I don't get very excited when i see electronics anywhere near heat. What it means is that it will fail on you at some point - depending on the robustness of the electronics and the amount of heat exposure/time its given.
We have what's called the 'Arrhenius' equation.
http://en.wikipedia.org/wiki/Arrhenius_equationHere is a quote taken from the following site.
"A historically useful generalization supported by Arrhenius' equation is that, for many common chemical reactions at room temperature, the reaction rate doubles for every 10 degree Celsius increase in temperature."
All this really says is that reactions double for every 10 deg C increase. This is the same reason that dirty clothes/dishes get cleaner much faster in hot water instead of cold.
The same goes for electronics. The more heat you expose them to, the more you are lessening their lifetime. In other words, they 'age' a lot faster under that heat. I am an Engineer, so i tend to look at things like this.
Underneath the points cover of your sohc actaully gets really hot, especially after a hot soak. Go for a good ride, park it & let it sit for a few mins, then try and touch it.
People will say, but electronics are so much better these days. Yes, i would agree, that is a true statement. You have to remember that the Arhenius equation isn't going to go away in the next 1000 yrs or so either. So even though 'modern' components are so much better, they too one day will die.
I'm hoping that you are now starting to see that having electronics under that points cover is not the holy grail of all things. There are a number of ignition systems on the market where this is the case. Whatever your thoughts on ignition points are, whether you love them or hate them, it's true that points are far more robust than any electronic component under the points cover. They are simply immune to heat issues when compared to an electronic component in that environment.
Hondaman has taken an approach that i like with his ignition, which is to keep the transistorised module away from heat, thus only using the points as a triggering mechanism. From a 'Good Engineering Practice' perspective, this is a better way of doing it. The points (triggering mechanism only) can take the heat all year long - year in - year out - and the box just continues to work because it is away from the heat, probably with a near zero failure rate of the box.
The Pamco ignition is also a good ignition system, however all its components are under the points cover. Pamco Pete has made an effort to chose his components wisely with due consideration to heat ratings. The main components he has chosen are not overly affected by heat due to their high heat rating, but they are still exposed to it. Time will tell how long the components will last. My guess is that it will be a very long time and its not something people should be worried about. At least, no more worried about it than if your car's ignition were to suddenly die one day, because both are using similar rated components.
For other system like Dyna, I've heard both good and bad things about them. Some people swear by them and others would never buy one again.
I think when someone talks about dyna, they should distinguish between a plain dyna system and a dyna 2000. The dyna 2000 seems to be an ignition 'done right' to me as it has its ignition module away from the heat, and in doing so, also contains a microcontroller that handles the ignition advance. As long as the triggering mechanism is robust and immune to heat, then this system should last as long as the bike.
Cycle-X ignition is also under the points cover. I actually really like this type of system in that it does away with the advancer as well, but the Engineer in me looks at the electronics that are subject to heat & how long things are going to last. I'm sure its a sturdy unit & that the designers thought about components and heat exposure. I like the idea of a high resolution optical sensor, but you need to ensure the underneath of that points cover stays *clean*.
One thing i look for in an ignition system is if it contains electrolytic capacitors and if the capacitors are subject to heat. Electrolytic Capacitors these days (unless military spec) are plainly crap and you can expect them to fail if you keep it long enough. When electronics parts fail, its generally these caps that are the first to go. Resistors and some IC's are quite robust and can usually go on if the caps are replaced.
I have said the above for a reason regarding caps. I have recently found another sohc ignition system on the market (yet a different one to those mentioned above - i won't mention it). This system contains an electrolytic capacitor under the points cover. Personally, i won't touch it.
As for me, I have a pamco and am quite happy with it. I expect it to last a good while and i'm not at all worried about being stranded anywhere with it. If and when that happens, i'll deal with it then. In general, i'm treating it no different to having something similar fail on my car. The pamco is also a very simple unit and could be serviced at home by someone who is knowledgable in electronics if a component was to ever fail.
Looking at all the pros & cons of each system is interesting & like everything, there is always the value for $$$ that needs to be considered. Hopefully this can give you something to think about when making your selection.
