JM Racing offers suspension valving and service for all size riders and bikes.

JM Racing Suspension “How To” Set Sag:

Unloaded measurement: the first step toward determining proper suspension adjustment is to set the rear spring preload so that hte proper ride height, or race sag dimension, is achieved. For this adjustment procedure, the bike should be brought to normal racing weight- correct fuel, transmissionoil and coolant levels. The shock should be cool to the touch, as heat build up will directly affect your sag. Usint the tape measure provided, measure the unloaded dimension when your bike is supported by a works stand and the rear wheel is off the ground. Measure the distance from the rear axle up to fixed point in line with the arc of the axle. Usually the fender and side panel junction. You can put a mark on the fender, which lines up with an even number tomake it a little simpler. Write down as a dimension A (example: 605mm)

Loaded measurement: Place the motorcycle on level ground. Next measure the loaded dimension with the rider aboard, wearing all normal riding gear. Bounce your weight on the seat a couple of times to help the suspension overcome any stiction and settle a good reference point straight up from the pegs. Make sure to keep your hands on the bars, stay in normal riding position, and make sure all of your weight is on the seat with your feet barley touching the ground with enought to just keep your balance. Ask a helper to measure from the same to points (example:502mm)


-Loaded =502 mm

Race sag =103mm