900SS engine retrofitting oil cooled cylinders onto an air cooled engine

[FrankenDuc]

Alright, so I'm just starting to get into an engine build with an '02 900SS engine as a donor (V2 heads), and I'm planning on retrofitting a pair of older oil cooled cylinders.  My thought is cylinder temps will be more well controlled with the oil cooled jugs (I've got a good set of air cooled and oil cooled jugs and pistons, so I could go either way..)

Any thoughts, positive, negative?  Some oil galley won't line up, or that sort of thing?

A specific area of concern I have is the oil pressure, does anyone know if the oil cooled jugs require a higher flow oil pump?

Cheers, and thanks in advance!

[Raux]

huh?

I thought all the jugs were oil cooled, the diff was the external lines vs. the internal channels.

[FrankenDuc]

'99 and up doesn't have the oil jackets on the cylinders (as far as I know... the later cylinders I have I'm sure do not, it's all larger air fins and straight oil galleys).

mod'ing the alternator cover to take the oil returns is easy peasy (the later castings just happen to have large blanks where the old model returns went, so quick drill and tap..)

Mostly concerned that the older models may have a higher flow oil pump.  Guess I could get one and do a side by side...
Or, just build it and see if they come 

[ducpainter]

'99 and up doesn't have the oil jackets on the cylinders (as far as I know... the later cylinders I have I'm sure do not, it's all larger air fins and straight oil galleys).

mod'ing the alternator cover to take the oil returns is easy peasy (the later castings just happen to have large blanks where the old model returns went, so quick drill and tap..)

Mostly concerned that the older models may have a higher flow oil pump.  Guess I could get one and do a side by side...
Or, just build it and see if they come 

According to a post by Brad Black the later bikes have a higher pressure pump due to different gearing.  http://www.ducatimonsterforum.org/index.php?topic=61594.msg1138485#msg1138485 not sure about volume

I think they allowed for it with the banjo bolts. You need to use the correct size orifice in the banjo bolts to control flow with the oil filled cylinders.

[FrankenDuc]

Many thanks Ducpainter (and Brad Black)! 
I'd seen this post before, but totally glossed over Brad's key point...
different gearing same pump means higher pressure and (given same restriction) higher flow, so easy answer!

For some reason I was under the assumption that the oil jackets were fed by the low pressure returns from the heads (those little holes in the heads that you're best to stick a 5mm bolt into while you're adjusting the valves, lest you find yourself trying to fish a closer retainer collet out of the hole)...

If the jackets are fed from the high pressure side, then flow restriction is absolutely essential.

Don't know why I haven't done this already (uh, lazy...), but I'm going to have to go blow some air through the oil passages and figure out exactly what goes where.

[MonsterHPD]

I had a look at this when I switched heads and hi-comp pistons from our "rain bike" (900 SSie, 1999 or 2000) to my 2002 M900, but don't really remember much detail any more. I vaguely remember the oil jackets as beeing nothing more than an expanded cavity where tha air-cooled cylinder has a straight oil passage (pressure side).

In the end I did not look into it any more since I kept the M900 air-cooled cylinders and took the pistons and heads from the SSie. Reason for this is a very annoying difference between the air-cooled and oil-cooled cylinders: the locating dowels between cylinder and cases are in different positions (90° difference).

Both engines run very well, despite one set having appr. 30K and the other 60K, wear differences were not measurable, and the smooth cylinder coating assures there are no mating problems to the different sets of rings. Compression good, no oil consumption to speak of in any of them     

[brad black]

locating dowel change is 2002 onwards.  post 98 cylinders have internal oil returns, which i think means they pump the hot oil through to the heads or maybe out through small holes in the oil drain back cavities.  never checked.  2001 ss has the air cooled cylinders.

98 manual shows it returning from the cylinder jacket somehow.  not sure where physically.

2001 is the oil pump drive change.  they also have larger internal feeds and better piston oiling via the lh cases.  although earlier engines have the drilled screw too, just none of the manuls show it ime.  the oil pump relief was in the cover by then too, some 1999 - 2000 engines still have the relief piston in the cases as well, but it has a big spacer to hold it shut.