Ducati Sporting Club UK > DesmoDue Race Series > DesmoDue - General Questions and Chat > 620 engines SS/Monster/Multi are they all the same?

[skidlids]

Apart from the amount of gears already mentioned

the Early ones have a standard type clutch and later ones come with the APTC clutch.
Electronics wise the early ones don't have the neutral feeding into the ECU where as the later ones do as part of the start interlock system.

Although your not stuck with Standard ECU as there are Options
Such as
Standard ECU reprogrammed (setup on a Dyno by either CJS or BSD) and the IMMO removed so you don't need coded clocks or a key, if going this route I would change the TPS for a Linear one

1.5M ECU such as Andy Challis uses, limited to about 8500 rpm by the rev-limiter. Although these can also be reflashed (Direct Link software and key) and the rev limiter moved as per the one on Dallas's bike. As the 750SSie uses the same stoke as the 620 your better off using its ECU than the one off the 900SSie

Another option woulld be the good old 1.6M ECU as used on 748/916/ST2
with a EPROM programmed to suit, as the 748 Shares the same stroke as the 620 I'd go with a 748 chip for the ignition curve

Also after market units such as Nemesis and FIM can also be used

On my spare bike I'm currently looking at using a 998 ECU with the 750SSie Injectors as that ECU knows nothing of coded clocks and runs a normal rev counter, I make it about 11% that I would need to reduce the fuel by using a Power commander

[Imola Duke]

Originally Posted by skidlids

Another option woulld be the good old 1.6M ECU as used on 748/916/ST2
with a EPROM programmed to suit, as the 748 Shares the same stroke as the 620 I'd go with a 748 chip for the ignition curve

This maybe a daft question .....
The 1.6m is for a watercooled engine and uses water temp sensors in the loom.
Do you bypass this ?

[skidlids]

No Steve the Oil temp sensor in the front rocker cover of the 620 does the same job.
to go with the 1.6m ECU You would need the 748/916/ST2 harness, MAP Sensor and Air Temp sensor

[Imola Duke]

Originally Posted by skidlids

No Steve the Oil temp sensor in the front rocker cover of the 620 does the same job.
to go with the 1.6m ECU You would need the 748/916/ST2 harness, MAP Sensor and Air Temp sensor

Thats good news then! i have a st4/2 1.6m ecu and harness complete in my shed!
Ecu has a ducati performance ST4 eprom fitted at the moment.

[skidlids]

The 4.5mm longer stroke of the ST4 may cause ignition timing issues, but then again the EPROM may have a advance curve that works, hard to tell until its tried.
As for fueling which injectors did the ST4 use was it the green ones, if so a Powercommander should easily be able to sort out the air/fuel ratio.
Only other concern is the TPS as the connector is different but the signal should be OK as the Mathesis can test both

[Imola Duke]

Originally Posted by skidlids

The 4.5mm longer stroke of the ST4 may cause ignition timing issues, but then again the EPROM may have a advance curve that works, hard to tell until its tried.
As for fueling which injectors did the ST4 use was it the green ones, if so a Powercommander should easily be able to sort out the air/fuel ratio.
Only other concern is the TPS as the connector is different but the signal should be OK as the Mathesis can test both

Thanks Kev
Prob easier to get hold of a st2 harness.
Good thing about 1.6m is you see lots of s/h pc3's up for sale for this type ecu.

[Imola Duke]

After a busy period at work as you know Kev! We will meet so you can collect to forks
Questions!
1.6 ecu fitted with st2 eprom and fit PC3 ?
st4 loom (with green injectors) can be used on the 2v injector bodys/injectors ?
The st4 loom complete with MAP and Air temp sensor will work on a 620 engine ?
Hope this makes sense ? Just finished a nice bottle of red