Be sure to let the bike warm up on the stand for a few minutes before riding. You are likely alright, I just replaced my transbelt and have over 10,000 miles on my GT. If I start off with a cold engine, or sometimes in wet conditions I get a little slip or chatter, but this is nothing to be alarmed about. With so little milage on your bike you should be fine. You can always have the Vespa dealer look it over at your next service if you are worried about it.