Duke 250 jerking + clunk sound on throttle open/close, feels like wheel briefly resists — normal or issue?
I have a KTM Duke 250 and after around 500 km I started noticing a problem. The bike jerks during both throttle opening and throttle closing, and at the same moment it makes a clunk/tak type sound. Sometimes it even feels like the rear wheel briefly resists or slightly locks for a moment.
The issue was present even before first service. I told the service center guy and he said it’s because of riding at low RPM, but I’m managing the RPM properly and it still happens.
I also cleaned and lubricated the chain, but the problem is still there.
The jerks are most noticeable during throttle transitions, not necessarily during gear shifts.
Is this normal KTM single-cylinder/drivetrain behavior or does this sound like a chain/sprocket/brake issue? Anyone else faced something similar on the Duke 250?