Bump Steer

What is Bump Steer?

This is when the travel of the suspension changes the tow of the tire from it's set position. The best way to tell you what it feels like is if you've ever ridden an ATV with the wrong toe in setting down the road. It wants to dart from one side of the road to the other without any warning. Just imagine this happening to you while racing and you are fatigued! Talk about a disaster waiting to happen.


How do you know if you have bump steer for sure and how much?

Take off your shocks and measure there overall length from eye to eye. Then measure there shaft length. Subtract the shaft length from the eye to eye measurement. Then align your handlebars so they are straight. Put a jack under your frame and raise it until the measurements from where the shock mounts to the frame to where the shock mounts to the A-arms is equal to your eye to eye measurement. Now take a tow in measurement and write it down. Lower the jack until the shock mount to shock mount locations equals the eye to eye minus shaft length. Measure your toe in again. If it is the same amount of tow in before you lower the quad then you have hardly any bump steer. But if they are different, then you have some bump steer!


Ok, Now that you know you have Bump Steer. How do you eliminate or at least improve it?

The easiest way to accomplish this is by raising or lowering the tie rod ends. This will be a trial and error procedure. I would recommend raising or lowering them at least 1/8" at a time so you can tell much easier which way you need to move them. If bump steer gets worse, then go the other way. The easiest way I have found is to put a washer under the tie rod ends to raise them. In some extreme cases though you may have to cut the tie rod end mounting plate off of your steering stem and relocate it higher or lower on the stem.




Site by ZRI Designs