All shock absorbers look about the same, but are application-specific in different lengths.
You can lower the front and the back of a Harley. Numerous aftermarket vendors sell “drop in” fork lowering kits that will lower your front end. But lowering the front end decreases ground clearance, which means your bike will no longer — barely — clear that parking lot speed bump. Getting hung up on that bump will damage your bike. Since this is an 883 Sportster, usually an entry-level Harley, a better place to begin might be to slightly lower the rear end by installing shocks that are one inch under stock length. Your seat will be lower, and an entry-level biker can do it himself.
1. Raise the Sportster to fully upright and level by slightly raising the bike on a motorcycle jack, by driving the front wheel into a motorcycle chock, or by clamping the front wheel upright in a motorcycle clamp.
2. Unbolt the lower right shock mounting bolt that connects the old shock absorber to the frame. The bolts on Sportsters shipped after 2005 come off with an Allen socket. Earlier models unfasten with a deep well hex socket.
3. Remove the bolt, nut and washer. Remove the top mounting bolt on the right shock and save all the hardware.
4. Remove the left shock by repeating these steps.
5. Spread three or four drops of thread locker over the screws of all the mounting bolts with your finger. Bolt the new, 1-inch-under-standard-length shock absorbers into the same holes with the same bolts that held the original shocks in place. Use a torque wrench and an Allen or deep well hex socket to tighten the bolts to 48 foot pounds of torque.
6. Lower the jack or remove the bike from the chock or clamp. Push the rear end of the bike down and let it rebound up to be sure that the new shocks work.