Went to the dealer today and found out (from a book he pulled out) that none of the 550's have 630 chains (I believed that it only showed the 750's having them). The books showed that the 550's have 530 chains.
530 x 110
Front 15
Rear 50
Should I change the gear ratio for a long distance trip?
It all depends on where your tack is sitting at your desired crusing speed. If you're turning 7,000RPM at 65 and you plan on cruising at 75-80mph, you may want to step it up a bit. Keep in mind that any change in ratio will directly effect your entire RPM range and gear selection. My 650 turns too fast in my opinion (plenty of power in all ranges) but as a shafty, is much more difficult to recalibrate. :?