You will most likely never have any trouble in installing or operating your AMM-IMMOGNITION system. On this page, however, we will provide some tips and tricks to get the best performance from your motorcycle.

In case you think, that something may be wrong with your AMM-IMMOGNITION system, we strongly recommend to consult this page, as the information given here may solve 99% of your problems. If you still have a question, please contact me directly via email:

Keep on riding, Charles Altmann.


If you have lost your installation and operation instructions or your dealer did not give you the paperworks that came with your AMM-IMMOGNITION system, you can download it here:

AMM - IMMOGNITION I (dual-fire) manual
AMM - IMMOGNITION II (single-fire) manual

These downloads do not contain the guarantee certificate, since this is an original document, that MUST be handed over to you by your dealer.

The downloadable manuals contain ALL information for a successful installation. If you do not succeed, please read again carefully, and do it exactly as explained there.


Now we enter esoteric terrain. There has been a lively debate over years on what ignition system is better: single-fire or dual-fire.

For the newbie: a dual fire system was Harley's choice for about 100 years. Both plugs give a spark simultaneously, but only one spark occurs in the compression stroke of the appropriate cylinder. The other spark is "wasted" in the intake or exhaust stroke of the other cylinder.

A single-fire ignition system (as included with the newer Twin-Cam models) "knows" which cylinder is in the compression stroke and fires only the active cylinder. No wasted spark in the other cylinder, as with a dual fire system, that actually does not "know" which cylinder is in the compressison stroke. For a single-fire system, two seperate ignition coils or one 2-in-1 single-fire ignition coil is needed (which is sometimes misleadingly called "dual-spark-coil").

Since the "wasted" spark of a dual-fire system can occur in the intake-stroke of the "passive"cylinder it sounds as if such a system is unable to work, since inflammation of the intake gases seems to be unavoidable.

Those who are interested in the geometry of a 45° V-twin engine may take a look at this drawing.

There is actually only one reason why a dual-fire system is able to work. This is because the spark in the cylinder under compression will be much more powerful than the simultaneous spark in the "passive" cylinder. The high-compression leads to an increase in spark voltage, this means that a spark can only occur at a higher voltage. The "passive" spark occurs in the other cylinder that can be in the intake stroke (no compression) or in the exhaust stroke (no compression either). This mandates that the passive spark occurs at a low voltage. The current through both sparks is the same, since they are connected in series in a dual-fire coil (this is also the reason, that if one plug fouls, the other will also not be able to give full spark energy). So there is a high-energy (current x voltage) spark in the compression-cylinder and a low energy spark (unable to inflame something) in the passive cylinder. If you would build a dual-fire system with two independent single-fire coild, giving a spark to both cylinders at the same time, it would work very badly, because there would be too much energy in the passive spark.

I wonder if the designers of the first Harley ignition did know about it, or was it just a lucky coincidence .... ?

However, the advantage of the dual-fire system is: lower cost, since fewer parts and less cables.

The subjective advantage of the single-fire system is, or should I say "can be": better engine response, rock-steady idle, less engine vibration.

If there actually is an advantage in a single-fire system, depends to a large degree on the quality of the ignition coils used. A good dual-fire system with high-quality ignition coils can easily outperform a single-fire system with poor ignition coils.

There was a time, when dual-plug cyclinder heads were en vogue. The theory behind it was, that two sparks give more energy than 1 spark, that there is a double chance that a spark occurs where the fuel mixture is, and that it is a redundant system, since there is an extra spark-plug, that will work if the other fouls.

Unfortunately in real world such a system is not as favourable as one would like to think. Since two dual-fire coils were used, with one dual-fire coil feeding the two plugs of one cylinder, there will not be a significant amount of "more" spark-energy. It is more the way, that the spark energy of the coil is divided between the two plugs. Also, if one plug fouls, the other will also not work properly as both plugs are connected in series through the dual-fire coil leaving only one valid argument: double chance for doing a spark where there's something to burn. But this last argument is more related to idle and starting.

On the other hand, a dual-plug configuration in conjunction with a high-performance ignition system can give you problems where you don't expect them. The right plugs are between the push-rod covers. Some customers complained about idle-problems. What turned out was that the isolation of the plug-boots (between the push-rods) was too bad to hold back the high-voltage resulting in spurious mal-ignitions, since if one plug don't work, the other won't do it either, as they are connected in series in the dual-fire coil. You need high-quality high-voltage-proof spark plugs on the right side of the engine. But there's no room... shit ;)

Today, with high-quality ignition components available, there's no need to go dual-plug. If you already have it on your bike, use it with a single-fire ignition and two high-quality dual-fire ignition coils as showed in this drawing.

