81 SH (?) coils different (?)

[Mike Hart]

Originally posted by oldnortonrider


YES; on one coil >>, the one on the right, feeds the middle two
cylinders.
SEZ : USE WITH EXTERNAL RESISTANCE .

That would be a 78-80 coil. 81 and up had no ballast resistor. Is the other one smaller?

I'm confused now about which coils are in your bike and which are spares~!

The ones in your bike - do you see the part #'s on them?

[oldnortonrider]

Yes, the one on left side , feeding #1 & #4 > is smaller, with one sparkplug wire on one side of the coil, not going as far in the housing as the other; like in the "repair" thread.
Ain't got "spares", unless yer referring to the coils on my 79Standard, that's settin' . I think I remember, both the coils on it, are comparable, ie.look-the-same, as the one on 81Special ,rightside, that's feeding #2 & #3 >> that we're trying to figure out, if it came on my machine original.

[Mike Hart]

Okay, now I see. Your rh side coil is from a 78-80 bike, the one that says Use External Resistance. Well, nothin' fried, so I guess you're ok

[oldnortonrider]

Originally posted by Mike Hart
Okay, now I see. Your rh side coil is from a 78-80 bike, the one that says Use External Resistance. Well, nothin' fried, so I guess you're ok

......no, "not, 'ok' " ; for anybody else, that ever does this swap, without the ballast resistor. "OK" , for me, now; but I had a couple years of mysterious "ignition/sparking" problems, before I figured out what was causing the problem , and what worked to fix it, without a ballast resistor !
Originally, when I got it, it had "R" sparkplugs, all 4 cylinders; ran alright. Manuals call "for no 'R' s" on the NGKs. So, eventually, I put new plugs: no "R" all the way across. When it would warm up, the middle 2 cylinders would quit; no fire. When it'd cool back down, it'd run alright.......>like a circuit breaker had kicked off; wait awhile; comes alive again. Well I knew my ignition setup, didn't have a circuit breaker; but I got to wondering , before I decided to swap out the coil >> if the goofy coil wuz sorta acting like a circuit breaker, and if so, why wuz it? THEN , I spotted that bit on the housing:USE WITH EXTERNAL RESISTANCE .
This puzzled me for a bit, cuz it wasn't on the other coil.
I putB]R[/B] plugs in the middle cylinders; "R" for "RESISTANCE".
(AS I wuz doin' it, I thot, this couldn't possibly work, but we gotta
try !??)
It ain't missed a lick since!

[Bill]

J Carlton Riggs (oldnortonrider) wrote:

the one on left side , feeding #1 & #4 is smaller, with one sparkplug wire on one side of the coil, not going as far in the housing as the other; like in the "repair" thread.

The coils on my old '81 SH were the same size and configuration. Both were the smaller size coil with one of the high tension wire tunnels shorter. All three '79Fs I've had were the larger style with both wire tunnels the same. FWIW...

[oldnortonrider]

Am attaching this posting regarding current "electrical adventure", to this earlier thread, that must be connected to "my current situation".

5-6 days ago, after my machine having been parked for 2 days, I go to get on it, to start it, and head out. Wouldn't start. Had run in fine, when I'd parked it, and had been running fine for last several months. Checked a few things; NO SPARK ON ALL FOUR!
Got all tools out, and set up to do some serious checking, after determined the fuses were all good, and kill switch not the problem. At this point, I need to mention, that there is a thread, 4-5-6 months back, where I had discovered that PO had changed the 4R0 TCI to a 2H7 TCI, and had changed timing plate that had old type advance; and as shown on earlier part of this thread~~had swapped in a one and half ohm coil on right hand side that runs the inside two cylinders (No's 2 & 3). And no ballast resistor to help that coil along. Been running alright. 38,000 miles on this "setup", since I'd gotten it 14 years ago. About a month ago, I had decided, because of the mileage increase and other advantages stated in TopCat's pictorial, that I would order MikesXS coils and install. Hadn't put 'em on yet.

Back to the "NO FIRE" dilemma. I work slow; trying to learn as I go (and remember what I've learned). Tank off, seat off. With the multi-meter(s) [I've got the digital and analog, both], I check everything, that could have to do with losing fire ON FOUR. Failed to mention, that "yes", everything lights up fine with ignition key on; battery up 12 volts plus. Dealer's manual shows the tests to check for on TCI with multimeter. Clymer's manual doesn't. I do those checks and come up with only one discrepancy. Black wire, according to the book is supposed to have ZERO ohms; I'm getting 6.4 ohms. OK; I've got a spare TCI 18 miles from here in my storage unit. I bum a ride, and go get the (2H7) TCI. When I get back to the motorcycle, before I swap out the TCIs.........just for the heck of it, I decide to check secondary wires (spark plug wires) of the two coils. Telling myself "waste of time~~both coils couldn't quit at same time". Checked 'em anyhow~~!!~~left hand coil is showing "27,700" ohms resistance; book sez 15,000. Right hand coil gives NO READING of any kind. nothing.

