Hey guys I'm new to the forum, however I've been following a lot of the questions posted here in all topics including exhaust, petcock and such. Thanks all of you guys for your experiences and knowledge.

I have a Suzuki Boulevard 2008, purchased recently from someone who didn't use it a whole lot. The bike does not have starting issues right now, and seems to have a adequate throttle.

However I noticed that whenever I throttle it a little bit during idling, the throttle is most of the times (specially when warmed up) kept at high rev and not going back to idle revs.

I have searched the forum but all suggestions are related most of the time to throttle cable, or to check carburator or idle screw.

Since nobody uploaded a video to check out the symptom I decied to record mine, so you can check the symptom out at https://www.youtube.com/watch?v=WBmgmHzD994

Let me know if you have any suggestion as to what to do.
I am electromechanical engineer with no hands-on experience in bikes however I am very familiar with engineering so you can be technical if you want.

Thank you all!

The idle on that bike is set way too low. It sounds about 600 rpm when it should be around 1400 rpm. The danger of running with too low an idle is that there is insufficient oil flow below 1200 or so rpm.

You will probably find that the hanging idle may clear with a higher idle. If not, then I’d check the carb diaphragm for a crack and while apart, clean the slide.