I'm a long-time motorsports obsessive, but I've only recently gotten more interested in MotoGP. I followed the 500cc class back in the 1990s, but lost some interest after seeing Rainey's accident and have only casually watched since.

Some of you may know my analysis work at f1metrics. I have recently been considering some historical analyses of MotoGP/500cc. There are many similarities between two-wheel and four-wheel racing categories, including the basic data structure (finishes and DNFs, with points awarded for some positions), not to mention some individuals in common. But I also need to be aware of some of the key differences.

If anyone knowledgeable could help me with the following questions, I would much appreciate it.

(1) How do differences in team performance typically compare to differences in rider performance? In some categories, such as F1, team performance differences are huge, whereas in other categories they are quite small.

(2) How exactly do constructors work in MotoGP/500cc, and has this changed over time? In F1, the chassis and engine can in general be constructed by different parties, although works teams also exist (i.e., teams that make both chassis and engine). In F1, there are also cases of different teams running the same engine-chassis combination in the same season. That also seems the case in MotoGP, with both works teams and satellite teams. But what about the open category, which seems new?

(3) Related to that, if two riders are both on say a "Honda" in the same year (before the open category existed), is it fair to assume they usually had similar equipment?

(4) How has bike reliability changed over time? Was there ever a period where bikes were much less reliable, like F1 cars in the 1980s?

EDIT: Thank you for all the amazing responses!