Alternative to hacking the harness?

[xs11bobber]

I'm working on an E(78std.) [along with my 2 SF's]

The spark kept running away. I've heard the bike run 3 different times. The pick-up wires were checked and with firm pulls the coatings didn't hourglass. 1 time, we removed the tipover switch and instantly we had spark. So it was assumed there was a short in the harness somewheres. A new(different but old) harness with all the workings was bought from a G that was stated to be a working harness.

The problem is the harness wasn't long enough to mount the TCI in stock location for a standard which leads me to believe it's not really a standard. The idea to just extend the harness with a scrap SF harness was thought up quickly and carried out the same. Upon reassembly, it's not simple color to color.

• The SF has 3 red/whites and 2 red/yellows
• The G has 3 red/whites 1 red/yellow and 2 Yellows
• And the rest are all the same I think

Is there any amount of testing that can be done to figure out what goes where? Also it's a 2H7 if that helps

[bikerphil]

A new(different but old) harness with all the workings was bought from a G that was stated to be a working harness.

The problem is the harness wasn't long enough to mount the TCI in stock location for a standard which leads me to believe it's not really a standard

In 1980, the Standard's TCI box was moved foward to the position the Specials always used. Only 78 & 79' Standards had the TCI way in the rear.

[petejw]

Hey Josh,
Ive been having similar problems with my bike lately,
had a miss typical to broken pick up coil wires, i began replacing
pick up coils, coils, leads, plugs, nothing fixed it, after messing around with the electrical connections that run under the tank, along the top rail frames, also played around with the fusebox and the connections behind it, not sure which wires were the problem, but the miss went.

[xs11bobber]

Thanks Phil. I didn't know that.

Hey Josh,
Ive been having similar problems with my bike lately,
had a miss typical to broken pick up coil wires, i began replacing
pick up coils, coils, leads, plugs, nothing fixed it, after messing around with the electrical connections that run under the tank, along the top rail frames, also played around with the fusebox and the connections behind it, not sure which wires were the problem, but the miss went.

Yeah, It seemed to be funky with tank removal back and forth before the harness swap. I sprayed all those connectors with electrical cleaner, took a hook and pick and scrapped a little on every one and then sprayed them again and it was still funky. I noted a flicker on the dash lights when touching the stock fuse block so I thought that was it. Installed T.C. block and thought it was cured and was deffinitely wrong. I tried putting my PNM coils/dyna wires/NGK caps on the bike and still no spark with the old harness. I don't know what the hell the deal is.

Is there a stronger cleaner out there for electrical connectors other than the CRC brand that someone could recommend? I can go through the old harness on the table AGAIN and maybe see if I can get it figured out before snowballs are hittin me in the azz. I think I'm gonna go try and conquer that task now...

[wa407mpp]

I use Permatex battery cleaner item# 80369, it's a foaming cleaner in a spray can ,you just spray it on and wait a few minutes, then flush it away with electronic cleaner. It cleans both the pins and the sockets without having to scrape or scrub. Everything comes out bright and shiny. I wouldn't leave it on too long though, pretty strong stuff.

[xs11bobber]

I went through the entire harness with a hook & pick set and CRC electrical cleaner. Spent about 2 hours on the seat forward area of the harness spraying scraping and re-spraying. Put the coils on the E from my SF which are the PNM "replacement" coils. Bypassed ballast resistor. Cranked and looked like I was getting around 22k ohms on each coil @ 57°F but spark on only 2&3. Sounds like pick-up wires to me, but I'm not sure. Clymers states 15k ohms between plug caps. Any suggestions?

[xs11bobber]

Primary resistance was 3.5 ohms with key off.
Key on - dropped immediately to 1.8 then descended down to zero ohms in about half a second.

[xs11bobber]

On Randy's website. The TCI Repair section. He says to hook the black to ground and then test the Orange and Grey for 10-11VDC then do the swing with an analog DVM.

