Should there be a cap here?
 

I never had a non Shimano crank so I am not sure if there should be a cap on the non drive side crank? I think the crank is a 3D Rotor...

https://cimg9.ibsrv.net/gimg/bikefor...91711a0b9d.jpg

There are lots of cranks that have a wide open spindle on one side or another. generally speaking, that wide open cavity has nothing to do with anything that might damage bottom bracket bearings. If the crank and bottom bracket are well designed, this should be nothing to worry about. just because it doesn't look like a Shimano crank does not mean that it will be a problem

The easiest way to tell if there should be cap there is to see if it's threaded where a cap would go, if so then yes there should be a cap there, if not then there is no need for one.

Think of the grams you’re saving by leaving it off. :lol:


-Kedosto

That's a Rotor 3D30, and that's how it's supposed to look. The 3D30 INPower has a door there.