I had a puncture on the face of the rear tire on my Vespa 250ie and replaced the tire. Had a local tire shop spin balance the tire/wheel. After less than 5,000 miles the thread was gone...I thought that strange and looked closely at the tire to make certain I didn't purchase another of that brand. While doing this I saw a great wear spot...down to the white 'string-like' stuff under the black rubber. This spot was directly opposite of the large number of lead stick-on weights the shop added to the wheel. I believe there were 10 of the lead weights.
I asked the shop why that happened, and they 'copped out' saying it was probably due to over inflation. I know that's not true.
I can only believe they did a horrible job of balancing the tire/wheel.
Anyway I have a new tire and removed all the weights (didn't ask them to balance anything this time) and found the scooter much smoother in a trial run up and down the highway.
Have you ever seen anything like this?