How many years from the year the motorcycle was built should you hold onto it before the parts become too expensive

For example I was interested in buying a 2006 Honda CBR600f4i until I looked up the price of the fairing pieces. Just a small piece of the fairing was over $600. Of course they charge that price because they want you to buy a new motorcycle.

Read more: How many years from the year the motorcycle was built should you hold onto it before the parts become too expensive