Atleast 191/2' shock sounds like ur guessing on that.get a stand must be 12inches high put the front of the quad on it with the tires on take off the shocks and let the front end drop ur tires must hit the ground when they do take a measurement from center to center of the mounting holes ( top shock mount to center of ur a-arm bolt ) that will tell u the length of shock you need hope that help you if you didn't know for sure the exact length you needed