Welcome to the forum. Stick with a reputable dealer and shy away from the E-bay sellers. You want good after sale customer support for your Motorized Bicycle kit. Check the dealers you see advertising here on this forum. They are all proven and reliable. Have fun and ride careful. Let us know where you decide to purchase you engine kit from and how the service was.
Age and Treachery Will Always Triumph
Over Youth and Skill & "Charlie Don't Ride"