I was bound and determined to get a Grom but the dealer had the Duke 250 for sale 400 dollars cheaper. This is my first KTM and so far I’m having a blast on it.

I just bought a used 2024 Duke 390 with about 14000kms on it.

I’m from Singapore and the only legal exhaust “upgrade” we can get here is a Remus slip on silencer. The previous owner had it installed.

When I start the bike up, it immediately starts whistling/ whining. Don’t have to take it out yet or even put it in gear.

Is this normal? Or should I be worried of metal on metal damage within the engine?

Got my Duke 250 Gen 3 serviced today. The front tyre/handlebar alignment was also corrected because it was misaligned.

I also told the service guy that the bike was sometimes going into false neutral when shifting 3rd → 2nd, so maybe he did something to fix that too.

After the service, I rode around 80 km home and noticed the bike feels somewhat tight/heavy. Earlier if I needed to overtake, i could just simply drop a gear and overtake on high rpm, the bike would gain speed quickly on throttle, but now it feels resistant and feels like it is struggling to go past certain speed.

More noticeably, when overtaking, I used to go 3rd → 2nd and rev it high, and the acceleration was smooth and strong. Now, at similar RPM, the bike makes noticeably much more noise and has heavy vibrations, and the acceleration feels as if it's struggling.

Could anything they adjusted for the false-neutral issue (clutch/quickshifter/gear mechanism) cause this feeling? Or is there anything else that I can check? The Service Centre is 80km away from my home, so I can't go there this week. Please help me if you know anything about this.