83 Heritage Special TCI troubleshooting

I have created a pc storage scope in the past, but they are not great. They are a cobbled together bumble-gum and haywire setup. It is running on an old laptop with it's own issues. I did try looking at the igniter using my scope, but it is hard to see what is happening. About the best I could do is note that the horizontal was triggering, so something is getting through, but whether it is noise or a weak pulse??? I think when I get a chance I will find an old signal generator and test the unit on a bench under more controlled conditions. For now I just need to get the bike running. The existing coil on my bike is at about 2.9 ohms. It is not the original either. I installed it a few years back when the original went bad. I measured the resistance on the primary on the new coil...4 ohms. I also tried running the TCI igniter with the new coil... nothing... not even a weak spark. Just have to get the pamco up and running. Got to find my timing light. Haven't used that in years.
 
There's a bumper crop of small, hand held, mini storage oscilloscopes on eBay.

I got one, a DSO201, about 4 years ago, shown here.

Post #8.
http://www.xs650.com/threads/alternator-rotor-inductive-kickback.42605/#post-426929

A newer version, DSO211, is about the same price, and supports 2 input channels.

https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/253330063939

In this thread, you can see the signal traces for points ignition, and for TCI ignition starting at post #49.

http://www.xs650.com/threads/an-led-ignition-timing-light-experiment.44586/

I suppose you could *probe* the signal driving the Darlington, to eliminate it from the suspicion list...
 
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Got the pamco kit installed, only a couple of hitches with the install. I hope to hook up the busted igniter module later this summer when I get time. The power, ground and connections to the pickup coils are still there. I just won't have it hooked up to the ignition coil. It will just run independantly of the pamco. I will try to capture some measurements with my oscilloscope and either video them with my camera or record them on paper. It would be nice to have a storage scope, but I don't. I will see what the pickup coil signals look like on the igniter as well as whether there is anything coming out of the IC. I suspect the IC is fried, but will see.
 
Got the pamco working using my TCI coil. Works fine so far. Will troubleshoot my igniter when I get a chance. As for the Igniters on Ebay, I did look a bit at them. You guys in the states are luckier. I have to think twice before buying stuff over the border. The general rule of thumb for me is to double the listed price on Ebay. That will account for exchange rate, duty, tax and shipping costs. I could get a new pamco from a Canadian supplier(with guarantee) with free shipping or a used igniter from across the border with no guarantee for about the same cost. That's not to say I never buy anything from south of the border, i just have to weigh the costs a bit more.
 
From yamahaxs650.com
The PAMCO Hall Effect E-Ignition system is a direct replacement for the points plate and points cam system on a Yamaha XS650. It can also be installed in later models of the XS650 that have a factory TCI system.

The system requires the use of a dual output coil. The stock coil in the TCI equipped models may be retained when installing this system.

Note: Use either resistor spark plugs or 5K resistor spark plug caps.

Specifications:

Technology: Hall effect sensor, IGBT coil driver, MCU E-Advancer

Dwell: Fixed, 60 degrees
Coil primary resistance: 2 to 5 Ohms, dual output.
Operating voltage: 8 to 18 VDC
Operating current: 13 ma
Operating Temperature: -40 to +125C (-40 to 257F)
Spark Advance: Electronic
 
I purchased the basic unit without the e advance. I don’t recall whether there was a Pamco label on the circuit board. there was some kind of etched logo on the back side of the mechanical advance plate. Couldn’t quite decipher the logo. The only problem I had with the kit was the thread on the large nut was incorrect. The nut thread was probably trapezoidal instead of a v thread. Basically, I could only get the nut on about one turn. XS direct sent me another nut and I was able to tighten down the advance plate. To be honest, the bike seems to run better with this setup. Definitely starts easier than with the old TCI igniter. To go and look for a label on the Hall effect circuit board now , I would have to disassemble it. I could see that XS direct was selling Pamco kits alongside their own kits. I assumed they were authorized to sell the Pamco kit, and they were selling off old stock. They were both the same price and I chose the kit that they called Pamco, assuming it would be better. Wouldn’t surprise though if XS direct is mixing and matching their kits with Pamco s.
 
Your schematic gives me a good idea for a hidden kill switch. If you have the later ver. TCI just wire your switch to the kickstand wire of the TCI. If you have an earlier one, it's probably easy to modify. I've been thinking about a hidden kill switch so maybe I will do it and make a tutorial.
 
Your schematic gives me a good idea for a hidden kill switch. If you have the later ver. TCI just wire your switch to the kickstand wire of the TCI. If you have an earlier one, it's probably easy to modify. I've been thinking about a hidden kill switch so maybe I will do it and make a tutorial.
That might work. Be cautious though. In hindsight, My interpretation of how the circuits work may not be accurate. The manuals say that the later TCI modules send a voltage to the starter cutoff circuit, not the other way around which is what I assumed. All I know is that the bike runs better with the kickstand relay disconnected. I did spend one afternoon trying to puzzle out how all that worked, but gave up. The wiring diagrams and descriptions of the circuits in the manuals are vague at best. This may sound odd, but the intent of a circuit design and how it actually works and sometimes how it is described aren’t necessarily the same. Sometimes this is deliberate, sometimes it is just a dumb design. If you do hook it up, do it through the kickstand relay. When I get a chance I will go over my notes and chicken scratchings and try to get a better understanding of it.
 
In that case, if you get a chance just check the circled area. I will see if it makes sense, sometime, but I will have to dig out the books to do it.

