Hello I have a LetusXL and was wondering if pre-ai lenses will work correctly on it?

Thanks

My approach to this would be to take your Letus-Nikon mount to a camera store and try a non-AI lens on it. Some of the older lenses will ride high on the mount or bind where there is a rim protruding rearwards from the aperture ring.

The genuine Nikon mounts have a clearance relief cut out of them where this rim goes. Some 35mm adaptors with their own flavours of Nikon mounts do not have this relief cut deep enough.