New Bump Steer Delete (BSD) Tie rod kit for X3 is here!

[Shock Therapy]

So after quite a few miles on our X3 RS shop cars we started digging deeper into the suspension geometry and steering feed back we experienced when running the cars hard. When testing Race cars we felt that the feed back in the wheel was excessive and that the power steering was to blame. The steering power unit still might be under powered when you run a 32" tire and race the car but that isn't the only contributing factor we found. While cycling the front suspension we found that the factory front end has over 4 inches of bump steer! Wow that is a lot especially when off road teams try for zero bump steer if possible. Bump steer leads to many negatives that you have probably felt when driving your car. Here is a video we put together explaining what Bump Steer is.

In order to fix this issue we designed our BSD (bump steer delete) tie rod kit which re-locates the outer tie rod pivot point lower. This changes the geometry of the front end and gets the factory 4" bump steer down to just 3/8 of an inch. Shock loads on the front end are diminished considerably. Steering wheel feed back is nearly gone. Drive ability is much more stable and controllable. Front end parts will last much, much longer. 32" tall tires will have much less negative affect on your front end parts with the geometry fixed. The benefits go on and on. Remember EVERY X3 needs this. The bump steer problems exist in the FACTORY design. Don't wait, fix your front end with our BSD tie rod kit and see for yourself how much nicer it is to drive your X3 right away.

The BSD tie rod kit is $274.95 and uses the highest quality Teflon lined race rod ends you can buy. Kits for the base and DS are available by September 12th but the RS kit is available on our web site NOW. Thank you!

http://shocktherapyst.com/bump-steer-delete-tie-rod-kit-bsd-can-am-x3-rs/

This kit is PATENT PENDING and the pivot point location is protected.

 

[tatum]

Fantastic work fixing that much bumpsteer. That is crazy to me that they are that far off.

 

[Rynomx785]

How much bump steer does a XP have?

 

[Shock Therapy]

Honestly the only XP's we have checked are race cars with long travels. We will be cycling a stock XP Monday and let you know.

 

[CSG]

4" of bump steer measured how far from the axle centerline? Also I assume that is taking both directions into account? IE, I am assuming at some point it switches from toe-ing in to toe-ing out and you are counting total toe-change from completely stuffed to completely extended?

 

[Shock Therapy]

All toe measurements were taken 12" in front and 12" to the rear of axle center line. We count total toe change from fully compressed to fully extended. The stock system is toed out fully compressed and toed in at full droop.

 

[Bruce]

Look forward to seeing the Polaris results..

 

[motive]

Doing a little math puts each wheel at a total of 9.56 deg of change from full bump to full droop. That is most likely not split 50/50 but it does put the wheel varying somewhere around 5 degrees from strait ahead. I would have to dig deep in my notes when I analysed the XP but if I remember correctly it is not far off of that. Its just a fact of life when you have the steering rack behind the wheels, its very difficult to engineer out all bump steer while maintaining ackerman. (inside tire turns in sharper than the outer.)

I doubt Can Am was "that far off" with their design. One thing that needs to be considered is bump steer while turning. Having the wheels turned left or right changes the geometry drastically. A car that has no bump steer in a straight line can have wild bump steer while going around a corner. Making it difficult to hold your line in a turn. My guess is that Can Am compromised some bump steer in a straight line to dial out bump steer in turns.

 

[Shock Therapy]

So we cycled a stock XP today. At full compression it was .500 inch toe out. At full droop it was .500 toe in. Total bump steer 1.00 inch. This was measured with a 24" alignment bar on each hub, front and rear measurements 12" off the hub centerline. Not horrible but not close to ideal either. We are currently working on a fix for this with outer joint pin an high miss spacers using a high quality rod end in place of the factory ball joint style end. Will have results next week and a kit for it a week or two after that.

 

[Shock Therapy]

Doing a little math puts each wheel at a total of 9.56 deg of change from full bump to full droop. That is most likely not split 50/50 but it does put the wheel varying somewhere around 5 degrees from strait ahead. I would have to dig deep in my notes when I analysed the XP but if I remember correctly it is not far off of that. Its just a fact of life when you have the steering rack behind the wheels, its very difficult to engineer out all bump steer while maintaining ackerman. (inside tire turns in sharper than the outer.)

I doubt Can Am was "that far off" with their design. One thing that needs to be considered is bump steer while turning. Having the wheels turned left or right changes the geometry drastically. A car that has no bump steer in a straight line can have wild bump steer while going around a corner. Making it difficult to hold your line in a turn. My guess is that Can Am compromised some bump steer in a straight line to dial out bump steer in turns.

I agree with you that there are many things to take into consideration when designing or even just setting up front end suspension geometry. But over 4" of bump is beyond too much no matter what car your racing. I don't think Can Am allowed that to exist in centered steering position in order to help the turning bump numbers. If it were 1 inch of bump I might agree with a compromise design but not 4".

 

[motive]

When you can see the bump steer in the slow mo shots in the latest "Visions of Victory" video...its too much!