Just a thank you and a small plug to Chris Kasel and Carl's Cycle. Just finished installing a 660 kit into the wife's 2013 Pro RMK 600. Quality parts, gaskets supplied, nice porting job, quick turnaround, and no BS sales pitch. Will be running 62g belly busters for our riding elevation, if it works half as well as I suspect, she will be one happy camper. Look for a review on performance mid November. Just a reminder to all the "late starters", this is the time to mod / build your sled for the upcoming season, not mid November...