TCIschematic 83xs650.png
 
I don't understand why a pma is considered an upgrade, I am of fan of the 80s and up because of the tci, I also know some like the crank timed ignition as well which is how our stock tci s are.
Why is the pma an "upgrade" to some people?
 
In that case, if you get a chance just check the circled area. I will see if it makes sense, sometime, but I will have to dig out the books to do it.

View attachment 143497
Just back from a weekend break and starting to look into this. To begin with, I think your idea will work, but I didn’t want to tell you to go ahead and find out later that you destroyed your TCI based on my recommendation.
My TCI circuit drawing is based on some assumptions, one of them being how the side stand relay interacts with the TCI module. The side stand relay is missing from my bike. Looking at the four wires connect to that module, I made an assumption. I still think it is the correct assumption, but I have no way to test it myself. Of the four wires there is L/Y which is the ground signal from the side stand switch(ground when sidestand up) and R/W which is +12v. These two wires probably energize the relay. The B wire is chassis ground which probably gets switched through the normally closed relay contacts to the W/B wire which goes to the TCI module. In other words when the sidestand is down, the relay is de-energized and a ground is switched through to the TCI, disabling it. When side stand is up, the sidestand switch is closed energizing the relay, opening contacts, removing ground from TCI, allowing it to work.
None of this info is in the Haynes or Chilton manuals and when I was skimming through the Haynes manual last Friday to see if I missed anything I came across a reference saying the TCI module sends a voltage to the starter cutoff relay (chapter 7,sect 26,para 5). This threw me for a loop and I needed to reread this a few more times. I believe this is a mistake. The cutoff relay is getting power from the AC gen not the TCI.
Finally, I looked in the operators manual that came with the bike. They refer to a “Ignition cutoff circuit” controlled by the sidestand. I believe this is an accurate description of this circuit. Unfortunately they don’t show it or describe it in the manuals.
If you are going to hook this up, do it through the Ignition cutoff circuit(sidestand relay). Your way will probably be better than having a cheap switch down near the sidestand, contaminated with oil and dirt.
I am pretty sure of the wiring of my TCI module, but I will check it again when I get a chance. Keep in mind that there seems to be different versions of these modules out there.
When I get time I will post a diagram of the Ignition Cutoff circuit, or at least how I think it is wired up.
Send me some pictures of your work
 
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Just uploaded my interpretation of the ignition cutoff circuit. This circuit is described briefly in the owners manual, which I have included. It is not really discussed in the Haynes or Chilton manual. The haynes manual has a very good description and diagram of the Starter Lockout circuit in Chapter 7, page 160. They stop short of describing the Ignition cutoff circuit. I would have liked to include my doctored version of the Haynes diagram, but suspect that might compromise some copyright law?
I haven't been able to confirm the accuracy of this circuit. My bike is missing the sidestand relay. It was probably stomped into a thousand pieces on the side of the road in a fit of rage by the original owner. Somebody still have this on their SK? Maybe they could check the accuracy of this.
 

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I don't understand why a pma is considered an upgrade, I am of fan of the 80s and up because of the tci, I also know some like the crank timed ignition as well which is how our stock tci s are.
Why is the pma an "upgrade" to some people?
Well basically the stock alternator is weak. The quoted specs are hard to nail down. Some of what I have is: Over 16 amp at cruising rpm, 11 amp at 2000 rpm, 10 amps at 1000 rpm, falling off more at idle speed. If you total up the expected load just by tallying the current drawn by the various lamps, headlamp, tail, brake, indicators, signal you will find that at idle there is not enough current to run the bike. At idle, you are relying on a good battery to supplement the alternator to keep the bike rolling. I remember sitting at an intersection, with the signal light, and brake light on. The neutral and other lights were flickering along with the signal light and the engine ignition was struggling. I did some static measurements of the current drawn by various parts of the electrical system. My static measurements closely matched what I expected. You need to run at over 1000 rpm to keep from stalling. To fix this, I have replaced what I can with LEDs, removed what I don’t need such as license plate lights and bought a really good battery. It runs a lot better now, but a Permanent Magnet Altenator might provide more current at idle and higher speeds. Unfortunately, you have to replace the TCI when you replace the stock altenator.
 
The voltage stays close to 14 if you're rollin, meaning the generator is up to the job. The problem you're going to have is finding a quality PMA, probably, not PMA is inherently worse. That's where all the cautions are coming from.
 
Okay, got it. Yes same here, in bad traffic especially, my bike is stalling at idle due to not enough power to the ignition. I have to idle at like 14-1500 rpm to keep up.
 
Okay, got it. Yes same here, in bad traffic especially, my bike is stalling at idle due to not enough power to the ignition. I have to idle at like 14-1500 rpm to keep up.
Do the basic tests to check the charging systems. Check the battery. If the altenator/reg and battery are ok but you are still having issues, try running the bike with the headlamp temporarily disconnected for a short run. With the headlamp disconnected there will be a huge drop in the load on the electrical system. If the bike is now idling better this may indicate the same trouble that I was having... basically the charging system is anemic. I replaced all the lights Except the headlamp with LEDs and it runs a lot better. Be forewarned.... there are a different set of problems with using LEDs.
 
I changed my license plate lights to LEDs already and have my eye on a nice LED tail brake light. Idk about signal lamps. I'll do the tail brake combo and cluster and gauge lamps and see how that does me. I am running rich as well I gota get back in my carbs and go back to stock size on pilot jet.
 
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