T140 Wiring

Sorry Honker, no where near you, but have totally rewired a few of them. Maybe one of us can help you through it on here.

Wiring is always an arse but if you take your time, draw or write things down, you can slowly work your way through it.

 

Honker
What year T140 is it. And what's fitted like boyer and bits or standard. Really does need to be asked as it all affects the wiring. And is it positive or negative earth. But i have had so much help from this forum in the past. Also look at the wiring as i have had a couple and had to dump the loom and start again. Some people out there think they can just start cutting and splicing wires all over the place then hand the bodges on to us.
Joe.

 

Honker
Those switch's can be dodgy. Open them up and make sure they have not corroded. But be careful as they have a copper plate and behind a ball bearing and small spring. Can't remember how many I have lost over the years. What I have done over the years is bridge the points in the switch to see if it operates the lights. And the ignition switch can play up as well. Only good thing is the wiring is in the head lamp and sometimes you need to run a separate earth from loom to head lamp to make it gel better.
Joe.

 

Have a look here, maybe this geezer was having your problems

https://www.triumphtalk.com/threads/bonneville-t140-1976-electrical-wiring.53436/

Older Triumphs are pretty simple beasts, the existing cobbled/messed with harnesses or new harnesses are either wrong, the manuals are wrong (particularly for later 70s bikes) or they are just too difficult to figure out. These days I always bin the lot and just rewire the whole thing with brand new electrical gear.
I use the fewest proper bullet and ring connectors (soldered onto the wire) as I can get away with, use 3 way Harley ignition switches (cause they work and so I can turn the lights on when I want them on) and hard solder everything else. Use new switches for lights, horn and signals, get the hydraulic switches for the brake lines and renew stator, solid state rectifier, coils and use the Wassell electronic ignition. I bin the rev counter and drive (as I already know when to change gear) and am moving to electronic speedos that actually tell the speed cause they use sensors put on the front wheel rather than some antiquated geared drive thingy that may be the wrong ratio or wrong way round.

I understand, however, getting a vintage bike back to it's former glory, the closer to standard you can get, the better it should be as that's how it was designed (and those designers forgot more than I know) to be. And those of you that can do it, more power to your elbows.

Good luck Honker. Bish the Bosh, use the Force, this is the Way. I think I need a lay down

 

Honker
This is also something I have found and is groggy in my mind now. But some time when you get a cowboy on the wiring. On that electronic they use I think it is a brown or brown and white wire and that supplies power to the right switch gear. But check it out as its been a long time and I may have got mixed up.
Joe