600 cylinder head differences

ibduke · 08-02-2021, 06:31 PM

Hello,
can someone please explain differences between the monster 600, 8S and S4 cylinder heads. ie cam overlap, valve size, will it fit without problems, etc

Mine is the 1999, 8S

350TSS · 08-02-2021, 07:14 PM

Not sure what an 8S is but assuming it is an 800 as in S2.
The 600 is air/oil cooled and single overhead camshaft, desmodromic operation 2 valves per cylinder
this basic engine configuration is the same for 400, 600, 620, 696, 750, 800, 904, 1000 and 1100 Ducati models, bore and stroke obviously changes.
Some models had 3 valves per cylinder (eg ST3) and some had twin plug heads (eg 1000)
The S4 (916cc) is water cooled with twin overhead camshaft desmodromic operation 4 valves per cylinder.

slob · 08-02-2021, 08:07 PM

Is '8S' the stamping/casting on your heads?

There's quite a lot of variation in valve sizes etc

Take a look here http://www.bikeboy.org/comp2vmodels.html

Kato · 08-02-2021, 10:02 PM

8S is the number stamped on the head casting indicating a 99-2001 bike pre 98/9 if I remember correctly it was K1, S4 was USA heads I think the difference was compression ratio however unsure

8S heads were also on i.e 620 /695/750/800 /620SS/750ss/800SS

The head casting is the same from 400 - 900 the difference was in the chamber and valve size and of course camshaft profile

Heads from 400 -600- 750* Monster/ SS will fit the 600 motor cams were the same until injection was introduced 2000 ?

Physically the 900 heads will also fit however I'm unsure if they will seat properly never checked so would avoid

Why do you need new ones ????

* would need to check compression / piston height
i.e the 750 had domed pistons and the heads had deeper chambers 9:1 cr
600 were flat top 10:7 cr

ibduke · 10-02-2021, 11:50 AM

I'm looking for larger valves. So the 620 wont do due to different combustion chamber/pistons.
I was thinking maybe a 750 Carburetted small valve which would still be bigger than the 600.
Looks like I'm stuck with the 600, well your never stuck I just wanted to know the options.......cheers all.

Kato · 10-02-2021, 11:58 AM

OK ...No reason why you couldn't fit the larger valves to your heads, with a little port & polish at the same time, by the time you've bought bigger valve heads, rebuilt them and messed about with compression ratio and cams it would prob work out cheaper.

Having said that you could get an entire 750 motor for around £500 and either fit that (straight swap)
or swap the internals into your 600

08-02-2021, 06:31 PM	#1
ibduke Registered User Join Date: Jun 2014 Location: Preston Bike: M600 Posts: 37	600 cylinder head differences Hello, can someone please explain differences between the monster 600, 8S and S4 cylinder heads. ie cam overlap, valve size, will it fit without problems, etc Mine is the 1999, 8S

08-02-2021, 10:02 PM	#4
Kato Dismantled Join Date: Feb 2006 Location: East Molesey Bike: Multiple Monsters Posts: 2,228	8S is the number stamped on the head casting indicating a 99-2001 bike pre 98/9 if I remember correctly it was K1, S4 was USA heads I think the difference was compression ratio however unsure 8S heads were also on i.e 620 /695/750/800 /620SS/750ss/800SS The head casting is the same from 400 - 900 the difference was in the chamber and valve size and of course camshaft profile Heads from 400 -600- 750* Monster/ SS will fit the 600 motor cams were the same until injection was introduced 2000 ? Physically the 900 heads will also fit however I'm unsure if they will seat properly never checked so would avoid Why do you need new ones ???? * would need to check compression / piston height i.e the 750 had domed pistons and the heads had deeper chambers 9:1 cr 600 were flat top 10:7 cr __________________ "Political correctness is just intellectual colonialism and psychological fascism for the creation of thought crime" Last edited by Kato; 08-02-2021 at 10:58 PM..

10-02-2021, 11:58 AM	#6
Kato Dismantled Join Date: Feb 2006 Location: East Molesey Bike: Multiple Monsters Posts: 2,228	OK ...No reason why you couldn't fit the larger valves to your heads, with a little port & polish at the same time, by the time you've bought bigger valve heads, rebuilt them and messed about with compression ratio and cams it would prob work out cheaper. Having said that you could get an entire 750 motor for around £500 and either fit that (straight swap) or swap the internals into your 600 __________________ "Political correctness is just intellectual colonialism and psychological fascism for the creation of thought crime" Last edited by Kato; 10-02-2021 at 12:07 PM..

08-02-2021, 07:14 PM	#2
350TSS Too much time on my hands member Join Date: Jan 2013 Location: Shipbourne Bike: M900 Posts: 1,420	Not sure what an 8S is but assuming it is an 800 as in S2. The 600 is air/oil cooled and single overhead camshaft, desmodromic operation 2 valves per cylinder this basic engine configuration is the same for 400, 600, 620, 696, 750, 800, 904, 1000 and 1100 Ducati models, bore and stroke obviously changes. Some models had 3 valves per cylinder (eg ST3) and some had twin plug heads (eg 1000) The S4 (916cc) is water cooled with twin overhead camshaft desmodromic operation 4 valves per cylinder.

08-02-2021, 08:07 PM	#3
slob . Join Date: Jul 2003 Location: East London Bike: Multiple Monsters Posts: 9,713	Is '8S' the stamping/casting on your heads? There's quite a lot of variation in valve sizes etc Take a look here http://www.bikeboy.org/comp2vmodels.html

10-02-2021, 11:50 AM	#5
ibduke Registered User Join Date: Jun 2014 Location: Preston Bike: M600 Posts: 37	I'm looking for larger valves. So the 620 wont do due to different combustion chamber/pistons. I was thinking maybe a 750 Carburetted small valve which would still be bigger than the 600. Looks like I'm stuck with the 600, well your never stuck I just wanted to know the options.......cheers all.