Engine kills - Electrical gremlin

[mrdigitech]

It has been a very long time since I've posted on this forum. I attended a color run a couple years ago, and would love to again if possible... Anyways my latest issue:

Riding along fine got about 10 miles from home.... then everything cuts out suddenly, engine dies and all lights are off. Pull over to, put on kickstand and bike starts right up. Put it up straight and it kills. Put back on kickstand and bike starts right up and runs fine. Put is straight up and it kills.

Only thing that has changed this season is I put in a new maint free battery.

After the above happened I eventually got it home (It just suddenly kept running long enough to get home). I checked my wires and fuses and all seem to be as they were (not in pristine condition, well... because she is 35 years old). A few years ago I did do the fuse box mod/upgrade and haven't had issues.

Took her out on another short run, probably 30 miles and all seemed fine. So I pack up for a trip to the north shore (180+ miles round trip). Got there fine on 2.5 gallons approx. Stopped to fill gas and then suddenly it would not start. I got power, neutral and oil lights came on but nothing would happen when I hit the start button. Rolled her away from the pumps and gave her a 10 minute rest while I myself had a cold one. Hit the start button and she started right up. Put her up straight and it killed. I probably repeated this for the next 30 minutes. Start fine and run fine on kickstand but kill as soon as I put her up straight.

A fine gentleman from the local garage came out and said there is a safety switch that is sending the kill signal. With him standing there the very next time I try. Started fine on kickstand, tipped up straight and she kept running fine so I hit the road back home. She killed on me 5 times on my way home.

Can someone point me in the right direction if its possible with my description?

I read another post about a clutch switch starter relay bypass within the headlight wiring? Could this be my issue and if so can someone elaborate on how to do this bypass?

Any suggestions are greatly appriciated

Cheers!

[James England]

The tip switch is on the frame crossmember under the fuel tank. It sits in two metal prongs in a rubber casing and has the word "up" written on it. As far as I understand it, the tip switch only cuts off the ignition circuit and does not include the lights. However, to eliminate it from your enquiries, just bypass it by disconnecting the bullet connectors which feed it...there are only two of them, and join them together......on the wiring harness side of things, of course!

The switch is just visible in this pic, at the very bottom...a black square in the middle of the frame crossmember

[jetmechmarty]

In this image, it's item #10.



Without looking at the wiring print, you might be able to run with it unplugged. Or...you may have to jumper it or short past it. Somebody who has done this will chime in, I'm sure.

[James England]

In this image, it's item #10.



Without looking at the wiring print, you might be able to run with it unplugged. Or...you may have to jumper it or short past it. Somebody who has done this will chime in, I'm sure.

ding ding. Just chimed

[mrdigitech]

no dice

Thanks for the quick responses.

So I found the switch. Mine is labeled "upper". When i tip it from side to side I can hear the switch inside.

I disconnected it and jumped it on the harness side. The bike would not start. Turned over and over and over, etc. Tried many times gas is flowing but seems like I have no spark now...

Plugged it back in and the bike started right up. Turned it off. Now it will not start again. I have lights but nothing happens when I hit the start button. Gremlin must be elsewhere. Thanks for the info. I hate electrical.

[James England]

Try disconnecting the switch but NOT jumping it on the harness side.....

[mrdigitech]

and...

I began looking elsewhere

Started looking around the battery at wires and when I was twisting the harness around to inspect the black tape just pealed away in my hand. So I inspected further pealing more away. I did not find anything broken or burnt. Thought I'd see if it would turn over. Sure enough it did, started right up and ran, tip it up right and it kept running. I shook the harness where I had pealed away the black tape and it killed, and would not turn over. Shook it some more and it started right up. So i guess my problem is in there somewhere?!... Possibly both!?

One thing of note possibly is that my seat pan is terribly rusted, I mean terribly. I could probably fold it in half without breaking anything... Probably sitting on wires under there...

Tomorrow I'm going to start tearing into it further checking every connection....

I'd rather turn wrenches than mess with wires

Thanks again for your replies.

[Brent]

connections

I had a similar problem and missed the plug hiding under the air intake snorkle. It is on the main fuse (left side) circuit. Everything was dead and I was at barber motorsports park. One 30 year old plug missed cleaning and Everything quit... XSive friends and riding buddies got it sorted out quickly and I had a good weekend at Vintage days, & good ride home.

Good luck wrenching

I began looking elsewhere

Started looking around the battery at wires and when I was twisting the harness around to inspect the black tape just pealed away in my hand. So I inspected further pealing more away. I did not find anything broken or burnt. Thought I'd see if it would turn over. Sure enough it did, started right up and ran, tip it up right and it kept running. I shook the harness where I had pealed away the black tape and it killed, and would not turn over. Shook it some more and it started right up. So i guess my problem is in there somewhere?!... Possibly both!?

One thing of note possibly is that my seat pan is terribly rusted, I mean terribly. I could probably fold it in half without breaking anything... Probably sitting on wires under there...

Tomorrow I'm going to start tearing into it further checking every connection....

I'd rather turn wrenches than mess with wires

Thanks again for your replies.

[James England]

I'd invest in a tin of De-Oxit spray. Then treat every block connector on the entire bike. There are blocks behind the battery frame, behind the fuse box mount. With an old wiring harness, it's usually corrosion at the blocks themselves that causes problems. I always use de-Oxit as it's brilliant. One tin will do one bike, I've found.

[D0wn5h1ft]

Theses problems are sort of hard to track down if you're not that familiar with electrical circuits. The key is really to identify what should be happening and compare that to what is happening.

You mention that the bike won't start but it will turn over. That means it's likely a short somewhere in your ignition circuit. So, first place I would check is the voltage at your coils. You can do this by probing across the primary coil and if you have stock coils it should read 6v. If you get 0v that means you have no voltage to your primary and thus no spark. If you have power at your primary and still no spark then it's an issue with your electronic ignition and that's another rabbit hole.

HOWEVER, it sounds like you just have a short in your wiring harness somewhere that's present only when you put pressure on that part of it or it is moved a certain way. I've had numerous ones myself and the only way to find it is a good visual inspection along the length of the wiring harness. You're looking for places where a friction point may have rubbed through the insulation and is exposing bare wire thus causing a line-to-line fault (two bare wires touching) or a line-to-ground fault (a bare wire touching the frame). This is exactly what happened to me earlier this year. My aftermarket seat had been making contact with my wiring harness and had pinched it between the seat and the frame. At first the bike ran great, but over time the seat rubbed through all the insulation and shorted wires to the frame. When I would sit on the bike it wouldn't start but when I got up off the seat it'd fire up just fine. Crazy right?

Take a good look at all of it before you start probing all over the place trying to find the issue because probably like me you'll just get a bunch of weird and inconsistent results due to the issue being intermittent.

Remember, one mechanical problem and a machine may still run but a single electrical fault brings down the whole system! Source: a few years now as an electrical engineer

[MarkD]

Have a buddy whose Triumph kept dying, so here's what he did: in the dark garage, he keyed the ignition to ''on'', then turned the handlebars from side to side. He noticed a spark along the wiring harness near the fork headstock. Maybe it's worth a try?