Do not use a dual-plug configuration with a dual-fire ignition system, since you would have to connect the ignition coils in parallel or series. Connecting multiple ignition coils together, is always a bad idea.

One very popular question: Does one ignition system give substantially more max. horsepower than another?

I presume that we talk about two ignition systems that are of acceptable quality and that both systems are correctly adjusted.

The answer is: No. The maximum horsepower will be quite the same whether you use dual-fire, single-fire or dual-plug. It can however be that one system gives a smoother power curve with more torque and much more fun to ride. This is your AMM-IMMOGNITION in conjunction with a good ignition coil.


The most important value of an ignition coil in conjunction with a specific ignition system is the primary resistance. The primary resistance of the coil must match the required value of the ignition. The AMM-IMMOGNITION works best with coils that have a primary resitance between 2 and 3 Ohms. Coils with higher primary resistance are only suited for ignition systems that use mechanical advance.

Ignition coils with a lower primary resistance than 2 Ohms can be used with the AMM-IMMOGNITION only if a coil-pre-resistor is used with a value that the series resistance of the coil and the resistor is between 2 and 3 Ohms. I'll give you an example of it later.

The primary resistance determines the amount of current that will flow through the ignition coil. Ignitions using mechanical advance are not able to control the dwell time of the coil. Therefore the primary resistance must be high (4..6 Ohm) in order to prevent overheating of coil and maybe output-transistor. Mechanical advance ignition systems supply high-spark energy during low rpm and low spark-energy during high rpm.

Computerized ignition systems (as the AMM - IMMOGNITION) calculate the dwell time of the coil in order to allow for a constant spark energy over the entire rpm-band. They must be used with lower-resistance ignition coils. The dwell-time of the AMM - IMMOGNITION is internally set to 8 milli-seconds, thus giving high spark energy with 2..3 Ohm ignition coils. If you use higher resistance coils with a computerized ignition, the spark energy will be poor, resulting in bad starting and bad engine performance. If you use a coil with a lower resistance than specified there will not be more spark energy but more heat dissipated in the coil and in the output transistors, and components may be destroyed. So keep with the specs, please.

There is another important value with ignition coils, that is: inductivity. The inductivity determines the energy and the speed of the coil. A high inductivity gives high energy but low speed. A low inductivity gives lower spark-energy but higher speed.

The actual spark energy is calculated by the formula: E = 1/2 x L x I ^2 (with L= inductivity and I = coil current).

As you see the coil current I is squared. That means if you double the inductivity L, the energy will also be doubled, but if you double the coil current I, the energy will be increased times 4 !!! (4 x I -> 16 x E, 8 x I -> 64 x E, e tc.)

This is important to understand: we can have a high energy coil with a small current, but it will be slow.

But we can have a much higher energy coil which is also fast, if we use a low inductivity and a higher current. That's the trick. With such a coil we need a fixed dwell time that matches the coil, else it will get hot and break down.

Therefore it is essential to be within the specified values for the primary resistance of 2..3 Ohms.

We have tested a number of ignition coils from different manufacturers with our Nitrogen pressure-chamber. We would like to recommend the following brands: Accel, Andrews (orange for single-fire), Dynatek (green for single-fire), Harley (of the Evo-models), RevTech.

If a manufacturer is not listed above, we may had not the opportunity to test their coils, or they were too bad to be mentioned here.

If you need to use the small Nology coils: These are made in Germany by PVL and were designed for the newer Triumph bikes. The problem with Nology is that they sell them with a wrong spec. (3 Ohm). In fact these coils have only 1.4 Ohm and must be used with a coil-resistor in order to reduce coil current. These coils are okay.

The Nology guys have another product called power-core. This comprises a coil that is connected in parallel to your ignition coil, raising inductivity and thus spark-energy. The problem with that product is that it doubles the current that is drawn from the ignition (the extra energy must come from somewhere). Therefore the application will be out of spec, unless you add a coil resistor (1,5 Ohm / 50 Watt). But then the extra energy will be lost. So this is basically a non-sense product.

Now what coils are really best (my personal point of view and related to pressure chamber testing) ?

In conjuction with the AMM - IMMOGNITION I (dual-fire) use a standard Harley dual-fire coil as mounted on any '90 Evo-model. No joke. This coil really provides lots of energy while maintaining immaculate high-voltage isolation. This dual-fire coil is unrivalled.

