Occasional kickstart hiccup

I have a boyer microdigital (red box) ignition on my 70 commando. Sometimes, this scenario happens:

1) I drive the kickstart around to get it into position where I feel the resistance from a piston starting it's compression stroke.

2) I'll start to set myself to launch upward so I can drive the kickstart down powerfully, so I will be able to give it a good strong kick.

3) As I leap upward, the tinyest motion of my foot on the kick lever causes a spark before I can even begin to drive my weight down on the kickstart and I get a weak hiccup back through the carbs.

Anyone have this happen occasionally?

I have my bike timed at 31 degrees @ 5000 rpms, so I'm thinking maybe my timing mark is off by a few degrees and this is causing the occasional premature triggering of a spark when I set myself up to kick start the bike. It doesn't happen all the time, probably because I'm not all that religious about rotating the engine to the same spot to kick from every time I start it.

This sound familiar to anyone? opinions please.

I have a red box Boyer on my 441 Victor that randomly pops back through the carb. I always figured that there must be an itchy capacitor in the red box that doesn't need much provocation to discharge...

Once in about 10,000 (more or less) starts, cars or motorcycles with points ignition when fully or near fully warmed up, I'll turn the key and the engine fires off and settles into an idle without using the starter/kicker. I think the Boyer MicroDigital's propensity to tolerate reduced system voltage is due, in large part, to a capacitor that charges quickly and is meta-stable.

There are a few members that can give you the deep-down' I believe that DynoDave wrote a treatise on the subject.

I interpret the anomaly as my ignition is anxious to join the rest of the mechanical/electrical team and take me for a ride...

o0norton0o said:

It doesn't happen all the time, probably because I'm not all that religious about rotating the engine to the same spot to kick from every time I start it.

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Therefore no real reason to think the spark is premature or any cause for concern unless you are also experiencing kickbacks?

As it's a wasted spark system, both plugs fire spark simultaneously and the Micro-Digital red box units produce a strong spark at low speed, so I would guess the occasional 'phut' or 'pop' you hear is probably the mixture igniting in the 'open' cylinder from the wasted spark and blowing back through the carb. If it was the mixture igniting in the cylinder under compression you'd get a kickback.

RoadScholar said:

I always figured that there must be an itchy capacitor in the red box that doesn't need much provocation to discharge...

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awesome, itchy circuitry! It's good for me to hear other people observe this kind of thing and wonder, "WTF causes that?"

L.A.B. said:

I would guess the occasional 'phut' or 'pop' you hear is probably the mixture igniting in the 'open' cylinder from the wasted spark and blowing back through the carb. If it was the mixture igniting in the cylinder under compression you'd get a kickback.

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I would say, "phut" is pretty close to the noise it makes, and it's very weak. I'm certain that I cause it with the weight of my foot on the kickstart causing a tiny amount of motion of my ignition magnets which the "itchy" boyer 8) capacitor attempts to scratch prematurely....

Thank you both for your comments. My OCD has been abated (for now...) My bike really runs very well. I was just curious WTH that weird occasional "phut" was, and of course, more importantly WHY?.

I had a strange one with my Red Micro digital -Power ignition. Occasionally the motor would kick back and as my foot dropped back down onto the kick start it would just fire up and run ??

Boyer checked it out a couple of times to no avail, and there was always something lacking in the bikes performance. I've still have it, stored away in it's cardboard box, a TriSpark replaced it and what a difference.