I have a digital, but doing this without cranking I got 12.6 MV!!!!!! on the Orange. Which slowly dropped to 11.7MV while key was on. On the Grey I got a steady 9.4V. So neither of these are between 10 and 11 volts. Should I have the battery tested/swap for the new one I bought for my bike 2 weeks ago? Or is it something else entirely?

[TopCatGr58]

Hey Bobber,


Okay, let me see if I follow you, you put the newer PNM coils on the "E" machine that you are trying to get running. Have spark on only 1 coil/wire set. You bypassed the Ballast resistor because of the PNM coils=proper action!

You can't test the Primary resistance with it still plugged into the harness, you need to unplug it, then you should see about 2.5 ohms for the PNM coils. They do have a higher secondary resistance, so the 22Kohms is probably right.

Your 9.4 volts on the grey and the 11.7 Millivolts on the Orange looks to be the problem, you're not getting any power to the Orange circuit. You need to trace the Orange wire thru the harness to see where it's loosing connection. The TCI has 2 sets of connections that it supplies power to the coils with, one that is DIRECT to the coils, giving them 12 volts for easier starting, but once the engine starts, it shuts that circuit down, and sends it out to the other wire that goes to the Ballast Resistor.

Start checking your voltage at the ballast resistor, should be seeing 12 volts there WITHOUT the resistor. If not, then check the connections to the TCI, did you CLEAN those plugs and prongs at the TCI!?
T.C.

[xs11bobber]

T.C. You're the man!
No I hadn't yet, but just did that. Scrapped with a pick and scrubbed with a brass brush a little and sprayed electrical cleaner on it(TCI). Swapped out the battery next. It's brand new, never been on anything other than a battery charger, but it didn't seem to help much. Grey now gets 10.15V and Orange is still in the MV, somewhere around 35mv. At the ballast resistor bullet connectors with the new battery I'm getting 10.48V.

So if I understand you correctly, the orange circuit is one of the start circuits and you think I may have a short on that circuit in the harness? So that means the orange wire is hot? Which would make it getting power in the TCI? Could I use a test light to find where my power is going or... Is there a wire that should be hot at the TCI that should supply the Orange. Maybe I have that common solder fix problem Randy always talks about. I have swapped TCIs and got the same result though???

Man, this stuff is irritating as all get out. I've had the thing running 5 or 6 times now. Nothing more than an idle, but this spark thing has been an issue all along. My dad's bike is irritating me more than my own 2.

All the parts from his bike I know work because I've swapped with mine and everything was a go. Just replaced all relays/kills and such except the rectifier with those of a known running bike.

[TopCatGr58]

Hey Bobber,

No...I'm not the man....I think I was brain farting very badly last night! I'm surprised someone didn't jump all over my reply!!

The gray and orange wires are the trigger wires for the coils, they are controlled by the TCI switching them on/off....closed/open circuit which causes the coils to develop their magnetic field, and then allowing it to collapse which generates the high voltage surge to the spark plugs!

The Orange and Gray wires should not show voltage when they are disconnected from the coils. The power TO the coils is provided by the red/white wire(s). These are the wires(red or red/white) that connect to the TCI that send OUT the voltage to the ballast resistor circuit as well as directly to the coils. The Orange and Gray wires that are coming back from the coils are the (-) side, and should NOT have any significant voltage reading UNLESS they are connected to the coils, then they would/should be 12 volts minus the effect of ~2.5 ohms of the primary resistance windings of the coils, which would be about 9-10 volts...what you have found on your GRAY wire....again ONLY if it's connected to the harness.

SO...the very low voltage of the Orange can be diagnostic....but first you need to check the red/white wire at the COIL to see what voltage you have there.....for EACH coil, making sure you have ~12 volts going INTO the coils.

IF you do, and you're not seeing much coming out of the Orange wire when it's connected to the coil, then you need to check the primary resistance of the coil for the Orange wire...you may find that it's much more than 2.5 ohms since it's possibly choking the current coming into it via the red/white wire!?!?

Phew, I hope I haven't caused you to waste too much time doing possibly unneeded troubleshooting??
T.C.

