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Discussion Starter #1
Here's the story... Apparently in my recent crash, a piece of metal got sucked into the front cylinder of my 996. As I pieced the bike back together, I was unaware of any engine damage and proceeded to ride about 300 miles before the remnants of this piece of metal finally shorted the spark plug, and prevented the bike from running.

Teardown went pretty smooth, and the damage was limited to one slightly bent intake valve and some shallow dents speckled across the piston face and combustion chamber of the head. Also, upon teardown, I found a few flaking rockers, but seeing as this is a fairly common problem, I doubt its related.

As I rebuild the motor, I plan on having all the opening rockers resurfaced by MBP, replacing the bent valve with OEM, installing VeeTwo adjustable cam pulleys, FBF hi-comp pistons, and setting the squish.

Now for the questions... I talked to my local dealer and they do not know where to get the cylinder base gaskets in various sizes other than stock. Apparently, the Ducati Performance gaskets have been long since discontinued.

1. Where can I get the needed base gaskets to set the squish on my 996?

2. What is the prefered squish measurement for a bike ridden mostly on the street, with occasional track days?

3. Is there a magic base gasket thickness that I need?

4. Will the FBF pistons change the base gasket thickness needed to properly set squish?

5. When setting the timing with the VeeTwo cam pulleys, what is the recommended advance/retard for the intake and exhaust?

As a side note, the bike is a 2000 996 BiPosto and the only current engine mods are Termi 45/50 half system and PCIIIUSB. I have access to a dyno and full mapping capabilities, but it ain't cheap so I would prefer to run it once as opposed to run it, change it, run it, change it, etc...

Sorry for such a long post and thanks for the help.
 

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You can get custom made copper gaskets at http://www.coppergaskets.us/

You may want to look for and talk to Photon as he was doing his 996 rebuild as well and he has some solid info on the process.

The guy at coppergaskets.us has already made some for 996/998 bikes so it should be easy for him to do some custom ones for your application.

I think the change in gaskets is no big deal but what would rather make it difficult is the setting of proper torque with the new gaskets ...

YMMV

Migrane.
 

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I wanted 0.2mm less squish for my 916 and had difficulty finding a 0.8mm gasket (stock gasket is 1mm), although 0.4mm were available to double up.

But I had 0.2mm machined off the bottom of the cylinders which was a cheaper option and it means I use stock base gaskets. I set the squish to 1mm which I understand is the optimum for a road bike.
 

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2. What is the prefered squish measurement for a bike ridden mostly on the street, with occasional track days?

Somewere in the region of 0.9-1.0mm are normaly ok.

I am running my 984/S4 at 0.92 and my 851/996 hybrid at 0.98 if i remember correct

3. Is there a magic base gasket thickness that I need?

I installed a 0.30mm in my 851/995 hybrid and the gave 0.98 with stock pistons

4. Will the FBF pistons change the base gasket thickness needed to properly set squish?

Maybe.

Do you need new pistons? Reducing the squish will increase the compression from some thing like 11,3 to 12,0. Advancing the inlet cams will increase the cylinder pressure even more and gives the midrange a nice boost.

Did you already buy FBF pistons? I have a feeling that they are not the best pistons to have if they did not came with a new model recently. What compression do they give?

If you want some good pistons you should go for Pistals. They are normaly supplied with two wristpins so you can get them light and nice (requiring rebalancing) or with a heavy pin so the piston weight will be the same as stock (no balancing will be required).

Some good porting would be better invested money then HC pistons I think.

5. When setting the timing with the VeeTwo cam pulleys, what is the recommended advance/retard for the intake and exhaust?

I would run some thing like 108/108. I think that the important thing is to close the inlet valve at around 60 degrees ABDC. Running 108/108 will give 58 degrees I think. If you install higher compression pistons you can not advance the inlet cams very much so you might want to run the inlets on 113 or time it to stock setting.

Jocke.........
 

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Discussion Starter #5
Thanks for the help so far.

DukeDesmo, machining the cylinders may be a good idea. I know a guy who does good machine work, so I may have to check that out. For some reason, custom made gaskets just don't sound like the way to go for me.

vij, no, I don't need new pistons, but I'm hoping this will be the only time I have to tear this motor down this far, so why not. The FBF pistons are "drop-in" replacements with rings, pins, and clips. They claim 12.5:1 compression. I have always heard Pistal is the best way to go, but I've never heard anything bad about the FBF pistons and my budget is a little limited.

Obviously, porting the heads will see a few gains, as well as cams and exhaust, but right now I'm focusing on deeper things. I understand that this setup may not be optimal, but it is, IMHO, the first step in a complete package. Porting, cams, and exhaust will all come later.
 

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I had my heads gasflowed by Chris at CJS racing http://www.cjsracing.co.uk/ (a member on this forum) but kept stock pistons.

The result was better (and cheaper) than would have been gained by fitting HC pistons, of course I did other mods at the same time that brought the cost up somewhat but I would still have done them if I'd gone down the piston route.
 

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Thanks for the help so far.

vij, no, I don't need new pistons, but I'm hoping this will be the only time I have to tear this motor down this far, so why not. The FBF pistons are "drop-in" replacements with rings, pins, and clips. They claim 12.5:1 compression.
I would keep the stock pistons if they are okay. I would do some Machining on the heads to get higher compression and save the money for later upgrades of the heads.

The real power is coming from good ports.

Jocke.........
 

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I have had base gaskets of varying thicknesses laser cut to perfection at a very reasonable cost.
Just find a company that does that sort of work, give them an original gasket to copy from and the computer controlled machine will give a perfect result.
 

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The piston brand you mentioned -. I would never fit .
I recommend the pistol R2000 . Its a perfect fit gives a beast load of compression and as a drop in gives 10hp. The other piston will be lucky to deliver 3 ponies with its too deep and wide piston pockets combined with the wrong small end width wich causes problems

If your looking to save costs take 0.6-0.7mm from the heads - reset the cams to stock specs with adjustable pullys if you can afford. You could even get very close cam timing by using just 2 stepped keys on the driven shaft . Once the intakes have been syncronised this way i have never seen the exhaust cams more than 2 degrees apart. However with keys you do need a good collection to start
 

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Why not surface grind a set of stock gaskets to the required thickness? They are magnetic, so it should not be a problem to do. It seems that it would be simpler than machining the cylinder bottoms.

Jerry
04 ST4s
 
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