Is there already a cure for bumpsteer? ....with video!

[Jon]

Is there anything out there that completely removes the bump steer on a linkpin or balljoint?
Parts, tricks or methods, looking for anything really.

[Zach Gomulka]

Make sure the steering dampner is in good health, and I've heard those flip kits for the tie rod ends do some good if the car is down on adjusters

[Bruce]

..... completely removes the bump steer .....

Nothing.

This is about the best I've seen:

[Bruce]

........

[Hotrodvw]

I don't really have much of it if any......  Be sensible about how you set up your front end, use quality parts, and have it aligned properly is all I do...

[Jon]

Thanks Bruce, is this something that's available over the counter?
Looks good!

How about dune buggies builders, or race chassis builders... someone must be close to perfect?

[gizago]

Some ideas here-

http://cal-look.no/lounge/index.php/topic,11053.0.html

 

[Jon]

Thanks Gizago!

But who would I call for this?

[BeetleBug]

Thanks Gizago!

But who would I call for this?

Bump Busters?

[Jon]

Is there really a point in removing the bump steer? I know I would like to remove it, but what would I gain, if anything?

[Bruce]

Is there really a point in removing the bump steer? I know I would like to remove it, but what would I gain, if anything?

Stability and safety at 174 km/h.

[Bruce]

Thanks Bruce, is this something that's available over the counter?

There's a seller in .de that has a bolt-on kit. 

It's a VW Polo rack.

[Fasterbrit]

Bump steer is the scariest thing on the road in a fast VW. You can literally change lanes with every bump! Cure bump steer and the car becomes much more predictable and safe!

[Jon]

Thanks Matt! I wonder if it would effect braking to some degree to?

[Bruce]

Thanks Matt! I wonder if it would effect braking to some degree to?

When you hit the brakes hard, bump steer will cause the car to veer to the left a bit.  Reducing bump steer will reduce this.  Don't think your car doesn't do this.  You are just unconsiously counter steering when it happens.

[Jon]

I bet your right Bruce, but I was thinking about optimum grip between ground and tire during breaking... would the traction benefit from having wheels that wasn't "skidding" while doing a toe out, as they are bound to do with bump steer present.

[Fasterbrit]

In the link posted above there is a lot of discussion o n the JCL method of using a common link bar between both spindles and one long bar to the steering box. This is the method a lot of racers use (me included) and works supremely well. The difference is night and day, especially on cars with narrowed beams as they are more susceptible to bump steer. I have done this mod to road cars too, and can say without a doubt, that it is the best move you can do for little money to make a VW drive in a predictable straight line.

[Jon]

It might be a improvement, but whats really goes on is that you remove the toe-in/out situation... meaning that both your front wheels are now turning the same way when you hit a bump.

[Jon]

I have been surfing the net for a week now and it seems there is nowhere to buy a bump steering free steering system.
Eight years ago I figured out how to make a rack and pinion system that would eliminate bump steer when going straight, with either one or two wheels soaking up bumps.
I'm not talking about very little bump steer, I'm talking about ZERO bump steer. Even more interesting is that my system also removes all bump steer, even when you are negotiating a turn.

I have never thought much about this since that night I figured it out, but when I saw Pete Shattock's car in the latest Volksworld, it brought it to my attention again.
Just to be sure I built a live size test and it was just as good as in theory, the best thing is that it looks like its going to be bolt on, rack and pinion and it fits without cutting the floorpan or the body.

I've have been talking to a knowledgeable and reputable CNC machinist within our hobby about machining the actual parts, as it need to be 100% correct to work.

But it would be much easier to buy it, IF it exists... but it look's slim this far.

Jon Hroar Ulstad
-Hot Owl / Revestreker

[Stephan32]

With a good and proper set up of your suspension there will be no bump steer!

1) Use an original front beam and weld adjusters in ( good ones, german made )
2) Use good shocks, red Koni
3) Use camber adjusters
4) Use a good steering damper
5) Use caster shims

And do not set your car to low!!!

I have zero bump steer with all the above fitted!!!!






 

[Jon]

Please go home and check before you contribute any more to this thread. Bump steer is built in to the VW design.

And what's with all the !!!! ?

[Jon]

<a href="http://www.youtube.com/v/MvZ2ApH_l_o" target="_blank">http://www.youtube.com/v/MvZ2ApH_l_o</a>

This is full articulation of the suspension (the stopper was cut off), as you can see there is no movement of the spindle. The only thing limiting the travel is the tie rod ends binding.

I did the same with a feeler gauge later and as you can see, there is not 1 hundreds of a millimetre movement until the tie rods jerks it 3 hundreds out when it binds, to me that's ok after 350 mm of travel.
<a href="http://www.youtube.com/v/AQhOCVpCNJs" target="_blank">http://www.youtube.com/v/AQhOCVpCNJs</a>

It works during turning too, but haven't recorded it yet.

