Spring Calc

Below is an interactive calculator to help you choose the right spring rate for you.  

Enter in your details into the green cells to get your result. 

Average leverage ratio - this is suitable for bikes with a linear leverage curve.

Known leverage at sag - this will give you a more accurate spring rate for bikes with a progressive leverage curve. 

Don't know what your leverage curve is? Some manufacturers publish on their websites, some don't. If they don't this is a great resource - https://linkagedesign.blogspot.com/  

If your unsure of any of the sections, please refer to the Key below the calculator.

Please bear in mind that this is an indication for spring rate based on an average riding position - if you tend to load the front more, or the rear more, or if you're a more aggressive, or less aggressive rider, you may want to go either side of the result.

 

Key: 

Riding Weight - this is your weight with all your riding gear and any pack that you carry on you (not the bike). Enter the value in Kilograms. Got your weight in lbs? just divide by 2.2 to get kgs. Got your weight in stones? Multiply by 14 (to get weight in lbs, then divide by 2.2 to get kgs. Here are some examples:

200lbs   200/2.2 = 90.91kg

13stone  13x14 = 182. 182/2.2 = 82.73kg

13stone 5lbs  13x14 = 182. 182+5 = 187. 187/2.2 = 85kg

 

Bike Weight - this is the total weight of your bike, including any tool kits, spares, water bottles, etc. Enter the value in Kilograms. Got your weight in lbs? just divide by 2.2 to get kgs. Got your weight in stones? Multiply by 14 (to get weight in lbs, then divide by 2.2 to get kgs. Here are some examples:

200lbs   200/2.2 = 90.91kg

13stone  13x14 = 182. 182/2.2 = 82.73kg

13stone 5lbs  13x14 = 182. 182+5 = 187. 187/2.2 = 85kg

 

Chainstay Length - you can get this from your frame manufacturers geometry chart. Enter the value in millimetres. Only got inches? Just multiply by 25.4 to get millimetres. Example:

17inches  17x25.4 = 431.8mm

 

Wheelbase - you can get this from your frame manufacturers geometry chart. Enter the value in millimetres. Only got inches? Just multiply by 25.4 to get millimetres. Example:

50inches  50x25.4 = 1270mm

 

Wheel Travel - you can get this from your frame manufacturers specifications. 

Enter the value in millimetres. Only got inches? Just multiply by 25.4 to get millimetres. Example:

6inches  6x25.4 = 152.4mm

 

Shock type - select your shock from the list. 

 

Shock Stroke - you can get this from your frame manufacturers specifications. 

Enter the value in millimetres. Only got inches? Just multiply by 25.4 to get millimetres. Example:

3inches  3x25.4 = 76.2mm

 

Desired Sag - enter in the percentage of sag you would like. It's best to start with your frame manufacturers recommendation. But if you have a preferred amount, enter what you would like. If you don't know either of the above - as a general rule of thumb: XC Trail 28%, All Mountain/Enduro 30%, DH 33%. If you're a more cautious rider, you may want to increase that number, or if you're a more advanced and aggressive rider, you may want to decrease that number. 

 

Leverage Ratio at Sag - enter in the leverage ratio value of your bike at the sag point you're after. Some manufacturers publish this data on their websites, some will supply if asked, there are a number of bikes posted on Linkage Design's blog (a great resource for free).