PS-8975-DRAG (Double Adjustable) TECHNICAL MANUAL Main Office 150 Franklin St. • P.O.
PS-8975-DRAG (Double Adjustable) 2010/2011 Table of Contents: Introduction Terminology Getting Started Setting Ride Height Adjusters Setting Adjusters Adjustment Range (general) Adjustment Range (rebound) Adjustment Range (compression) Factory Settings Track Tuning Assembly Parts List Warnings Troubleshooting Technical Support p.3 p.4 p.5 p.6 p.7 p.8 p.8 p.9 p.10 p.11 p.12 p.13 p.15 p.17 p.17 p.
PS-8975-DRAG (Double Adjustable) 2010/2011 Introduction Thank you for purchasing Penske Racing Shocks 8975 Series double adjustable shock absorbers. The 8975 Series is the latest addition to Penske Racing Shocks successful product line-up. The most economical multi-adjustment shock, the 8975 Series utilizes standard Penske Racing Shocks parts already known for their quality and repeatability. Every Penske Racing Shock is 100% hand built and dyno-tested for the best performance and customer satisfaction.
PS-8975-DRAG (Double Adjustable) 2010/2011 Terminology: Compression Adjuster Body Ride Height Adjuster (coil-over applications only) Spring Shaft Bearing Shaft Spring Retainer Rebound Adjuster ( Clevis 4
PS-8975-DRAG (Double Adjustable) 2010/2011 Getting Started: Shocks are sent from the factory at recommended start settings for the application in which they were ordered - pressurized and ready to go. Some basic tools needed to adjust the 8975 Series shocks are: 1.) Allen Key (3 mm): to secure ride height adjuster after setting ride height with springs. 2.) Pre Load Adjuster Tool: to make ride height adjustments to spring perch. 3.) Allen Key (5/32”): to make compression/rebound adjustments. 1.
PS-8975-DRAG (Double Adjustable) 2010/2011 To Set Rider Sag: Shocks will arrive from the factory with ½” of spring preload. Rider sag must then be set AFTER installing the shock on the bike. After sag is set, tighten the 2 Allen screws (3mm Allen) in the spring perch to prevent loosening. Avoid over-tightening – nip-up gently to avoid damage to the body threads. STEP 1 1. Without a rider on the bike, have an assistant lift the rear of the motorcycle until the rear wheel is off the ground slightly.
PS-8975-DRAG (Double Adjustable) 2010/2011 Adjusters: There are 2 external adjustments that can be made while on the bike. Compression Adjuster (5/32 ALLEN KEY) - This is located in the body cap and offers 48 different positions of compression adjustment. The range of adjustment depends upon the relative stiffness of the compression stack in use. A typical “B” compressions stack will have about 150 lbs of adjustment range.
PS-8975-DRAG (Double Adjustable) 2010/2011 To Set Adjusters: 1.) Turn knob or screw clockwise to full stiff. 2.) Turn adjuster back counterclockwise to desired settings. This is typically shown as a negative (-) setting. Example: Compression -5 clicks, Rebound -10 clicks/sweeps. 3.) During discussions on handling, if you are instructed to “soften rebound by 5 clicks” that would mean adjust the rebound counterclockwise by 5 “clicks”.
PS-8975-DRAG (Double Adjustable) 2010/2011 Adjustment Range: REBOUND The rebound adjustment range is extensive, accommodating many bike and track conditions. The adjuster is most effect in the 0-10 in/sec velocity range of the shock. This is because the rebound adjuster is a direct bypass to the main piston and shim configuration; therefore it has a greater overall effect on damping.
PS-8975-DRAG (Double Adjustable) 2010/2011 Adjustment Range: COMPRESSION (48 Clicks) The compression adjuster works differently in that it is affected by displacement of the shaft. The more oil that is displaced, the more effective the compression adjuster will be, or the more the rider will feel it. On very small bumps, it may take more “clicks” on compression for a rider to feel a difference, where on rebound it may only be 1 or 2 clicks to notice a difference.
PS-8975-DRAG (Double Adjustable) 2010/2011 Factory Settings: Adjusters: Typically, adjusters will be set in the “midrange” of the damper when arriving from the factory. This may be different depending on specific set ups. Precise settings will be documented on the build sheet and/or dyno sheet. Gas Pressure - This can vary from 50 psi to 200 psi, depending on the application and setup. Generally, higher compression damping will necessetate higher gas pressure.
PS-8975-DRAG (Double Adjustable) 2010/2011 Track Tuning (GENERAL): Compression Adjuster: This adjuster is typically used when looking to improve the bike over bumps. If the bike is hitting a certain bump that is causing it to “unload” the tire, simply soften the compression adjustment. This will allow the shock to absorb the bump, keeping the bike more stable and making it more controllable. Closing the compression will slow the weight transfer of the bike.
PS-8975-DRAG (Double Adjustable) 2010/2011 Assembly: 46 47 19 13 20 60 21 62 61 56 48 39 50 35 49 37 34 38 36 52 59 2 58 57 4 33 32 13
PS-8975-DRAG (Double Adjustable) 2010/2011 40 10 2 52 45 51 53 54 55 44 41 42 43 6 3 9 8 10 7 12 11 18 13 17 14 16 15 5 29 22 30 28 21 27 20 26 47 23 31 19 25 14 24
PS-8975-DRAG (Double Adjustable) 2010/2011 Parts List: KEY 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 PART NUMBER BD-75XCO RR-06 BC-75TV-DA OR-2133-B CO-75HV PI-75HV-3PORT OR-2029-B VW-120004-625 VS SC-75HV-DA VW-75020-625 MR_73 OR-2008-V PI-75-DA OR-2008-V OR-4221-B NE-75X-DA RS-73 BA-093-ST SP-36 FT-75X-DA VW-75-DA OR-2011-B OR-3MM X 1.5MM-V SC-75-DA IU-75NV OR-2010-B SC-75 OR-3.
PS-8975-DRAG (Double Adjustable) 2010/2011 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 SH-75AX JT-RDHSNG JT-76POP RR-05 JT-76HAT SP-15 VW-99 CL-5450CL-H OR-2009-B MR-ROD NE-76 OR-2007-B VW-75020 PI-XX005 PB-55 OR-2028-B NT-02R SR-8975-WR RH-83XXX SC-M6M8-N BR-37 BU-04-BZ SC-30 RR-5206 SHAFT, 7500 ADJ JET, RD STRAIGHT THRU JET, POPPET RETAINING RING, .250 INTERNAL JET, TOP HAT SPRING TOP OUT PLATE, 1.375 X .
PS-8975-DRAG (Double Adjustable) 2010/2011 Warnings: It is not recommended to run lower than 50 psi in Penske Racing Shocks Motorcycle shocks, depending on piston and shims being used. Lack of nitrogen pressure could result in cavitation which can result in loss of immediate damping and rider feel. It is also not recommended to run more than 300 psi. This could result in stress fractures in main mounting components, which could result in failure of shock.
PS-8975-DRAG (Double Adjustable) 2010/2011 Technical Support: 8:30 AM – 5:00 PM (EST) Penske Racing Shocks – Technical Center 150 Franklin Street Reading, PA 19602 United States 610.375.6180 www.penskeshocks.com Rev.
