Hi All

Bought a new replacement DIGIPLEX 2S as a future spare, but is marked as MED 441A, on my bike unit is marked MED 442A, is there any difference? also where can I get a replacement cable boot, is it a Fiat part?

thanks Pete

I too have bought some as spares with both codes on them. I haven't tried them yet. I believe Guzzi also used them. Some fine day, I plan to swap out each one on my shelf and see if there is any power difference, or if it even runs. I know the one on my bike does not respond to vacuum changes any more, so I have blocked that off. So I am guessing I am missing out on a few degrees of advance at higher RPM.

Some day I will spring for a replacement box, but my Digiplex hasn't died yet.

Cheers,

Got this reply from the dealer....interesting re mention of Guzzi engine?


Hi Peter, same unit different labeling, 442 was labeled for the Ducati and the 441 the Moto Guzzi at the same period
Regards Jim

probably the difference relates to the mapping

inside there is an Eprom with the mapping records, but to swap the chips it will be difficult beacuse i recall them being soldered and covered in black resin.

how about an med 439m digiplex 2 , there is one for sale here and if it fits .....

A friend of mine showed me differrent mapping for this unit (Fiat, Alfa Romeo, Ferrari, Guzzi, Ducati) and told me that it's easy to remap a new eprom, but it's hard to know wich one you need (8bit or 16 bit)

One more question about the Digiplex 2S box.
Does the vacuum tube actually do anything? I would suspect that it advances the timing as it would on other vehicles. But, when I hook up a vacuum pump to it, nothing happens. I started the bike, and tried the vacuum at idle, no response. I tried it again at 2k and 3k. No change.
Could be my box is no longer functioning correctly, or the vacuum line to the intakes is just a ruse by Italian engineers.

Anybody confirm or deny that the vacuum line does anything?

Cheers,

Actually I don't know how the vacuum works on 441a any differend model has spec mapping

The large black unit with 3 screws and the number 2 stamped on it is the vacuum
control unit for the spark advance. You can verify its function with a pump and timing light and 3 hands

I guess I'll open up my box and see what's inside. I assume that there is some form of diaphragm. I can't imagine a 20 year old diaphragm working so well anymore. May need to be upgraded.

Cheers,