Boyer mystery

[seattle##gs]

I have a Boyer which refuses to fire by kicking it over. I've wired in several dozen before.
The battery reads 12.35.
By unplugging the leads at the stator and tapping them together it will fire with a good single spark every time. Not the shower of sparks from a bad boyer.
I can also trigger it by disconnecting one lead at the stator and reinserting it. The leads are connected to the proper one to the black box.
I have replaced the stator and the rotor and no change.
Kicking it over produces NO spark. What gives?

 

[cliffa]

I have a Boyer which refuses to fire by kicking it over. I've wired in several dozen before.
The battery reads 12.35.
By unplugging the leads at the stator and tapping them together it will fire with a good single spark every time. Not the shower of sparks from a bad boyer.
I can also trigger it by disconnecting one lead at the stator and reinserting it. The leads are connected to the proper one to the black box.
I have replaced the stator and the rotor and no change.
Kicking it over produces NO spark. What gives?

On the Boyer site, there is mention of making a shim out of a can, and wrapping it around the taper to bring the rotor out closer to the pickup. Also worth checking the continuity through the two coils. I think it should be 132 ohms. Is it a new device? If not also try wiggling the wires and watch the meter..

 

[cliffa]

Looks like you had a similar problem a few years back…. https://www.accessnorton.com/NortonCommando/boyer-magnets.36615/#post-612460

 

[baz]

I have a Boyer which refuses to fire by kicking it over. I've wired in several dozen before.
The battery reads 12.35.
By unplugging the leads at the stator and tapping them together it will fire with a good single spark every time. Not the shower of sparks from a bad boyer.
I can also trigger it by disconnecting one lead at the stator and reinserting it. The leads are connected to the proper one to the black box.
I have replaced the stator and the rotor and no change.
Kicking it over produces NO spark. What gives?

You haven't accidentally wired the polarity wrong have you?
That'll give the symptoms you described

 

[hhh]

I recently had a similar problem: the Boyer would function normally anywhere from about 2 to 20 minutes, and then it would just die while riding like someone turned off the ignition switch. In 10-20 minutes it would work again. During the non-working time, it would spark only on power cycling but not by kicking or touching the stator wires together. Replacement of the box was the cure. It's likely some kind of heat failure that heals itself with time until the next time and is very repeatable. The weirdest part is that I ran the bike regularly for two years and this problem started after a year of non-use.

 

[Tornado]

For testing the coils on stator, just pass a magnet near them with power on. It should fool the ei to think the rotor is triggering the coils. If this does not work then suspect fault in the coils.

 

[hhh]

For testing the coils on stator, just pass a magnet near them with power on. It should fool the ei to think the rotor is triggering the coils. If this does not work then suspect fault in the coils.

On Commandos especially due to the isolastics, the points wire itself can fail due to work hardening and internal breakage, or near where the stator wires are soldered to the stator those can fail. These can be very insidious to troubleshoot. Attaching clips to the stator wires at the box and vigorously wiggling the wires will usually reveal it. In my case it passed these tests with flying colours and a steady 140 ohms, but I've had both these issues in the past.

 

[o0norton0o]

Eric, I have 2 extra black boxes (old analog boyers) from when I changed to the microdigital red box version. If you want to borrow one to use as a substitute you can drive out my way and pick up a whole set, with the magnetic rotor, coil pick up plate and black box. It will allow you to test each part by substitution... which is probably always the best way to test electronics except that it usually costs money to buy extra parts to use as a substitutes. However, in this case you just need to spend the gas money to drive east 22 miles....

 

[hhh]

Did you notice a significant difference going from analog to digital? I would expect an improvement in low-end and mid-range torque since the advance curve can be optimized.

 

[seattle##gs]

Eric, I have 2 extra black boxes (old analog boyers) from when I changed to the microdigital red box version. If you want to borrow one to use as a substitute you can drive out my way and pick up a whole set, with the magnetic rotor, coil pick up plate and black box. It will allow you to test each part by substitution... which is probably always the best way to test electronics except that it usually costs money to buy extra parts to use as a substitutes. However, in this case you just need to spend the gas money to drive east 22 miles....

