[Renni]

I have original diesel enfield and it feels quite slow.
Have heard possibility to change 500cc sylinder, but do not know where parts can be ordered cylinder, piston, gasket ?

Does anyone know which Lombardini engine the original 325 is ? and/or which ~500cc cylinder would fit ?

Br,
Renni

[Bilgemaster]

How's your German? The German Royal Enfield Forum over at https://www.royal-enfield-forum.de has lots of members with diesels. A quick search of that Forum for "Lombardini" revealed several hundred hits. You may or may not need to be a member over there to view these search results: https://www.royal-enfield-forum.de/search.php?keywords=Lombardini&fid%5B0%5D=7

As for "Lombardini", it seems that brand is now owned by Kohler. Here is the website of one of their distributors in Germany called "Motoren Frech" that comes recommended as "really nice folks" ("sehr nette Leute") on that German Forum for parts: http://www.motoren-frech.de/ERSATZTEILE/KOHLER/kohler.html . Their direct general contact  email is: info@motoren-frech.de