I got my 660 from heinens last month. 900+miles already this year and it runs like a top. I never got a manual with it and want to know what stock engagement is. It has a yellow/green spring primary and a silver secondary. Engagement is almost 3800 rpm but it still tops out at 7300rpm. The primary is clutched for 5000-9000 feet. I am wondering if it would be quicker with stock setup or maybe I stumbled on a R&D clutching secret??? It was a factory demo or a test sled.

What a nice machine!

Is it keeping rpm:s during heavy load as deeper powder?
Does it run straight up to max rpm:s and then stay there or does it slowly walks up to top?

I would say it gets there real fast then feels like it is over-revving it vibrates a lot by the drive axle at higher speeds.