If this was a bolt on kit, with optional ratios on the rack and pinion, would you considering buying it?

Unless it's already out there?

Jon Hroar Ulstad

[Worm]

In the link posted above there is a lot of discussion o n the JCL method of using a common link bar between both spindles and one long bar to the steering box. This is the method a lot of racers use (me included) and works supremely well. The difference is night and day, especially on cars with narrowed beams as they are more susceptible to bump steer. I have done this mod to road cars too, and can say without a doubt, that it is the best move you can do for little money to make a VW drive in a predictable straight line.

You have my attention.  Post some pics how to do this.  What do you need/use to attach two tie rods to the one side?  That is if I am looking at the correct previous green lined pic.  Advice and helpful ideas for this are greatly appreciated.  The South Orange County freeways are treacherous on my well being.  The vert jumps around the bumpy lanes like a lizard.   

[Steve DKK]

Im a witness to that.

[volkskris]

I want to see pictures of this, sounds very interesting
Kristof

[Worm]

Thank you BOTH for your valuable and yes, informative help on this subject.

No pictures.  Sorry.  And Yes Steve did see it.  We were on our way to Bug In and the right front tire was riding a small groove cut in the freeway and when the groove ended sharply to the left, so went the car.  Really hard and really fast.  Plus the bugger just bounces around WAY too much.  Tired of death gripping the steering wheel over 55 mph.

[DKK - Lisa]

Thank you BOTH for your valuable and yes, informative help on this subject.

No pictures.  Sorry.  And Yes Steve did see it.  We were on our way to Bug In and the right front tire was riding a small groove cut in the freeway and when the groove ended sharply to the left, so went the car.  Really hard and really fast.  Plus the bugger just bounces around WAY too much.  Tired of death gripping the steering wheel over 55 mph.

Oh WORM... I saw it too while traveling directly behind you!  Quite frightening to witness.  Looked like an E-ticket ride without all the regulated safety features.  YIKES 

[Svwerker]

<a href="http://www.youtube.com/v/MvZ2ApH_l_o" target="_blank">http://www.youtube.com/v/MvZ2ApH_l_o</a>

This is full articulation of the suspension (the stopper was cut off), as you can see there is no movement of the spindle. The only thing limiting the travel is the tie rod ends binding.

I did the same with a feeler gauge later and as you can see, there is not 1 hundreds of a millimetre movement until the tie rods jerks it 3 hundreds out when it binds, to me that's ok after 350 mm of travel.
<a href="http://www.youtube.com/v/AQhOCVpCNJs" target="_blank">http://www.youtube.com/v/AQhOCVpCNJs</a>

It works during turning too, but haven't recorded it yet.

If this was a bolt on kit, with optional ratios on the rack and pinion, would you considering buying it?

Unless it's already out there?

Jon Hroar Ulstad

Cool! I think you can sell that towel for good money. 

[Jon]

Thanks Svwerker!

[Peter Shattock]

Hi JHU,

All very interesting stuff and I think svwerker is right, there could be a market for white towels!

I just wanted to confirm what you said about the bump steer being in one direction with the "JCL" set up. This is quite true, its not perfect. Clearly there is an element of bump steer as the long arm is moving in an arc from a fixed point, its just to the point where its not detectable through the steering wheel when set up correctly. In my case the set up is made much easier due to limited suspension travel. I've set my car currently to a point where there is very limited travel up and down (about 70mm up and around 60mm down from static). Originally I did this to prevent the need for body mods or to cut the frame head when I switched to this set up. I say "currently" above as I have traditionally used adjustment in the front suspension downward travel to control weight transfer and traction when leaving the line and as things stand I would prefer some more adjustment, which means more downward travel in the suspension which would give me frame head clearance issues, so I have a potential job to do here, but I'll wait to see how the car behaves this year with the new motor before doing anything. There is a video clip on the outlaw website http://www.offdrc.co.uk/videos its near the end of the list so scroll right, and it shows you what I mean in terms of the suspension downward travel from the static position (I also have to mention that you cant help but notice that the little street car caught Dave D knapping of the line (well worth a beer). Mind you Dave did wheelie past me to put me back in my place!).

It would be interesting to hear what experiences others (Matt K, Paul W that I know run the system) have with more suspension travel, that have run this set up. 

What Matt has said though is also true in my experience at least as the improvement over the long and short arm was massive, and I would recommend it to anyone who is experiencing problems. Its not expensive in terms of parts which are all readily available at your local machine / race shop. That said it does take time to set up for those who are wondering and its not just a bolt on job, it does need some careful adjustment, and I found that small differences in set up made a large difference in outcome.

So the up shot is if your local race shop are out of white towels, this is not a bad way forward.

Peter