Nope, dont worry. Kymco advise their service dealers to cut the rev limit wire on the standard cdi as part of the derestrict process so it must be ok advice if it comes from Kymco. I cut my cdi wire and got similair vibrations for a few wks but then I put an 82 main jet in for the stock 80 jet, fitted my race variator and changed the oil and gear oil and the vibration went away. Hasnt been any bother since. My gear oil level was a little high before and I now use fully synthetic oil where the previous owner didnt, dont know what was causing it but had to be one of the above, fine now anyway.