If you order the correct 412's for the America, you'll have a choice of spring weights....standard and heavy duty....according to your personal weight, solo/passenger, luggage. Choose wisely cause you could make the wrong choice and it'll cost you more to correct the problem. Don't ask me how I know! If I could do my choice over, I'd go with the 440's, or probably better yet, the Hagon Nitro's. Ask Staffo!
http://www.progressivesuspension.com/pro...mp;modelID=1034
