Powerdynamo brings new ignition & light 
to your classic bike



electronic revolution counter (Tachometer)

Note The issue of electronic tachometers (revolution counters) is unfortunately much more complicated than you might think. There are countless versions and plenty of differing technical situations the unit might work in. Many customers think they just need to know where to connect the tachometer and all is settled - well it definitely is not.
Under no circumstgances connect your tacho to a wire of our ignition system. You not only risk ignition failures, but also destruction of your tacho.
  In most cases your stock tacho will not work with our material.  Definitely not in cases where it had been connected to the points (contact breaker) as it than expects negative impulse, whereas electronic ignition deliver positive.
  It does not make any sense to ask us whether your electronic tacho XYZ will work with our material as we will most likely not know this material. 
What will always work  are tachos which take the pulse inductively (by a few windings of wire around high tension cable) from wire that runs to the spark plug. Here the only matter to consider would be how many sparks you get per revolution (some of our systems give 2 or even 3 per revolution). As far as we know Kovo offer such instruments.


our solution

is based on  Instruments of type EEDM made by MMBThis solution  consists of a small module housed in a relay box which brings the frequency signal from our alternators to a signal the MMB Tacho can correctly reed. The module gets connected via some distributer cable (arriving with the module) between alternator and ignition coil (or advance unit, depending on model). 

We have seen that MMB now offer a new generation of tachs which we have not tested with our solution. Also they do not mention any more whether the instruments are oif the known EEDM type. Our solution refers to MMB  instruments of type EEDM and had access to them for testing. It might well be that other makes also work, but we did not test and we will not test. This testing is a time consuming process, would possible involve changes on our modules and it carries the risk that we destroy the instrument during tests. So we do not do so.
Note MMB is now offering a new generation of instruments based on step motors. We have not tested those and, when we look at the information available, we do not think that they will work with our material and solution.

You need 

  • an MMB instrument of type EEDM which can read a positive pulse in a ratio 1:1. This is true for the presently offered EEDM instruments from MMB. This ratio is independent of how many sparks your Powerdynamo system delivers per revolution as it does not take the pulse from ignition, but from the alternator  
    You may choose housing, dial and illumination when buying online with MMB

  • our tacho module (adapter)

  • battery 12V in the system to drive the tacho needle. We no longer permit use without battery to prevent possible negative effects on the instrument. Under no circumstandes input any voltage from the ignition pole of the Powerdynamo stator (red wire from stator) directly into the tachometer. This would destroy the instrument. Always use the wiring adapter we deliver with the module to prevent wrong wiring.

  • If the battery in the bike is only there to drive the tacho, imperatively connect its negative pole to motorcycle ground. Otherwise the instrument will not work! This missing connection is the most frequent reason for failure.

    MMB offer a 6 to 12 converter  for instruments running in 6V environments

Stock revolution counters possibly existing on various motorcycles can normally NOT be driven with signals from our systems. It may be that they function, it may be that they do not or wrongly so. We can not tell and we do not know and therefore we can not offer any support on those materials.

Same is true for aftermarket Tachometers other than MMB. As there are so many makes and versions, we have not tested the solution in combination with instruments of other makes.

We know however for sure that - very unfortunately -  it does not work with the Pitsch LZ13. If however your stock points had not been sitting on the (now gone) dynamo/alternator, but the camshaft or as in some cases the other side tof the crank, you may keep them to drive the Krober (see tip below).

If your stock Tachometer has been  driven by points (contact breakers) which will not get eliminated by installing Powerdynamo (as they sit either on the camshaft or the other side of the crank)  you may keep the points to drive your Tacho and all is fine again.