Kraton Kraton 6s exb only steers to one side

[Luggas_H1]

My Kraton has been running fine with a plastic servo horn for a few runs now, until i stripped it (it was only a matter of time i knew that woudnt last). After that I bought an Aluminium Servo horn from the V4 RTR Kraton, and now it only steers to the right when the wheels are on the ground. When the wheels are off or not touching the ground, it steers normally and everything seems to be put together properly. What i also noticed is that the servo moves around quite a bit in the mount. I've tried diffrent horns and servos so i think there has to be something wrong with the car's steering linkage but i have no idea what that could be. Also ive noticed that my fans come on when i turn the wheels by hand, so maybe its something electrical? Has anyone got the same problem here or any tips what i should try next?

 

[Jgg12002]

How about a video showing problem. Servo moving around seems funny.

 

[L3phturn]

Need a lot more information. It could be lots of things. Servo loose in the mount, bad servo, linkage binding, end point settings, calibration, servo saver... lots more. Video would be good. With the top off of it steer left. What moves and what doesn't? You'll be able to narrow down the options pretty quickly.

 

[Luggas_H1]

ok so ive just uploaded this to youtube. i know this isnt the best but this is all i had before i ripped it apart where it currently stands.

 

[Kla912000]

Seems normal to me. There's always a bit of resistance when the rig is on the ground. You can always try tightening the servo saver a bit. How does it turn when you drive it?

 

[L3phturn]

ok so ive just uploaded this to youtube. i know this isnt the best but this is all i had before i ripped it apart where it currently stands.

Looks like either the suspension is binding somewhere or that servo is failing/too weak. Step 1 is to disconnect the servo and try to move the steering by hand both in the air and with wheels on the ground. Does it move smoothly/freely or is something binding? Do you have another servo to test? What servo do you have in it exactly?

 

[Luggas_H1]

It does not turn well when i drive it, its become super unresponsive and inconsistent compared to how it was before so the resistance is not normal and it already caused me to wreck because corrections are not possible when it turns quickly to the right and slowly to the left. there is no binding ive already disconnected the servo and moved everything by hand and it turns fine. the first servo i tried was an 18kg one from a hoabo hyper(the one in the video), i thought it had burnt out or got damaged during the crash that broke the plastic horn BUT i borrowed a 20kg servo from a friend which i know works and it does the same thing. weirdest thing is i haven't found anyone with an isse similar to mine on the entire internet.

 

[SrC]

My Kraton has been running fine with a plastic servo horn for a few runs now, until i stripped it (it was only a matter of time i knew that woudnt last). After that I bought an Aluminium Servo horn from the V4 RTR Kraton, and now it only steers to the right when the wheels are on the ground. When the wheels are off or not touching the ground, it steers normally and everything seems to be put together properly. What i also noticed is that the servo moves around quite a bit in the mount. I've tried diffrent horns and servos so i think there has to be something wrong with the car's steering linkage but i have no idea what that could be. Also ive noticed that my fans come on when i turn the wheels by hand, so maybe its something electrical? Has anyone got the same problem here or any tips what i should try next?

What servo is that you are talking about? A stocker Spektrum one ? Came With the 23 spline Spektrum servo arm?
The V4 RTR Kraton servo horn is 25 Spline.
You might be using the wrong type of Servo horn there. And also maybe that plastic horn you used was wrong, IDK.
Need more info.
What exact servo are you running? Is it a 23 spline stocker one or a 25 spline upgrade Servo.
Spline meaning number of teeth serrations on the servo's output shaft which attaches to the Arm. The arm should have same matching number of splines. 23 or 25 splines.
Get back...




EDITED:
If the above checks out>>>

>>>Just looked over the video better in slow motion.
Your Servo Saver Spring is too weak IMHO.
Swap it out with the "X-Hard" option SS spring or Shim the existing SS spring. Shimming is easier. There are threads here in regards.
Also, double check your Steering Endpoint adjustments. Hard to say, but it looked too extreme in the video. Reduce travel slightly. Both L and R sides.

