Shock Absorber Type 643 QRR - IDM Preload Adjuster:Mechanical (X-PA) These have been replaced by

These have been replaced by progressive fork springs

– Radial-piston design with progressive shim stack

along with oil and recommended settings

Harley-Davidson Nightster RH975 — Compact

Shock Absorber Type 643 QRR - IDM Preload Adjuster:Mechanical (X-PA) These have been replaced byIDM race replica shock with finned reservoir. Specially developed for IDM Superbike competition, this shock uses an integrated finned expansion reservoir for superior oil cooling and a constant damping curve. Our racing teams development work feeds directly into the rider specific setup a true race replica shock. Features: X PA spring preload adjuster: stepless 15 mm range Ride height adjustment: shock length 5 mm Adjustments: high low speed