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Hi! 

I am trying to create a Trophy Truck, but the steering system is giving me trouble. Whenever I turn, the wheels get stuck and the whole car slows down. I am using the pre-2011 style hubs and suspension. Anyone have any tips?

-TechnicRCRacer

image removed due to limitations

Edited by TechnicRCRacer

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The gear rack is too far forward. It turns the hubs, giving it toe-in, which is when the wheels are like this: \----/ It can be simply fixed by removing the red 1/2 beam behind the gear rack.

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The problem is, the "grey bushes" are actually attached to cross blocks with two pin holes and an offset axle hole. I forgot the part number. Without the half beam, the links hit the frame.

 

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Offroadcreat1ons is correct, the rack is too far forward. What part of the frame is in the way? Can you provide a few more pics, like overhead, side, and underside? It will be easier to help you with clearer views of the chassis. But you wanted, you can use Madoca's buggy suspension. Just mount it horizontally, and change the shocks. I hope this helps.

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With the slack in Lego parts, I don't think it's the toe in that is causing problems. I think you might be having a wheel hitting part of the chassis. Put the wheels back on, then steer to one extreme with the remote. Take the tire and try spinning it, and see if it hits the chassis anywhere. That should be it. 

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Thanks for all the help! But I know that it is not toeing in or out, and the wheels are not hitting the chassis. I can take more pictures later. I did notice that when I turn to the left, the wheel on the right turns farther than the left wheel, and the opposite happens when I turn right. When I move the gear rack back, the wheels toe out.

Also, small question: How do you get the footnotes under your post?

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1 hour ago, TechnicRCRacer said:

Thanks for all the help! But I know that it is not toeing in or out, and the wheels are not hitting the chassis. I can take more pictures later. I did notice that when I turn to the left, the wheel on the right turns farther than the left wheel, and the opposite happens when I turn right. When I move the gear rack back, the wheels toe out.

Also, small question: How do you get the footnotes under your post?

It sounds like you have a type of ackermann steering setup.

To get the footnotes under our posts, go to your account, settings, then signature. write whatever you want to be in your signature there, then press save.

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It looks as if you unintentionally borked your Ackerman setup. I have implemented a setup like this that uses angled links to get the correction. What you want with Ackerman correction is to have the inside wheel turn more than the outside wheel. Your setup means the outside wheel turns more than the inside one, which is not good. I'd reccomend you flipping your axle so that the steering links are behind the axle rather than in front.

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Is your servo properly centered? From the ONLY picture, it appeared that at rest, your pinion is not resting at the middle of your gear rack.

And if the outer wheel turns more than the inner wheel, either you really have toe in (just not visibly noticeable), or you've steered too much (happens when your steering link, wheel pivot and steering pivot forms (too close to) a straight line) - try to limit your steering angle.

Edited by PorkyMonster

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Fixed!

Finished a new steering system with you guys' advice and it works like a charm! Thanks!

Here would be a picture of the half-finished Trophy Truck (uses Sbrick +)

The image was having problems uploading

 

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