I am lodging a complaint against Helderberg Yamaha

I bought a demo bike off of their showroom floor (Yamaha MT-07) for R95 000.00 two months ago. It had 887km on the clock when I rode it off the showroom floor. On Friday on my way from work, the bike just did not want to ride. (There is now only 2623km on the clock) After phoning Yamaha, they picked up the motorcycle and dropped me at home. Their mechanics told me that they will supply me with a loan bike before the end of the weekend. I did not hear anything from them the entire weekend. After I finally got to work (walking for 2 hours) I contacted Yamaha and they told me that they do not do loan vehicles and that they will have to assess the bike and send me a quote. After they assessed the motorbike, it was found to be the clutch plates that snapped. I don't know that much about mechanics but a clutch plate does not just snap on a new motorcycle. I then got belittled by their staff over the phone stating that it is all my fault that there was a latent defect on the motorcycle. The motorcycle is still under warranty, yet I have to still pay for a latent defect on a two month old motorbike that is still under warranty.