Thanks but I have a few extra boxes and stators and rotors. I've already substituted the rotor and stator one at a time so now onward to the box. Thanks for the offer.
A few months ago I was struggling with a new boyer and discovered that it would spark if I tapped the wires at the stator with my finger.

 

[o0norton0o]

Did you notice a significant difference going from analog to digital? I would expect an improvement in low-end and mid-range torque since the advance curve can be optimized.

Supposedly, it makes the bike idle better and not kick back when you try to start the bike. I'm on my 4th hematoma on the back of my right leg in the last 2 years. I'm getting pretty tired of it. I emailed Boyer to ask them what the timing is at kick over speeds and they said that it's retarded 40 degrees at start up, so that would be 9 degrees past TDC IF the proper voltage is going to the box. From what they said, there's no way it should kick back unless there's a low voltage situation. I actually leave my bike on a battery tender when it's parked, so it should have a good surface charge. I can't go on like this. My leg is still visibly swollen and blood stained all the way down to my toes.... Sorry, I digress....

I do think the idle stabilization helps, but you have to get the carbs right too, so it's not a single variable situation. I think the microdigital is good, but the analog was good too. It's hard to remember if there was much difference, since it's been at least 20 years that I've been running the red box instead of the black..

 

[hhh]

Thanks for the detailed reply. I know on my singles going from points to analog is a noticeable loss of torque in the lower revs. I actually prefer points on them. Also, I have the same problem of vicious kick backs. I usually have some state of injury on my calf from them. When I tried to retard the analog, the top end range suffered, and I like my top end, so I live with the kick backs. I've since learned to kick off the bike which helps, but a Norton's stand probably isn't up to that, not to mention it can cause the bike to fall on top of you from the compression keeling it over towards you.

 

[baz]

Thanks for the detailed reply. I know on my singles going from points to analog is a noticeable loss of torque in the lower revs. I actually prefer points on them. Also, I have the same problem of vicious kick backs. I usually have some state of injury on my calf from them. When I tried to retard the analog, the top end range suffered, and I like my top end, so I live with the kick backs. I've since learned to kick off the bike which helps, but a Norton's stand probably isn't up to that, not to mention it can cause the bike to fall on top of you from the compression keeling it over towards you.

On the advice of kommando I fitted a cut out button to my BSA b50 fitted with Boyer ignition
So I could switch the power to the ignition on once I'd got the engine past tdc and into the kick-starting position without the ignition thinking the engine is running and advancing

 

[hhh]

On the advice of kommando I fitted a cut out button to my BSA b50 fitted with Boyer ignition
So I could switch the power to the ignition on once I'd got the engine past tdc and into the kick-starting position without the ignition thinking the engine is running and advancing

Are you saying you start kicking and then turn on the ignition mid stroke?

 

[DennisMo]

I installed a Tri Spark and it calculates the speed of the engine and at under (I forget but I think 500 rpm), the spark is ATDC.

I replaced my Boyer with the Tri Spark and without touching the carbs, my bike now idles well when cold and never stalls cold like it did before. It always stalled cold with the Boyer.
Dennis

 

[seattle##gs]

I put a Tri Spark in the Atlas it works very well

 

[o0norton0o]

The microdigital boyer retards the spark 40 degees from full advance when you kick it over. That's 9 degrees past TDC and yet my bike still occasionally will kick back on me. So, I wonder if any of you who use a tri-spark have ever had the lever kick back at you??? Or does the Tri-spark completely eliminate that???

 

[baz]

Are you saying you start kicking and then turn on the ignition mid stroke

No
I'm saying get the engine in the position it needs to be and then switch the ignition on just before you kick
IE if you've kicked it over and it didn't start turn the ignition off and back on again when you are ready to kick

 

[cash]

The microdigital boyer retards the spark 40 degees from full advance when you kick it over. That's 9 degrees past TDC and yet my bike still occasionally will kick back on me. So, I wonder if any of you who use a tri-spark have ever had the lever kick back at you??? Or does the Tri-spark completely eliminate that???

My tri-spark has just about resolved kick back. On the odd occasion the motor has kicked back it has fired once followed by a kick back?

 

[baz]

I have an antique power hungry Lucas Rita it's never kicked back in decades
I now have an Alton starter running happily with it