In conjuction with the AMM - IMMOGNITION II (single-fire) the easiest and high performance way is using the 2-in-1 Screaming Eagle coil #31746-98A. Here's the 2-in-1 installation drawing.


A very common question. How to use a standard tachometer with a single-fire ignition. We have developed a very simple adapter that you can do yourself with parts that cost a few cents. Here's the plan: single-fire rev-adapter.

It looks like this: picture of rev-adapter

Pay attention to the polarity of the two diodes. Twist and solder the ends together. Isolate the whole part with shrinking tube.


Something that is not really a good combination is: a high-compression engine plus a small weak battery. The starter motor causes the battery voltage to drop during starting. If the battery voltage drops below 4V (sounds incredibly low, but it can happen) the internal computer of the AMM-IMMOGNITION will reset and shut coil current down, resulting in a spark during the compression stroke (causing a backfire). This is not an acceptable situation. A larger or more powerful battery should be used. As this is not always desirable on custom bikes (no, we don't want a big battery), we need another solution.

If we could buffer the supply voltage of the ignition system during the starter-motor's high-load compression turn, the system would remain operational ensuring very good starting behaviour. Back-fires will also not occur. It is done with this high-compression starter circuit.


I love kick-starting. I have a kick-starter on my Electra-Glide (with the E-starter disabled) and I would also love to install a kick-starter on our TwinCam Dyna Sport test bike. Unfortunately kick-starting is not possible with the new TwinCam engines because the engineers avoided kick-starting by incorporating a very stupid sensor-system that gives no instant engine-phase information. The sensor system of the late Shovels and the Evos (cam driven trigger rotor) was simpler and better, as it gave real-time information and was manually adjustable.

However, if you use a kickstarter on your Pan or Shovel or Evo together with the AMM - IMMOGNITION you should know the following facts:

An electronic ignition system generates a different spark than a mechanical points system. A point system generates a kind of a high-speed multi spark, since an oscillation occurs when the contact is lifted.

An electronic system generates only one single big spark when the transistor is switched off. The effect of this is that the electronic system works better with a leaner mixture or in other words, it is more sensitive to fouled plugs. That means if you come from a points system and your kick-strategy was - 3 pumps and lets go - you may have to elaborate a new strategy.

You should adjust the acceleration pump of your carb to a minimum value. If the engine does not start after 5 kicks, you should have a look at the spark plugs. These will be either dripping wet or totally dry. If they are wet, screw down the accelerator pump. Mikuni and S&S carbs often come with a bad pump setting (too much fuel).

Remember, the acceleration pump is not needed for accelerating the bike during riding, its only purpose is to smoothly rev up the engine from idle speed (400..800 rpm) to clutch-release speed (1500..3000 rpm).

If you still have wet plugs after turning the acceleration pump down, you kicked too much with pulled choke. As a rule of thumb, do not do more than 3 kicks with pulled chocke. Then continue with decactivated choke.

Once you have found the right fuel mixture, kick-starting will be very easy, also with larger displacement engines.

Some more facts:

On late 1340 Shovels it is advisable to use spark-plugs with long electrodes (as OEM).

Check that the ignition coil(s) are within the specified primary resistance (between 2,0 and 3 Ohm). If you use coils with larger primary resistance (4..6 Ohm) the engine will have poor starting behaviour, because only a weak spark will be generated.

The AMM - IMMOGNITION receives engine phase information from the OEM trigger rotor. A signal will be generated at 50 deg. BTDC and on TDC of each cylinder. On 50 deg. BTDC the coil will be loaded, and on TDC a spark is generated. However the system cannot recognize if the engine rotation is forward or backward. What I want to say is, that when you kick down the starter pedal, searching compression, you should not move the engine way up into the compression stroke but only to the point, that you feel the compression to begin. Then raise your foot (and pedal) and slowly kick the pedal down, doing a complete engine stroke.

If you do it wrong: move hard into the compression (less than 50 deg. BTDC), and then raising your foot for kicking the stroke, the engine will rotate backwards while you raise your foot, and a backfire will happen at 50 deg. BTDC - puff -. This way you will not be able to start the engine.