OK, tomorrow I will begin to install the two new "MikesXS" coils, which I'm "guessing" should put me back to running again. And, I'm expecting and hoping, that all will be well again, without changing the TCIs. "The '6.4 ohm' reading" at the black wire at TCI~~I'm thinking that "might" be related to one or both coils being faulty. I'll recheck it and if it still read that way, I'll plug in the other TCI and see if I can get proper reading.

I guess what I'm somewhat concerned about ...............I don't want something else, that I've not discovered to mess up the two new coils.

[TopCatGr58]

Hey Carlton,

The MikesXS Coils don't need/use the ballast resistor, so as long as you're getting 12 volts on the (+) red/white wire, then that's what they need.

Your readings on the one coil WITH the plug caps ON is about right...the caps have ~5-8kohms EACH which is added to the COIL ALONE value of 15K, and you get the 25-27Kohm range. It's the OTHER coil with NO readings that would be the concern, but you need to pull off the caps, inspect the coil wires for corrosion, and retest the ohms with just the bare plug wires. But IF it was running the 1.5 ohm coils without the Ballast resistor, then it may have finally gotten fried!? Again, no worries with the MikesXS, they use the full system 12 volts which should be there when the Ballast Resistor is bypassed!

With a loss of spark on all 4, I would suspect the TCI, or the PU coil/wires, but can also be due to too LOW voltage going to the TCI. Full battery may not necessarily provide the full ~10.5 volts the TCI needs, IF there is considerable corrosion, etc.!
Good Luck troubleshooting!
T.C.

[oldnortonrider]

Randy, or 3Phase, or~~somebody...........I need some input, as to what that "6.4 ohm" reading on the black ground wire of TCI, would be an indication of................(??)

TopCat; appreciate you "straightening out" my thinking on that LH coil secondary wire(s) reading. Those other readings that are shown, in dealers manual, that are tests to do to all the TCI wire plug-ins, are reading what they're supposed to read on my multi-meter, except the black wire. The connections that are supposed to read "12 volts", are showing the same, as a direct test at the battery. Not losing anything between the battery and TCI.

[randy]

oldnortonrider;

My best guess would be that the black wire has a bad connection to the frame. IIRC, that ground lead gets tied down to the frame at the regulator.

[oldnortonrider]

Randy; thanks~~I'll check that. I didn't know where to start looking. I'll clean up some other grounds, also.

[oldnortonrider]

Spark.

Started checking for "what grounds" to take apart and clean up.

ONE MORE TIME~~I said to myself "check the black ground wire on TCI"............one more time. Checked it. IT READ ZERO! ~~ like it's supposed to read. So I sez to myself~~"then that means I've got spark on at least two of the plugs; I've got one good coil on here, the way it has tested". Checked #1; GOOD SPARK. Actually, it tried to start~~with the other secondary wires on the other 3 cylinders. Gas tank off. Yep, I've moved something~~wiggled something. TopCat, get this~~that rh coil that feeds #2 and #3; cannot get a reading on the multimeter on secondary wires, but it will spark the plugs when turned over!
Gad. I'll start getting these new "MikesXS" coils ready to install with the Accel wires that I have.

No, I don't for one minute think it is "fixed"~~but I'm moving in that direction.

[3Phase]

Originally posted by oldnortonrider
Randy, or 3Phase, or~~somebody...........I need some input, as to what that "6.4 ohm" reading on the black ground wire of TCI, would be an indication of................(??)

Resistance between the TCI ground wire and ground can be your multimeter probe having trouble 'punching' through dirt/corrosion to good metal underneath and giving a bad or intermittant reading.

It can be a bad solder connection in the wiring harness where the TCI ground (Black wire) connects to the heavier-gauge Black wire for the system ground.

It can be a broken wire at one of the connectors or inside the wiring harness.

It can be a loose/corroded connection where the two Black wire connectors are grounded at the Regulator/Rectifier with one of the mounting screws.


You've said the '81 schematic is similar to the '80. If so, the TCI is grounded through the system ground at the Regulator/Rectifier.

To check the ground circuit from the TCI to the ground at the Regulator/Rectifier, unplug the TCI and remove the ground connectors from the Regulator/Rectifier.

Measure the resistance between the Black wire at the TCI and the ground connectors at the Regulator/Rectifier. One of the connectors should measure 0 Ohms.

