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Nr.  198



Complaints in the Zündapp factory





© 2020
h-p hommes 
überarbeitet 2023



Complaints in the Zündapp factory

There are complaint reports from "travelling fitters" at the Zündapp works.
Also correspondence between the Zündapp design office (KB) and the testing department.
The question is, how good were the original made parts?
There are many question marks about the quality and quality control at that time.

For example, today Zündapp KS 750 drivers still consider the original spare part to be the one with the highest value.

For me this has not been the case for a long time.

During my reproduction of spare parts, I checked many original spare parts, of which I also had the original drawings.
The result was often totally confusing,

Of eight original new gear shift dogs only two were really the same.
Often the hardness was unacceptable.
From overhardened to buttery soft.

These errors were often generated during production in the factory.

Gear breakage (complaint report from 08/15/1942)
It says ........................ With the 4,000 Zündapp KS 750 delivered, 3,000 gear breakages are to be expected ...........

I chose this example because I had to make my negative experiences with the ignorant installation of new "top original parts".

My experience here in brief.

-KS 750 gearbox rebuilt only with new parts from me, which have fully proven themselves for 10 years.
-Installed a new original gearshift.
-After only 30 kilometers of driving there was a crashing damage.
-Two gears (2 + 3) engaged together, teeth sheared and V-shaft bent.
-Assembly error? I couldn't imagine.
-Gearbox rebuilt again.
-Again after 80 kilometers the same.
-That made me speculate a lot.
-It couldn't be an assembly error, as I had already assembled several dozen gearboxes without any complaints.
-The only thing that is original was the automatic gearshift.
-Automatic switch examined, but nothing really found that deviated from other automatic switches.
-Automatic switch recognized as a logical source of error and put aside.
-Automatic gearshift replaced by another and the transmission has now been running perfectly for thousands of kilometers.

Only now, by reading the letter of complaint from the Zündapp works, I realized that I had installed one of the 4000 faulty automatic switchgears mentioned in the report,
which caused great concern as early as 1942 and was then changed.

The automatic switch up to 604 ??? was faulty and often caused the transmission to lock.


or me it was always amazing that you could buy a lot of automatic switchgears.
They weren't a rarity.

Today I see it differently.
The automatic switchgears were replaced, but not thrown away.
You could always use something of them again.

The unrecognized defective original parts migrate like a virus from gearbox to gearbox, destroying and causing despair for many.

If you then dismantle them again, they still look great and unused and migrate to the next one, or into the same gearbox to destroy everything again.

What happened to my new, original gearshift?

I have no idea where it is lurking for its next chance.

Maybe it's in your garage?



What is the fault with first 4.000 automatic switchgear?

1. The material of the shift forks was too soft and bent.

2. The safety cam was not high enough.

Then the factory Zündapp also worked sloppily.
The design office had the safety cam heightened in production.
Still it had no effect.
Two gears were still engaged, which theoretically could no longer be possible.

Investigations in the production showed:
That the master mechanic for gear boxes filed the cams all down again, because he believed that this was an error in production.

3. Faulty compensation plate for gear guidance.

None of us throws an original part in the scrap.
So these parts migrate from one to the other and give a lot of joy when buying and even more trouble when using.

I've only described one problem here.
There were a number of problems, mostly due to the use of poor material.

So when I hear "This is still new and original" I always get very thoughtful today.






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