[nanard289]

Hi Blykins

Coil over adjustment is a frequent problem for everybody. Your choice for a 13.25" shock can be OK, but this characteristic is not enough. You have to define the requested shock stroke you need according to your maximum and minimum shock displacement. If you need for example a 5" for total stroke, it means that your shock absorber shall be 8" fully compressed and 13.25" fully extended (remember that the last .25" are not used). Then, you have to define the spring load characteristics. First you have to measure the total spring length (of course, you know the internal diameter). So, you have to check in your shock fully extended the available space between both spring retainers (the low one shall be unscrewed at the lower place). I suppose you measure 8.5". Then you substract 1/4" (that you do not need) and the total spring length shall be between 8 to 8.25" (regular length). It is a common approach to have between 1/3 - 2/3 (street use) to 1/2 - 1/2 (track use) as setting ratio for the "compression stroke" and the "extension stroke". For this example, the compressed part could be 2" and the extended part 3" for a mixt use. That means if the suspended load at the front wheel is 600lbs at the shock axle, you have to find a 300lbs/inch spring to have the correct 2" compression strock (stand by position). Finally, you have to check that this spring of 8" total length and 300lbs/inch is able to have a 5" compression with some gap remaining between each turn. When you install the spring in the shock, you will unscrew the lower retainer by .25" to have a free space without spring compression and to facilitate the shock installation (remeber that you have only 13" between both fixing points). Hope these informations could help you. All the best for your project.