Boyer Ignition Troubleshooting

More basic Boyer Bransden Troubleshooting

[@rickbaker1912]

Hi, watched your video last night to gain a greater understanding as I have no spark. Using it as a method for fault finding discovered a trigger wire had become loosened in a bullet connector. Pushed it home firmly and now all's well. Many thanks.

[@heinvastenouw]

My 1974 Triumph Trident T150V has a newly installed Boyer Brandsden ignition (type Mark 4). After a successful installation the engine ran fine but after a while it became very difficult to start. When it fired up, after many kicks, the engine ran horrible. I checked the plugs for a spark: that was OK, so all my attention went to the carburettors. After many hours of checking, cleaning and justification nothing was found to be wrong so I went back to the ignition. I found your youtube movie about the test of the Boyer ignition. My test showed that the coils had power allways, in the contrary to what you showed in your test. That could not be a reason for malfuction of the engine but as you noted: when the engine does not run and contact is on, there should not be power on the coils. I checked the pickup coil with a magneto just like you did, which created sparks at the plugs. Check for timing was positive, so overall there seemed nothing to be wrong. With no idea left where to look, I decided to read the specs of Boyer Bransden once more. They stated that electromagnetic interference could occur if you deviate from their spec for the HT cable, plug caps and spark plugs. The right cable has a copper core (mine had carbon), the plugcap is recommended to be of the suppressed type with 5000 ohm resistance (mine had none) and the plug should be non suppressed (mine was of the resistor type, so suppressed). I made three new cables and installed the right spark plugs. Result: one kick and engine was running very stable at idle speed and cold engine. This was the right solution. This issue of electromagnetic interference is easy to overlook, however it might cause serious trouble. How to test this? I have no idea. I think you have to comply with the specs in the first place, that is probably the best way to go.

[@saywhatsaywhat1]

This is something Boyer fails to emphasize, the 5K ohm resistor caps or resistor wires are essential or some odd problems (like yours) will occur.

[@heinvastenouw]

Very helpful, appreciate your contribution. Will use these tests to verify the ignition of my T150V

[@saywhatsaywhat1]

Let me know what you come up with, it's a pretty simple system overall.

[@richytill]

Thank you

[@sargas3]

Very good video. I'm new to Triumphs and im really happy for people like you that put this info out there. I did the same test because I have no spark. however my test light comes on with out me turning the motor over. All coil connections are lighting and do not go down. Do you have any advise?

[@saywhatsaywhat1]

Sounds like a short to ground in the primary, check your wiring. Coils are probably getting pretty hot so don't leave it on for too long.

[@michaelbrind9222]

The bsa A65 twin I'm working on that has a wassell fitted seems to have an intermitant spark issue works fine cranking over 5 or six times then no spark for a bit then spark comes back.

[@saywhatsaywhat1]

I would check your connections for voltage drop due to a loose crimp or corrosion and of course all grounds. Also make sure you have 5K resistor plug caps otherwise you get some funny symptoms especially on BSA's for some reason.

[@heinvastenouw]

My 1974 Trident T150V started with a kick, however when riding my bike, I noticed that I was loosing sparks. There was too much unusual but light vibration coming from the engine. Electronic ignition is more sensitive to voltage drops than the old fasion points type ignition. When there is an irregular power input, electronic ignition will malfunction. I decided to check the power of the Boyer ignition. I put an oscilloscope at the power cable of the ignition and I found the following: - The standard single fuse vibrates so much in its fuse holder due to engine vibrations that the power may vary some volts over time. This looks odd, but I could clearly see this on my oscilloscope screen. I changed the fuse and fuse holder to a modern type, that is not sensible to vibrations. - The wiring from the battery to the boyer ignition unit goes a long way in my bike. The wiring, switches and connectors are about 50 years old now and I noticed that the resistance from the battery to the boyer unit was sensitive to vibrations also. I bypassed the original wiring and made a direct connection between the battery and the boyer unit. (With this I bypassed the kill switch, but that’s ok for me) Both measures had success. The engine ran fine afterwards.

[@daveco1270]

Where was the test light wire alligator clamp hooked up when you did this test? Can I just clamp it to the frame for ground?

[@saywhatsaywhat1]

Sorry for the delay, yes a good ground on the frame itself

[@davethomas6136]

how do you test the black box , to see if it ok, i see you touched the black/yellow wire and black/white together , but i didnt see if it sparked or not when you did this,

[@saywhatsaywhat1]

Go to the Boyer 101 video @ approx 3:30 and you can see the plugs sparking when you cross the black/ yellow and black/white wires.

[@sherrybcampbell943]

Does this set up not require a battery. L dont see a battery hooked up. Im running a 69 750 Norton customized with nowhere to put a battery.