I need a new chain since I installed my CB650 wheels and the rear gear is a 40T compared to 35 on the CM400T's rear wheel. I was hoping I could swap gears but as I found out. Everything on the 650's wheel is bigger compared to the 400's...axle, drum hub and rear gear... I got the drum covered, swingarm ground out to fit the 650's axle. I just decided to get a new chain since the old one well is old and pretty rusty and notice it already has two master links on it which I thought was kinda weird. I don't do any racing or really beat that hard and hell, I've yet to get over 65 on the bike. Do I really need an O-ring chain or a non o-ring. Do they last longer or less maint. needed? I'm fairly new to cycles so this is new to me. I suppose I could get a smaller gear but the stock chain is pretty nasty and is the 25 extra bucks worth it? 50 for an o-ring and 25 for a non.