Weak ignition, the engine no longer restarts when hot, it stalls, sputters... you've checked everything 12 times, replaced everything, and yet... you still end up pedalling or pushing?
Are you sure about the quality of your capacitor?
What is a capacitor?
When you use an electrical appliance or even flip a switch, a small electrical arc is created every time.
This is called the “self-induction effect”, i.e., the production of an instantaneous, autonomous voltage caused by a change in the contact's state.
In an engine ignition, this effect is used: the opening of the igniter contact creates a self-induction effect on the primary circuit of the ignition coil, and this effect is amplified by the secondary circuit, causing the spark plug to spark.
So you'll tell me if everything works like that, why a capacitor?
Because the capacitor plays a somewhat "organizing" role in the self-induction effect.
Thus, the capacitor will be able to rapidly release all the stored energy, optimizing the self-induction effect and therefore allowing a "snappy" spark plug spark.
It protects the breaker points from voltage surges and prevents them from wearing out too quickly.
Finally, and more "technically", when the spark occurs at the spark plug, there is a "resilience effect" caused by the high voltage of the ignition coil's secondary circuit. This "overvoltage" is thus "stored" by the capacitor, which will return it to the next ignition cycle, and we start again at point 1!
So the capacitor is an essential element in the ignition circuit, but it is not the cause of ALL so-called ignition failures!!!
If your coil is no longer within resistance standards cold or hot, if your breaker points are oxidized, worn, or dirty, if an element of your ignition is cut, melted, or grounded, if your spark plug or spark plug wire is cut or dead, a capacitor, whether electronic or otherwise, will not solve your problem!
However, as we have just seen, a capacitor "takes a lot" during its life and is considered a "wear part", just like a spark plug, a tire, or a pair of brake pads.
So, it's always in your best interest to start with new parts when completely overhauling your ignition.
"Old" capacitors worked better
And that's true because their design was rigorous and used specific products.
Indeed, most old capacitors were "oil-filled." Let's say rather that it was a winding of paper and metal impregnated with an "oily" product.
Unfortunately, this effective and inexpensive product was polychlorinated biphenyls (PCBs), also known as "pyralene" (although this name is actually a brand name of... Monsanto... him again 🙂 ).
PCBs have formidable dielectric qualities, decompose at 1000 degrees, are chemically inert, etc., etc.... so it was the ideal tool for manufacturing capacitors and other transformers.
Unfortunately, every miracle product has its downside, and PCBs are highly toxic to humans and nature alike, so their use has been banned (since 1987 in France).
Since that date, remanufactured products no longer contain this substance, which is one of the main reasons for their "fragility" or even "uselessness."
To replace PCBs, the industry has turned to substitutes: silicone oils, synthetic oils, or even vegetable oils like castor oil. This is what you find today in some so-called "oil-filled" remanufactured parts.
However, if a quality substitute is not used, you end up with the same problems of capacitors failing quickly...
Moreover, all these capacitors age badly because they end up "leaking" or "drying out" and therefore... burning out.
And what about the electronic capacitor in all this?
Well, it's a simple, and above all, easy and quick solution to implement.
For "electronics", technically they are known to be reliable and small.
This small size allows them to be installed in place of the original capacitor without the hassle of installing an "external" capacitor. This greatly facilitates both restorations and the look, which remains original.
On the other hand, this small size allows, when absolutely necessary, to integrate the electronics within the metal body of the old capacitor itself. A small note on this point: take all precautions when doing this kind of manipulation! You will be cutting and tinkering with a capacitor that very often uses PCBs! Let the Workshop that offers this kind of integration do it.
Another advantage of electronics is their thin metallization, which allows for what is called "self-healing," meaning (very schematically, apologies to purists!) the ability to regenerate in case of an excessive "voltage spike."
Finally, the last advantage is that they are made of polyester or polycarbonate and therefore age very well.
But does an "electronic" one really work?
L'Atelier de la Vigne has "freed itself" from the inherent problems of old capacitors by focusing on the assembly or adaptation of electronic capacitors, reliable and practical elements that can replace almost all existing old capacitors.
Personally, I've been using this part on all my collection for years without any problems.
However, self-satisfaction has its limits 🙂 and, moreover, I use my vintage machines occasionally, on "quiet" rides, and apart from 3 or 4 "special" machines, I rarely do "road trips" or "raids."
So, when Sébastien, President of a Solex fan club "Solex Aventure 17", contacted me to finalize the ignition of a group of Solexes leaving to tour Corsica this summer, I saw a good opportunity to put the "electronics" to the test.
To discover this "road trip," I can only direct you to the Facebook page of this dynamic Club!
A trip undertaken this summer in... Saharan temperatures 🙂 and in mountainous terrain conditions... for those who know Corsica!
The "electronics" held up well and therefore remain a simple and effective alternative to replace all our old capacitors (mopeds, motorcycles, cars).
So don't hesitate, go electronic 🙂
As for the final word, I'll leave it to President Seb, I quote:
"Very clearly, we are very satisfied with your capacitors. I've driven more than 3000km with them, no problems. All the friends in the association have electronic ones now. No more long-term worries. Thanks to Atelier de la Vigne 38."
Thank you very much, and congratulations on this raid!
Note: the author of this article is neither a physicist, nor a chemist, nor an electrical or electronics engineer. He apologizes in advance for the way certain things have been written to popularize and simplify as much as possible for the understanding of the greatest number. More knowledgeable comments are welcome. Thank you.
More news from Atelier de la Vigne?
click here!