Reconnect the ground connectors to the Regulator/Rectifier and measure the resistance from the TCI Black wire to ground. Again, it should be 0 Ohms.

TopCat; appreciate you "straightening out" my thinking on that LH coil secondary wire(s) reading. Those other readings that are shown, in dealers manual, that are tests to do to all the TCI wire plug-ins, are reading what they're supposed to read on my multi-meter, except the black wire. The connections that are supposed to read "12 volts", are showing the same, as a direct test at the battery. Not losing anything between the battery and TCI.

You should install those new coils you bought. Right now it looks like you're running one coil that's supposed to have a ballast resistor in the primary circuit and one coil that is not supposed to have a ballast resistor in the primary circuit.

Other than a very rough indication of the primary/secondary winding ratios and input/output voltages, the secondary resistance - including resistor plugs, wires and resistor spark plug caps - has very little to do with the primary resistance. Unless the coil is shorted internally the primary and secondary sides of the coil are physically separated from one another.

Any coil that's supposed to be used with an external ballast resistor will draw too much current without the resistor. Drawing too much current will make the coil overheat, misfire, and eventually burn up the coil.

Old-style Kettering (mechanical breaker points) ignition systems will overheat, misfire, and eventually burn up the ignition coil/s and the breaker points.

The newer TCI systems will overheat, misfire, and eventually burn up the ignition coil/s and the breaker transistors.


Have fun, and don't let this electrical stuff get you down!


Regards,

Scott

[oldnortonrider]

I have attached new 8mm Accel secondary wires to the new MikesXS coils. On one set of plug wires I re-attached the black Denso plug caps from the old coil. On the other new coil, I attached the rubber Accel plugs, because I couldn't get a reading with the caps from the old coil. Couldn't get a reading with those caps when they were on the old coil, either. The wires with the rubber Accel plugs on the new coil give me a reading of 28.3Kohms. The other reading has me confused. The wires are about 4 inches longer, each, than the wires I've got on the other coil with the Accel plug caps, and have the black Denso caps that had been on the old coil's secondary wires. These longer wires with the black caps are giving me a reading of 62Kohms. (?? )

3Phase; that's good stuff in the above post, and I appreciate the effort you put into it. Tomorrow, I'll put most of it to the task.

[oldnortonrider]

Success.

Been working on it everyday, since last posting. Sometimes would have fire (depending on the phase of the moon); and, sometimes it wouldn't have fire. Got into everything, except opening up wiring harness.

Finally, bummed a ride to "O'Reilly's ", and got a spade fuse panel. Installed it. The old fuse panel had a bad connect at one of the end clips that held the glass fuse to headlite. Was fried, and mostly burnt through, but not visible while still on the machine.

Goes good now; no intermittent firing, at all. The new "Mike'sXS" coils, with the YELLOW Accel wires , are good to look at. Can't see the coils, but I know what's at the other end of those yeller wires........................

[oldnortonrider]

I would like to add a GREAT BIG THANK YOU; to "3Phase" for his excellent color schematic that one can find on the "On Any Sunday............." thread, that you still have to click your way to get at (here) http://home.att.net/~phase3/XS11/XS11G_US.GIF

I would suggest to XSers that would like to make their future "difficult" do-it-yourself electrical repairs "not so difficult", and the mysterious non-findable electrical gremlin~~findable; to download 3Phase's schematic and learn how to pull it up in Windows Paint , if you don't already know how. I had never used Paint's File Menu to drop down and "Open....." a download before. Wow; whole new world in front of me.

I have the dealer's XS11 manual ($60.00), that I've had for about 10 years; the schematic(s) are in black and white (pitiful). I have the Clymer's manual (color schematics); the fuses are not labeled to tell you which colored wire runs what.

Tracing my electrical problem(s) had been further exacerbated by the PO having put an aftermarket THREE FUSE box on, that had all different colored wires from each side of the fuse panel for about 5 inches, and then were spliced into the wire they went to and profusely wrapped and taped, so that it was a full time guessing game. He had the signal wires separately snaked in and under the seat and had the old style metal cylinder type fuse that one would use on a car or truck that plugged into the car/truck fuse block, plugged into terminals at the ends of the wires~~this instead of "the fourth" fuse called for on an original XS fuse panel.

For years, I've been wanting to become expert with a good multimeter; and for years, I've been wanting to not have great fear of an electrical gremlin ruining my world on a trip, where I'm a thousand miles from home. Especially, since most of my trips are alone. I feel like I've made some real headway this month.

3Phase~~I notice you have a California address; I was born in Long Beach~~raised up there........................................