Kia Rio crankshaft pulley, something unusual ...

Hello friends, I'll tell you what happened to me. I replaced the timing belt on a Kia Rio 1.5 petrol 16-valve, everything seemed fine, but when I started the vehicle, after a short time it was running I heard a small clicking sound... and I noticed that the crankshaft pulley, which is actually made up of two parts in one (that is, one pulley for two belts, each belt line of a different diameter), was the source of the clicking sound. To my surprise, the sound was coming from the pulley where a spark (a huge spark, bigger than a spark plug) was being produced between the two pulley tracks. When the engine runs without the auxiliary belts, the spark disappears. I've managed to eliminate the spark by connecting the pulleys with a gap. My question is, could someone give me a reason (besides static electricity) why this kind of spark might occur? I can tell you that even several official service centers haven't encountered this problem. Thanks a lot, friends.

In my entire career as a mechanical engineer, I'd never seen that problem, to be honest. The friction between pulleys could cause it; that is, the rubbing of two different metals can indeed cause a spark. But for that to happen, one part would have to slide over the other. But nothing came loose or anything, so the solution is perfect, since in some H100s or Gallopers the damper is designed like that with a flange in between.