I don't have any Moki's any longer so I don't have a way to compare them back to back. However, the 1.8 on their website looks identical to several photos I have of my 1.8.

Like any other engine on the market, it's safe to assume that the factory has certainly made changes over the years to the 2.1. We know they've experienced cost issues and exchange rate problems so perhaps this may have led to some changes that you've observed? What's different?