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Old 02-13-2017, 07:15 PM   #1
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Default steering setup help

what / how do the pros set up steering? what order?

endpoints left and right

then turn down dual rates 10% 20%

skip expo?

any tips?
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Old 02-15-2017, 02:47 AM   #2
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EPA, no expo as what you gain in ease of driving around the center you lose along the way and the car suddenly does things, then it's all in the fingers I'd rather encourage you to learn to turn the steering wheel less while still having some margin, rather than dial in some dual rate, but to each his own on this one
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Old 02-15-2017, 08:57 AM   #3
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The first step in setting up steering is to make sure that all steering components are installed properly in the car and can move freely. Make sure all linkages/horns are the correct lengths and installed at the correct angles when the steering is at neutral. At a minimum, I would at least confirm that both steering turnbuckles are the exact same length since most cars use symmetrical steering setups.

If you spend a bit of extra time making sure the steering is installed properly in the car, it will make it easier to adjust everything with the radio. If you do your work properly, the endpoint adjustments in the radio should be exactly the same.

The first adjustment I always do on the radio (if it has it) is to use SUBTRIM to make sure the steering mechanism is at dead center. You should never just use trim to center your radio, as it will affect how much throw the servo has left vs. right. For example if you only use trim to move the servo right to center the steering, the car will now have more mechanical steering right than it will have left. Since some inexpensive radios don't have subtrim, you might not have any choice but to use it. However if you find you are having to use a lot of trim to center the servo/steering, chances are there is something mechanical wrong. You may also need to check the the servo horn is installed correctly.

Next you will want to adjust the throw/endpoints to the maximum recommended of the kit you are running. Usually the maximum will be where the steering knuckle just touches the caster blocks. If you allow the servo to move more than the steering mechanism will allow, it can damage the servo.

The next adjustment is to adjust the dual rate if the radio has it. Rarely do we use all of the available mechanical steering when we are racing. If you set the dual rate to the amount of steering you need to make a complete circle around the tightest part of the course, that is usually a good starting point. You can then add/remove steering depending on the handling of your car.
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Old 02-15-2017, 11:04 AM   #4
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At the bottom of this post is a quick chart I made in relation to setting steering on an R/C car.

Here is a brief explanation...

Most cars have a mechanical limit to their steering knuckles when they aren't attached to the steering rack that can be over 90+ degrees of movment (45+ degrees left/right). However at very extreme steering angles we can get binding in the moving components. Usually the steering rack/components limit how far the steering can go. But even with everything connected, the mechanical steering limits of a particular car may still cause issues, such as the steering knuckles hitting the caster blocks, binding in cvds, or dog bones popping out of their input cups. Therefore we can use our radios to limit how far the servo will allow the steering mechanism to move. In the radio this is usually called travel or endpoint adjustment.

On some basic radios, there is only endpoint adjustment. Since you usually don't want 100% of the available mechanical steering when grip racing, you would turn down the travel/endpoint so that you can easily make a u-turn at the tightest portion of the track. Depending on the track layout/conditions this still may be more steering than needed, so you might even turn down the endpoint more. The primary reason for turning down the steering is that it will make a car easier to drive down a fast straight and also not scrub as much speed through a tight corner.

On more advanced radios, there is usually an additional adjustment either called steering or travel % (percentage) or dual rate. This adjustment allows you to reduce the total percentage of steering based on whatever the current radio travel or endpoints are set to. Basically you can set the radio so you have maximum usable travel and then turn down the % of travel to suit the track layout/conditions. This adjustment is often programed to a toggle switch or scroll wheel on the radio which allows the driver to adjust steering without going into the radio setup menu.

So to summarize...
- All cars have a mechanical steering limit which may be more than needed/wanted
- You then use travel or endpoint adjustments in the radio to limit how far the servo can mechanically move the steering
- You can then use steering%/travel %/dual rate to further limit steering based on the whatever the current endpoints are set at.

One more thing to note about dual rate. Dual rate can allow you to adjust the left or right steering independent of each other. This can come in handy when racing on an oval track. On an anti-clockwise oval track, you would want more left steering and very little right steering. Usually most radios that offer dual rate will also allow you to program a button to give you 100% of the steering as needed(based on the radio endpoint adjustments). This can come in handy if you are racing and get stuck in a tight situation and need to do a quick u-turn.


Attached Thumbnails
steering setup help-steering.jpg  
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Last edited by IndyRC_Racer; 02-15-2017 at 12:13 PM.
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Old 02-15-2017, 12:30 PM   #5
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As far as steering exponential (often abbreviated as steering expo)...

Steering exponential rates do not normally affect how far the steering can travel (based on the current radio endpoint adjustments). What is does do is affect how much the steering actually travels in relation to the movement of the radio's steering wheel.

You can adjust the exponential so that if you move the radio wheel a lot that the steering servo will move less initially. You can also go the other way so that if you move the radio wheel a little that the steering will move more initially. Many drivers like to use a little expo to help settle down their car when driving on fast straights. Since we aren't sitting in the car, it is easy to over correct and use more steering input than needed. However other drivers see this setting as crutch, and recommend learning to use a light touch on the wheel.

Steering exponential can be nice if you are new to racing or if you suffer from shaky hands when racing. If you do use this feature, I would recommend going with less than more. I would at least encourage people to play around with this setting in the pits if their radio has it so they can better understand how it actually affects steering.

One last thing about steering exponential. At either end of the exponential extreme, it can either make the car have virtually no steering or instantaneous full steering.
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Last edited by IndyRC_Racer; 02-15-2017 at 12:41 PM.
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