We purchased two adult sized Monster Moto mini bikes in Nov. 2017. The clutch on one of these emitted a loud noise when ridden. We were asked to send in a video of the problem and Monster Moto responded quickly saying that the clutch needed replacement. They also stated that a new clutch would be shipped out shortly. It took over a month, and several follow-up calls to get the replacement clutch. It seems that there is a lack of communication between Monster Moto's customer service and their shipping department. We did finally get a replacement which we appreciated.