Tachometer intermediate unit

[jdj123]

Hi to all electrical experts.

My tachometer is not working at all when connected with the twin plug dizzy , the 2 BHKZ CDI and the 2 coils.
It's a green gauge tacho (8/65) that I've sent to Switzerland to be modified ( 10000rpm screen + BHKZ compatibility)

I read on the forum, that in 69/70 the BHKZ were completed by an intermediate unit in order to have the tachometer working properly.

I would like to find a solution as replacement of the large, tall, round aluminum can on the electrical panel that is missing on the electrical panel
The Bosch number on this item is 0227 990 001.

It is a TACHOMETER INTERMEDIATE UNIT which seems to be impossible to find( NLA)

Basically the "intermediate unit" is a coil running in parallel with the points, when the points are closed, the coil charges up, and when the points open, it discharges into the tacho input lead.

could you please suggest what would be the correct wiring possibility to have this tacho

Thanks to all in adavnce.

regards
JD

[304065]

Jd,

Who modified the tachometer and what did they do to it?

[66S]

You could use a Tach-Adapt if appearance is not a problem, it is a pretty versatile device. i have quite a few of the Bosch int. units but they will not be accessible until the snow is gone, lots of snow.....

[jdj123]

Hi 304065,

the tachometer was rebuilt in Switzerland, by Anthony WEST in 2009 and I never tried it before 2014.


Anthony West
c/o Christel Radau
Im Silberbott 16
79599 Wittlingen
Germany

anthony@anthonypwest.com

phone: +41 79 601 34 25

I don't know in details what was really technically done except the fact that the tacho was adapted to BHKZ.

[Richardnew]

One of my recent Vintage Motorsport columns deals with gauges and gauge repair.

Richard Newton

[sithot]

A little late but here are the instructions for the Bosch Part # 0229-990-001. FWIW.