[Guest]

I have been trying to find sites to help explain if this mod is possible but am having no luck. Does anyone know if this is possible. I have a 2000 M750 and would like to put heads from a M900 or 900SS on but I am not sure what the out come would be. Anyone out there have experience with this.

 

[Speeddog]

IMHO, These guys are some of the sharpest tools in the shed...

http://www.moto-one.com.au/performance/duccapacities.html

 

[Guest]

This site is awsome. Thanks speeddog

 

[chris]

I gave my thoughts about it in this thread: http://www.ducatimonster.org/cgi-bin/yabb/YaBB.cgi?board=tech;action=display;num=1083098902

 

[Guest]

i'd never considered the v2 - w2 thing, but that's good info. i'll try to remember to put that on the site, with chris as credit for it.

i don't think the 900 heads will fit because the stud spacing is different - bigger on a 900 (same as 4v) plus the chambers will be bigger, requiring very high comp pistons to get equal or higher comp. not sure how much bigger, but bigger anyway.
they all have flat top pistons std.

you can get 42.5/37mm valves in a 750 on std seats afaik, and that would help greatly. 900 cams will go in, will/may need oversize shims or just get 900 length valves. or get 900 valves and have the heads cut down a touch as reqd.

maybe the vee two 900 torque cams will work well - the 800 has 900 valves and shorter duration cams and it makes a heap more power than a 750. these will definitely need longer inlet valves as the base circle is smaller than the std 900 cam which is smaller than the std 750 cam.

but you'll need big valve releifs in the pistons - those cams have a lot of lift at tdc.

think i'm getting off the question.

 

[chris]

Hi Brad,

I didn't know first hand about stud spacing on 750 but a couple of people have confirmed that 750 uses same spacing as 900 (which I just casually measured to be 75x95 mm). This is what leads me to believe that the crap m900 heads are literally left over 750 heads. Which 4V have this spacing? 851/888 ... oh right, 748 and 916 do, too, but they have bigger well for the cylinder. Then 996 has bigger spacing...

I got ST2 cams for my project 966. How do you think 800 cam compares to the rest of the 2V cams out there? (Hmmm, need to read up on your site again... you may have already answered that!!!)

I really enjoy how the 2V Ducatis are like what we Americans call "small block Chevy" in that many parts can be swapped from all different displacement families to make fun new configurations. What I'd like to know is what they did with the 1000DS motor to get 71.5 mm stroke? Did they relocate the timing layshaft? Or is it in the traditional location and then make the rod journals in the crank smaller?? Too bad Ducati doesn't sell a "crate motor" of 1000DS complete with long intake manifolds and the old style carbureted inductive pickup coils and 3 phase regualtor ... all as a bolt in package!

 

[chris]

Ah just found the cam page... http://www.moto-one.com.au/performance/duccamspec.html Looks like either SSie or ST2 cam are the way to go unless one gets V2 with a little more lift. Given how crap the US dollar has been, I'll stick with Duc OEM for now.

 

[Guest]

i thought the stud spacing was different, but i could be wrong. i'm not sure if i have actually ever measured it. maybe the late - '99 on 600/750 run the big spacing.

 

[Speeddog]

I'd like to slip one of those 61.5mm M1000 cranks into my S4, that would be be a nice bump from 916cc to 992cc. That and the wide ratio tranny...
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M1000, M900 and S4 all have different part# rods and rod bearings.