The following hints refer to all-day riding requirements, not racing and not show:

As for the spark plugs there's not much to say, except that you should always use suppressed (with internal resistance) spark-plugs. The other part is the electrode position in the combustion chamber. This refers mostly to starting and of course kick-starting. For some engines, i.e. the late 1340 Shovels it is essential to use a spark-plug with a loooong electrode. This japan-made Accel plug worked in my Electra-Glide for almost 10 years. As you see, it can tell a story.

old used accel plug

The electrode gap should always be set to 1 mm. High-quality spark-plugs are made by Accel, Beru, Champion, and ... many other brands. You should however not use non-suppressed (zero-resistance) spark-plugs (like the Beru Silverstone). I will explain later.

As for the ignition wires they differ in core and isolation. Core materials are carbon fiber (suppressed), copper (not suppressed) and stainless steel (not suppressed). Isolation of the cable and the boots is made either of silicone or hypalon. The silicone has better isolation properties whereas the hypalon is mechanically more robust and easier to crimp.

You can operate your AMM-IMMOGNITION with non-suppressed cables (copper or stainless core) but you must use a suppressed spark-plug.

As I enjoy to make ignition wires myself, I personally prefer cables with a copper core and hypalon isolation. They transmit high-energy impulses, are robust and easy to crimp. Please, do not make your own ignition wires, unless you have the proper tools (crimping pliers especially for ignition connectors) and know what you are doing.

Braided steel spark plug wires are still en vogue. From the standpoint of a ignition-systems manufacturer I have to tell you that braided steel ignition wires are severe bullshit. Every manufacturer of ignition wires will advise you to route your ignition cables as far as possible from any metal part. Do you remember the neat metal clip that clamps the front cylinder ignition wire to the top-engine-mount ??? That part was later changed to plastic. Guess why. When the cable broke down, it was at that point.

The spark will always go the shortest way. If theres a shorter (less HV required) way than the electrode inside the combustion chamber, the spark will follow it. The job of the ignition cable's isolation and boots is to prevent that there is any shorter way. To cover the entire ignition cable with a metal mesh and then ground the whole assembly, is from a technical standpoint a really stupid idea. The life expectancy of the cable will be greatly reduced. Such a cable will fail sooner or later. If you drive through misty weather and get misfires you know that the time has come to throw that garbage away.

Anyway, if you're addicted to the looks of braided steel cables, I can understand that you have to use them on your bike. Then just take a spare of real-ignition cables with you, if you go for a longer ride.

What about nology hot-wires?

As long as you do not need them for top-fuel drag-racing, you don't need them at all.

These cables also have a reduced life expectancy (at least in rainy weather). They are specified to be used with a non-suppressed spark-plug like the beru silverstone. Just don't do it. These cables emit a high-frequency high-energy radiation that interferes with a) electronic equipment and... b) your bio-system, since they can burn your skin through the trousers. If you are concerned about continuously using a cell-phone, and if you still plan to have a family, you should not go for a longer ride with hot-wires near your balls.

Anyway, if you can't let it, the AMM-IMMOGNITION will work together with nology hot-wires.


If you experience an engine stall during riding (or during switching lights), it is most likely that the supply current of the AMM - IMMOGNITION has been interrupted and the system has activated the immobilizer. If this happens you should check your motorcycles electric system. A current interruption can be caused by faulty ignition-swich, kill-switch, circuit breaker, connection cable, battery terminal. If you don't believe that your motorcycles electric system is the cause, you can do a simple pepsi-test: Route a cable from the coil-plus terminal (NOT COIL MINUS) directly to the battery-plus terminal. If the problem does not appear anymore, it is proved that somewhere in between there's a bad contact.

Another 'solution' to this problem is to deactivate the complete immobilizer function of your AMM-IMMOGNITION with the AMM-IMMOLATOR-KEY. Its just a one-touch procedure and it is reversable. It is not really a solution, because your faulty electrics are not corrected, but the engine-stall symptom will disappear. Check out your local dealer.


It is extremely unlikely that you run into a problem that cannot be solved using the information given in the instructions and on this page, but it is of course not impossible.

If you think that there is really something wrong with your AMM-IMMOGNITION you can of course return it to our factory for a thorough check. You should however request your return by email with a full error description, because we may help you finding out where the real cause of the trouble hides.

Checking and repairing your AMM-IMMOGNITION system is free within the 5 years warranty period as indicated on your guarantee certificate. You have however to pay the shipping costs both ways. Use this return form for sending us your AMM-IMMOGNITION system. You have to declare the customs value to US$ 0,00 (notify: motorcycle ignition, return for repair) else we cannot get it out of the customs and the package will bounce back to you or... who knows.

We will check and repair immediately after reception and send back via FedEx (US$ 50,- your cost) to you with a full investigation report. Please include your guarantee certificate and one of your activation keys.


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