Mittler Bros Machine & Tool 1200 User Manual

BUMP STEER GAUGE

MODEL #1200-BSG

Prior to starting any Bump Steer procedure consult your chassis manufacturer or chassis set-up publication to determine the proper Bump Steer for your race vehicle.

 Place vehicle on jack stands at desired height.  Remove left front tire/wheel and right front tire/wheel.  Install Bump Plate on Wheel Hub  Install small idler arm & roller on left pivot arm.  Install dial indicator on right pivot arm.  Place “T” Base under lower “A” frame, with pivot arms laying flat on floor.  Level “T” Base using adjustment screws at each tube end to center leveling bubble.  Position bottle jack on “T” frame under lower “A” frame.  Rotate Pivot arms up until roller & dial indicator contact arm touch Bump Plate.  Level Bump Plate so dial indicator contact arm & roller bracket align with the same

scribed mark on each side of Bump Plate.

 Compress dial indicator contact arm ½ its travel.  Rotate dial to zero on dial indicator face.  Jack suspension to simulate proper front end geometry at ride height.  NOTE: Always start Bump Steer procedure from this position.

Division of Mittler Corp.

P.O. Box 110 Foristell, Missouri 63348

10 Cooperative Way Wright City, MO 63390

1-800-467-2464

(636) 745-7757 Fax: (636) 745-2874

03-07-08 BRP

Right Front Bump Steer Procedure

Install Bump Plate on right front hub assembly and tighten 5 lug nuts. Dial Indicator on pivot arm closest to vehicle front. Use hydraulic jack to raise or lower your suspension 1” at a time. Record readings at 1”, 2”, 3” Up (Compression) , & 1” down (Rebound). NOTE: Counterclockwise dial indicator movement = Bump Out Clockwise dial indicator movement = Bump In

Change Bump Steer by raising or lowering outer tie rod connection or inner tie rod position on intermediate arm. Note: Lower Right Side Outer Tie Rod = Bump In

Left Front Bump Steer Procedure

Install Bump Plate on left front hub assembly and tighten 5 lug nuts. Dial Indicator on pivot arm closest to vehicle front. Use hydraulic jack to raise or lower your suspension 1” at a time. Record readings at 1” & 2” Down (Rebound) & 1” & 2” Up (Compression). NOTE: Counterclockwise dial indicator movement = Bump In Clockwise dial indicator movement = Bump Out

Change Bump Steer by raising or lowering outer tie rod connection or inner tie rod position on intermediate arm. Note: Lower Left Side Outer Tie Rod = Bump Out

General Rules of Bump Steer

RF is usually checked though 3” of Compression & 1” of Rebound LF is usually checked through 2” of Compression & 2” of Rebound. Set Bump Steer as close to zero as possible, if in doubt. A slight Bump Out is better than a Bump In condition The rougher the track the more critical the Bump Steer becomes.