ignition for Zündapp KS 750 and BMW R 75
Out of the book: Zündapp
KS750 und BMW R 75 Wehrmachtsgespanne
gestern und heute page 36/37
The Wehrmachtsgespanne were built with a magnet
ignition again although former models Ks 600 and BMW R 71 were built with a
battery and coil ignition. The magnet ignition gave a better reliability,
because it was independent of the generator and the battery.
There were two different products:
ZGA2 and the Bosch FJ2 R134.
with Noris and Bosch magnetos
When the bike starts well with a cold but does
not start with a warm engine because the spark is not strong enough,
then this is a sign that the coil is damaged and
has to be replaced.
Turn the engine on TDC, so that the arrow -B-
shows to the left side on the advance ignition. This shows that the left
cylinder is in the expansion stroke. Now the contact
breaker should start to open. Then the ignition is adjusted correctly.
verification turn the engine half a turn further so that the contact is closed
and then put a piece of cigarette paper between the contacts. Now you
turn the engine slowly to TDC. When you can take the paper off the TDC sign
should be in the middle of inspection hole.
If not, you have to regulate the ignition timing
by changing the ignition gap accordingly. The ignition gap could be between 0,2
and 0,5 mm.
The ground plate -A- may not be
turned at any point.
The ground plate -A- was adjusted by the factory. With this ground plate the highest firing voltage is adjusted (position between armature and magnet).
If you need spare for the Noris you can order it by this spare part No.