more scope traces soon.
 

Jim

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Wharfcreek

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If that black/white wire is, in fact, part of tbe electrical ground circuit on tbe rest of the bike then I can see it causing even more grief if not properly polarized with respect ito its connection to the TCI box. I can see where it could potentially cause a failure of the switching transistor altogether. Either way, I think you've built a more-than-sufficient case to support that pickup polarity is critical. It might be nice to know if thats all it is, or if electrical grounding is also a critical part of the pickup circuit. In other words, it may be necessary to have BOTH proper polarity AND a ground reference within the pickup circuit....or not. It may be the opposite, where having a ground reference is not only unnecessary, but potentially or actually damaging.
 

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It may be the opposite, where having a ground reference is not only unnecessary, but potentially or actually damaging.

On both the stock TCI and the Gonzo grounding one of the pickup leads is not a good thing because that would unbalance the circuit causing it to be subject to noise interference. The ground some people are reporting I now believe are filtering components on the inputs that provide a path to ground for the ohmmeter. Perhaps a diode is involved which would provide a dc ground in one polarity.

The pickup circuit is AC not DC like everything else on the bike with the exception of the stator coils.
 

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The black and white wire is for one of the safety switches (probably the side stand switch) I think grounding the black and white kills the ignition. Make sure the black and white is not at ground with the sidestand up.
 

Wharfcreek

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gonzon-instal-jpg.171263


Jack, the attached photo shows the Black/white (white/black?) wire in question here. I don't think this has anything to do with the kick stand kill switch. If I'm not mistaken, it's the 'common' wire between the two pickup coils, with the remaining two being the white/red and white/green. Please correct me if I'm wrong about this. But, this is the subject wire that I'm wondering if any continuity to frame ground is a designed-in part of the circuit......or conversely NOT to be connected to frame-ground (electrical ground or (-) batery voltage). I am going to guess it's a discrete circuit with it's only connection points being at the one end with the two pickup coils and the other end terminating at the TCI. I say this somewhat on the basis that the TCI also has a black wire representing 'ground' going to it, so if the black/white wire did need a ground reference it could get it internally within the TCI circuit. But, I've also noted some of the pickup mounting where it looked like the black/white wire terminated in a small metal tab the screwed to the stater housing. If so, then maybe it IS part of 'electrical' ground. Either way, just putting it out there for consideration. Not trying to muddy the waters here, and perhaps not an important item at this time. Bigger fish to fry.......so to speak!! Tom
 

5twins

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Take a look at an '82-'83 wiring diagram. These are the two models that had the sidestand switch and relay. Look at the relay. It has a B/W wire coming out of it and running to the TCI. This is that oddball 7th wire on the 7 wire TCI units.
 

Wharfcreek

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Its confusing! Black w/ white tracer Vs White w/ black tracer? Im just looking at the pickup sensor itself. I have one off a bike now and I'll do some checking on it and see if I can offer anything of any usefullness. Right now Im thinking that the 'stock' pickup's 'common' wire is a completely different circuit than that of the side-stand switch, but I build amplifiers, so I may be looking at this all wrong!!
 

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2M came and hung out yesterday and lots of discussion about the Gonzo. The good news is he took home a working Gonzo RM-1 system.He has much better test equipment. I'm starting to suspect that the NEO magnets need a lot more flying height to keep from over loading the Gonzo input. He suspects my scope has 10x probes not 1x. that would put the coil - ringing at 200v not 20 and the output of the pickup at 7-10 volts not .7 to 1 volt.

Plan on doing some calibration today.
 

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Right now Im thinking that the 'stock' pickup's 'common' wire is a completely different circuit than that of the side-stand switch,

That is correct. The sidestand 7th wire is a inhibit signal that when taken low (grounded) shuts off the coil- signal stopping the spark.
The pickup wiring is totally separate and the 3 pins from the stock TCI pickup only connects through the harness to the inputs on the Hitachi TCI box.
Same with the Gonzo system. The idle pickup coil connects directly to the inputs to the Gonzo. No other connection from the pickup to anything else
 
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