June 2006
The first thing to do was to bore the crank case from the standard 100mm , to 102 mm to accept 955 (96 mm bore) cylinders. I was looking around to find some one that could do that for me. I called some tuning shops in town and all said no worries. Just give it to us and we will sort it out. We will send you the bill in the end and it will all be good. When I asked them how much they know about Ducatis and Ducati crank cases they all said that it is just another crank case. They are all the same.
I was not fully happy with this answer so I checked aroung and found Schnyder Corse in Schänis east of Zurich in Switzerland. I was talking to Edgar. Nice guy. He said that they do this stuff regularly and it would be no worries. He actually said that if I want a 955 case I could just come and get one straight away as they still had a few since there 955 racing times. I explained that I had a monster and not a standard 916/955. We decided that it would not work due to the different swing arm so my case had to do the job.
I went over to Edgars shop and we discussed my plans. I showed him my cylinders, pistons and my single Pankl H-beam Ti rod hoping that he would have another left over for me.
"Ex Foster Crash Juni 97 Belt" was the message written on the rod and now it was not a coded message any more.
Edgar then went over to my 955 cylinders and commented that they looked old and tired. I would not trust them if I were you he said. On top of that they require 102mm crank case bore. If you do that the crank case will crack sooner or later he said so it is just stupid. Okey. Lost again.
Finally my nice FBF Viseco pistons. “American pistons. Americans do brilliant things in steel and other materials but they do not know how to make good quality pistons that can take some beating in a Ducati. I have tried this ones and they will crack here, and here and here too. Lost again
Okay. Now I was feeling very stupid. Edgar presented how he would do a project like this and he also showed me his 1100RS. It might sound like a BMW but it is a 996 with 100 mm bore and 70 mm stroke equal’s 1099cc. I realized that I had see the light and come to the right place and that I was actually talking to the twin brother of the guy that created Jesus and all this other big stuff in the world.
Bore the crank case in steps 101,5 and 101mm instead of 102. This was tested very successfully on the Schnyder Corse tuned bikes/engines that were regularly beating the official bikes both in speed and reliability in the early and the mid nineties. This will reduce the risk of crank case cracking. Cylinders were no problem as Schnyder still had some 955 on the shelf from the 955 racing days.
Omega race pistons with 21 mm wrist pin and cutout for 37/31mm valves. Same cylinders and pistons as Andreas Meklau was racing in the 90;s
Carrillo rods designed/reinforced By Schnyder Corse with stronger bigend and bigger bolts then normal.
900SS crank shaft lightened a bit, a little knife edged and balanced.
Step 1. Penetrant check / inspection of crank case to check for cracks before any new horse powers are installed.
Step 2. Boring case to give space to the bigger cylinders.
Step 3. Take away all sharp edges, rough material in the crank case and anything that creates load concentrations that potentially can start a crack in the crank case.
Step 4: Measure the size on crank shaft main bearings, main bearing holding bushings and the bore for the main bearing holding bushings in the crank case. Calculate what size of main bearing holding bushings that should be used to avoid bearing/bearing holding bushing rotation and at the same time not overloading the crank case.
One thing that I noticed was that the locating dowel for the cylinders were located in a different position an a S4 compare to a standard 916 case. This created a problem. How do you know accurately were it should be located and how do you drill the hole in the right position? Edgar sorted that one easy as he just copied the position of the dowel on a 916 and entered the datas in his CAD what ever it is thing and the CNC machine was doing the job almost by it self.
