904 cc Engine history

[rorschach]

So i'm interested in what year the 904cc engine appeared like we know it.
I know only from 1992 when they announced the Monster.



I'm searching the internet but nothing to solve the puzzle
Some bits and parts relating to a SS and a "Paso" ..?

Any imput (links, documentation etc) is of great help.

Thanks

[Speeddog]

The Paso had a similar motor, the 906, it was 904cc but was water-cooled.

AFAIK, the 904 air-cooled motor first appeared in the 1989 900SS.
Unfortunately, it retained the Weber automotive carb. 
The 1990 900SS had the Mikuni carbs like what was fitted to the Monsters.

According to 'The Ducati Story' by Ian Falloon.

[Slide Panda]

Wasn't it used in the Caviga Elefants in 1990+

[ducatiz]

The Paso had a similar motor, the 906, it was 904cc but was water-cooled.

AFAIK, the 904 air-cooled motor first appeared in the 1989 900SS.
Unfortunately, it retained the Weber automotive carb. 
The 1990 900SS had the Mikuni carbs like what was fitted to the Monsters.

According to 'The Ducati Story' by Ian Falloon.

The Paso 906 (called a 906 because it was the first 6 speed 900) was a stroked Pantah case -- including the right-hand side clutch slave.

The water pump and watercooled heads were a kludge, more or less (umm).  The bottom end of that motor was pretty much indistinguishable from a Pantah.

The DCNF carb really wasn't so bad once you restored the European jetting and springs.  It was leaned out like crazy for the US market.

The first year the 904 was used (in the same basic form thru 1998) was the 1989 900 SuperSport.



This bike was never imported to the USA. The first year we saw the new desmodue 900 (904) was 1991 with the white frame 900ss.

The 1989-90 SuperSport was essentially the lineage of the 750Sport, but had 17" wheels, semi-floating rotors.. It retained the conventional RSU forks (M1BB or M1R depending on the model).  Same basic frame as the 750Sport.

[Speeddog]

The Paso 906 (called a 906 because it was the first 6 speed 900) was a stroked Pantah case -- including the right-hand side clutch slave.

~~~SNIP~~~

Falloon says the 906 was based on the 851 cases.

[ducatiz]

Falloon says the 906 was based on the 851 cases.

It was.  Which was a punched out Pantah with water cooled heads..lol

[Speeddog]

It was.  Which was a punched out Pantah with water cooled heads..lol

so a Pantah is a big-block, that's what you're saying?

[ducatiz]

so a Pantah is a big-block, that's what you're saying?

No...  the 851 used a lot of pantah stuff.  The 906 moreso...

[brad black]

the 851 is a pantah with the cylinder studs moved apart to accept a larger bore, the gearbox shafts moved apart slightly for the 6 (not 5) speed gearbox and a different face on the cases at the alt cover.  906 had a longer crank on the alt end than the 88 851, 89 851 has the longer style crank.  it's an evolved pantah, as is everything pre panigale.

the 1989 900ss used these cases with air/oil cooled cylinders and heads.  it also had the shorter crank at the alt end until 1992 sometime.  apart from the water cooling and crank it's the same as the paso motor.  had the digiplex ignition unit too.  all 91 to 98 carb motors also have kokusan ignition.

when the crank got longer the flywheel splines also went from 6 to 16 (?) like the 851/888 motors did, but apart from that it was the same thing up until 1998, when it got injected.  apart from the small valve and 750 cam m900 motors.

early elephants were 5 speed i think and ie, later ones were carb with small valve and 750 cam heads.  that motor then went into the m900

[rorschach]

Perfect.
Thanks guys.