The Öhlins STX36D and STX36P Blackline are a classic monotube design, featuring all the classical Öhlins qualities delivering top notch ride comfort and performance for your bike. Available in dividing piston or piggyback versions, depending on application, it can also be specified with a number of different damping adjustment options with or without length adjustment. They are designed for Harley-Davidson and custom bikes with twin shock absorbers.
Type: Emulsion vs Gas
The key here is that there is no wrong choice – both types offer a significant ride upgrade over that of the stock suspension. The entry level Öhlins suspension is an emulsion styled suspension. This means that the shock oil and gas are allowed to mix together. The upgrade to this is a gas styled suspension which separates the gas from the shock oil using a floating piston. This chamber can either be internal or external to the shocks.
Shock Length & Adjustable Length
Yet again, there isn’t a right or right choice. Some riders may want to maintain their factory ride height, and selecting the appropriate length in order to do so would then be important. Other riders may want to increase the stock ride height or lower from the stock ride height. The key here is to know your factory ride height in order to select the appropriate shock length to fit your needs. Some of the Öhlins rear suspension line allow for some length adjustability as well. In most cases however, you would have a maximum adjustability of only +/- 10 mm (0.4 in) and therefore isn’t a replacement for selecting the correct base shock length to fit your needs.
Reservoir Location: Internal vs External
For a gas based suspension, the gases are separated from the shock oil by a floating piston. This chamber can be located internally on the shock, or remotely separated from the shock. For standard street riding, most riders wouldn’t see much different in overall ride quality, however for more aggressive riders may prefer an external gas bladder which helps provide a more consistent riding experience.
The stroke is a measurement of how far the rear shock can compress. Have you ever “bottomed out” your suspension? This means that you have maximized the rear suspension’s travel. With all things being equal, more travel is usually a benefit.
Compression damping (also commonly referred to as bump damping) occurs when your motorcycle’s wheel comes into contact with a bump in the road and the shocks compress. Compression damping regulates the force required to move a shock through the stroke / travel. Typically, compression damping is configured more firm for a Harley-Davidson as it is an on road vehicle and unwanted “bobbing” is minimized this way.
Rebound damping occurs as a result from compression. When your shocks have responded to a bump in the road by compressing, the rebound damping is response of the shock to extend back to its starting position. If rebound damping is adjusted too plush, then your rear wheel would lose traction with the road as it fails to respond quickly enough to keep your tire on the road. If rebound damping is adjusted too stiff, this would result in the motorcycle’s chassis responding to the bump. Although subjective, somewhere in the middle provides the most comfortable ride and greater feeling of control.