Put your Make, Model and Year into the Red Bar at the top of this page and your bike will pop up. There should be a box under the name of your bike which says "calculate spring rates". If you then type in your weight (plus the weight of your riding gear), you should get the ideal spring rate you need written underneath for both Fork Springs and Shock Springs. Please note that this spring rate is just a guide; if the calculator says 5.5, then a 5.4 or a 5.6 is just fine. It is a ball park figure. If your bike doesn't yet have the "calculate spring rates" box under the title, then it is one of the thousands of bikes we don't have enough accurate info about yet and so haven't added to our database. We can still get you some springs that will suit - we have thousands of variations of sizes and rates - and we can get custom made springs if we don't already have one in stock. Give us a call and we'll organize some for you.