The idle on my BX used to be 1800 RPM from the factory, but now it is 1100 rpm and is smooth. Here is the video;
https://www.youtube.com/channel/UCsF0NLJSvjdzEnX5XGi7C9A/videos
Not an engineer but save there careers monthly and have built many cages from the county jail to a diesel dragster.
I also noticed on previous BX's that the ROPS were smaller.
The ROPS is to tall, I cut 10" off mine and now it looks right with the canopy. I'm 6' 6" tall and it still provides safety and it fits in my garage.
https://www.youtube.com/channel/UCsF0NLJSvjdzEnX5XGi7C9A/videos