Brushed off my Spanish, here’s a rough summary:
Motor is Gilardoni, his mechanic says modern 250cc bikes are not built as nice as this. Only change was an aftermarket exhaust, he has the original. The motor has 25cv(?) of power, and he only rides it 4 or times a month. It’s from 1994, and not many were made since the more popular bikes were 500cc, which were not really that different. Only 2 owners, him and the older gentleman he bought it from. Original owner put on 1300 km, and the seller added the rest.