Motorcycle Tech Discussion Forum

I've been digging deeper into suspension recent since I expect to get onto the track more in 2009. We've been replacing fork seals and upgrading springs and cartridge emulators from some time now. there's always more to learn. The one thing I do see a lot of, even with my own bike is fork oil .......... needs to be changed MORE often. AND it's an excuse to upgrade, even something as little as changing the weight of fork oil, if your bike wallows, the front end dives, fork oil level and preload spacers can improve your riding experience with out a lot of expense

After many miles on the my Sportster front-end it was time for new seals. This would be a good time for fine-tuning it in order to optimize performance. I decided to use Race Techs Gold Valve Emulators which would, in effect, transform my damping rod fork into a cartridge-style tunable fork.

Further improvement to the front end would come from Race Tech's High Performance fork springs. What Race Tech's Emulators do is provide the ability to adjust compression dampening by controlling the flow of the fork oil by using a spring-loaded, flapper valve that can be adjusted two ways. The first being the amount of spring pre-load, the second being the thickness of the flapper. Since rebound dampening is based on the viscosity of the fork oil, the desired weight of fork oil is the first thing to be determined. Once that is set, the emulators are adjusted by setting the spring pre-load of the valve. Increasing the pre-load will stiffen the fork during compression, but has no effect on rebound. With the Emulators in place, the most significant difference in the bike's ride is much less front-end dive when braking and cornering. This lets the suspension do what it was designed for-absorbing.