So I machined a peugeot cylinder to fit on a laura case. The cylinder has the same bore and stroke as a batavus laura m48 and can use the same piston setup. The following must be done in order to fit it:
1.You must dremel the cylinder skirt off by 12-13mm (leaving 13mm) and grind it about 2mm thinner. It takes a little while but it works and fits.
2.You must drill out the cylinder holes closer by at least 2.5mm on each hole. The total bolt spacing difference from the laura cylinder is 7mm. by drilling in 2.5mm you can allow a maximum of 3mm to be taken up by case gaskets. Ultimately the more you drill out of the cylinder bolt holes the less case gaskets material you can use and the better gasket seal you will have, plus the more you can bolt down the flywheel and clutch nuts without altering anything. Ultimately the best setup would be to drill in the holes by 3.5mm and leave 1mm for gasket space. It just takes forever with a common drill. but will work much better.
3. You can do the same to the peugeot head or if you drill out the holes on the laura head, that will work and is preferable given that the laura head will be matching the laura piston dome.
These specs will work with a peugeot cylinder with the intention that a polini or athena peugeot kit will also work given the same guidelines. To allow for a kit to run WELL you need to be able to put a much better carb there and enlarge the intake port. This is my next step:
JB weld the outside walls where the intake case port is so that you can grind out the inside wall. Make custom reed setup and intake/carb.
I will keep everyone posted and write this up with drawings and pictures soon.