Warming Up Bikes Issues. The Rpm Is Not Stable.

I was having this weird issue and I was hoping someone can chime in and enlighten me about this.

Usually bikes require a few mins of warming up the engine. My issue is the sound of the engine is not consistent, or smooth all around. I don't know how to explain it but the RPM usually go up and down ranging from 1400 rpm to 1200 rpm during the warm up. And you can really hear how the engine kinda hit a low note then hit high note then a low note and go on. It usually keeps going for a few mins for the engine to go stable. When the temp reaches around 60C then engine sounds very smooth. So I think it's more of a warming up issue? I'm not so sure. I do know it didn't behave like this when I first got the bike.

I've been to every Ducati workshop but none of them have any idea. Spark plugs were replaced. Air filter was just cleaned. If anybody have any idea what I should be looking at, I would appreciate it.

Thank you.

P/S: It's a Hypermotard 950 2020.

P/S2: Also, just to add in a few info, sometimes the bike dies on it own while running in idle. I usually have to give it some throttle so the engine can be started. All of this only happens with cold start. Once the bike warms up, there is no problem whatsoever.

 

I have the Termignoni full system exhaust installed at the local Ducati dealer, together with the map provided by Ducati so it's pretty much stock in a sense. No personal modification in that regard.

And no, I don't think my bike has a stepper motor.

 

Just a quick update. It turn out to be valve clearance problem. The thing is I'm at 19,000km and I'm not due for valve clearance check until 30,000km. According to Ducati, Hypermotard 950 has a 30,000km valve clearance check interval. My local dealer did not check the valve clearance at 15,000km because that wasn't on schedule. After changing a few shims, the bike starts like new .

 

I thought so as well but nope, not under warranty.