[xs11bobber]

God bleep f-bleep-ing bleep da-bleep piece of s-bleep

It's not a waist if you're still learning. I'm not mad about it, lol. Sorry for the delayed reply. Had a college friend doing some remodeling he needed help with near North Manchester, so I just stayed there for a couple days while helping out.

Red/white at the coils, plugged in, w/key on was getting 10.05V. This is not enough? (it is about 48°)

Coils unplugged(primary resistance) tests varried a little. I checked them both twice and red/white and grey was 2.4/2.5. Red/white to orange was 4.5/2.5.

you may find that it's much more than 2.5 ohms since it's possibly choking the current coming into it via the red/white wire!?!?

What does that mean since it looks like that is happening?
I did notice the incoming red/white has the double bullet connector (the one that looks like an oversized female spade) and finigled with it a bit and noticed it was very loose. I recall seeing a slight spark there once w/key on as well. Squeezed the plug a little with some pliers. Now a 10.63V @ red/white.

Still getting 10.5V on grey and 36.5MV on orange.
I got 10.35V on the red/white on the coil with the orange. Now the voltage setting on my DMM is acting WAY up so I don't know how true the following tests will be until I can return this POS to Sears and get another one. It's always something...

...10 minutes later...

...Well, I thought I might be able to take a neutral like reading and just subtract what it started at, but that's not gonna work when it says there is 1.63A in AIR! Then when you put juice to the DMM it says overload

What can be diagnosed from my bike tests? I think I got the DMM figured out

[TopCatGr58]

Hey again,

Okay, from what you've posted, it seems like your PNM coil that's connected to the Orange wire is SUSPECT! Regrettably, a few folks have reported problems with their PNM coils failing! I've still got mine, and they are still working flawlessly. A few folks tried SOLDERING connectors to them, and I thought I remember a warning about NOT soldering connectors, because it can cause the wires on the inside of the coils to come loose!? Mine are slipon/crimp on only.

The 10.63 volts at the coils still bothers me. Bypassing the ballast resistor, along with just turning the KEY on, should have the TCI sending the full 12 volts of the battery directly to the red/white wires at the coils. Once it gets running, because of bypassing the ballast, the voltage should remain at the 12 volt level, and not drop to the 9 that it would IF it were going thru a ballast resistor. Not getting but Millivolts out of the Orange wire when it's plugged into the coil also indicates a possibly break in the primary wires, and seeing variable resistances...4.5/2.5 doesn't sound good/right either.

You can use an OEM coil on that side for a short time without worrying about damaging the coil when running...like 10-15 minutes or so, that way you can see if you can get the bike to run and fire on all 4, if so, then that'll pretty much confirm that the PNM coil has gone bad! Just double check the connections of the plug set you put on the coil to make sure it's properly connected, retest the resistances, and if you still get the same faulty readings, then you can probably get rid of that coil, unless you want to try taking it apart to inspect the connections on the inside...in case you may have originally soldered the wires to the connectors instead of using slip on connectors!?

You might also want to follow the Red/White wires thru the harness, checking at each connector to see what voltage you get till you find the almost full 12 volts that it should be putting out, then re-clean the connectors you went thru trying to obtain/maintain the 12 volts as you go back towards the coils.
T.C.

[xs11bobber]

I recently discovered O'Rieleys (my new favorite parts store) and happened to stop by there getting some brakes for a VW. I picked up a new DMM and a few weather proof gold plated bullet connectors. I will re-run all tests again later today to be sure of my problem and report my findings. Thanks for all your help TC.

[xs11bobber]

It's been hectic with winter practically skipping fall in the area. Leaves and trees and flat tires, oh my! haha

OK. With my new DMM...

I have 2.4/2.5 ohms of resistance on each coil. It alternates.

I have 11.72V on the Red/White at the coils w/ key on and my battery tested at 12.43V. So that sounds good.

Volatge on the Coils:

• Left Coil - 9.54V IN and 33MV OUT
  Right Coil - 9.76V IN and 9.87V OUT

So I have a bad NEW coil?