 

[Jgg12002]

Is there play in the circled part of the joint? Seems like it at the end of the video.

 

[Luggas_H1]

@ steve My exb came with the 23t spline that i've never used. both of the servos were 25t which is why i had a plastic one in the beginning (25t) and later upgraded to a 25t aluminium one. servo saver cant be too weak because then the arms would move but the wheels woudnt turn because the torque would slip through at the saver, which is not whats happening as the servo just kinda gives up when i turn left. it cant also be the end points because when the wheels are off, it turns normally.
@jgg holy that is some detective work right there, i do see the play in the video and i just checked, the nut and screw were a bit loose, (about one full turn from fully tight) but arent they supposed to be? anyway ive slammed them together as hard as i can and it still moves freely so ill put everything together tomorrow and let you know if that helped.

 

[SrC]

Ok you have the correct 25 spline Arm for the 25 spline servo.
Your Servo Saver spring is too weak when under load. Been there, same scenario as yours.
The tension of the SS spring is overcome by the weight of the chassis and friction of the wheel's. SS can slip more so in one direct than the other. Like in your case, only getting travel at one side.
If you look closely at the servo saver while steering placed on the floor with a flashlight, you will see the servo saver is slipping in one direction. It won't slip off the ground. It won't even necessarily slip both ways as in your case.
Just take a look first at your servo saver like I said with a flashlight. If the servo saver stays locked, then perhaps the Servo is toast. Worst case. And I've had servos fail to turn one direction when under load.
It will be very obvious if you look close at the SS while steering it on the ground. This will visually show you if it is the SS or not being the issue. Usually it is.

 

[parcou]

@ steve My exb came with the 23t spline that i've never used. both of the servos were 25t which is why i had a plastic one in the beginning (25t) and later upgraded to a 25t aluminium one. servo saver cant be too weak because then the arms would move but the wheels woudnt turn because the torque would slip through at the saver, which is not whats happening as the servo just kinda gives up when i turn left. it cant also be the end points because when the wheels are off, it turns normally.
@jgg holy that is some detective work right there, i do see the play in the video and i just checked, the nut and screw were a bit loose, (about one full turn from fully tight) but arent they supposed to be? anyway ive slammed them together as hard as i can and it still moves freely so ill put everything together tomorrow and let you know if that helped.

Although I could turn in both directions it was half of what you can do turning it right when on the ground. I had to do the hack to shim my Kraton EXB servo saver and this was still with a better servo. If no binding in your suspension and that plastic servo horn is not giving way, my money is on the servo saver to be shimmed and better servo 35kg servo.

HR servo horn is a good metal upgrade. https://www.amazon.com/gp/product/B072YJ6L4C/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

[Luggas_H1]

i made 2 more videos and you can see the saver is NOT slipping when the wheels are on the ground and i also filmed how much the servo mount moves around and there is also a clunk sound when turning to the right (the direction that works) which is weird.

 

[slick2500]

Remove the servo arm from the steering linkage does your steering move freely? In the top video I can hear something binding in your steering. Also check to make sure that the screws are threaded completely into the servo mount it doesn't look like any of the screws are tightened down at all. There should not be any movement there.

 

[parcou]

i made 2 more videos and you can see the saver is NOT slipping when the wheels are on the ground and i also filmed how much the servo mount moves around and there is also a clunk sound when turning to the right (the direction that works) which is weird.

Also your servo body is doing more movement or the mount that I would accept from mine. Could be just me.

 

[Luggas_H1]

Ladies and Gentleman. We got em. this lil red bar in the steering linkage is bend. As you can see, there are marks on the diffcase. I got the idea to check it out when i saw someone complain about this bar having 0 clearance out of the factory and sure enough, a tiny bend, which probably happend in the same oopsie that stripped my plastic servo horn, added extra resistance when turning to the left due to it rubbing on the diffcase. No im NOT gonna bend it back, im gonna order a new one. Then we should be good.

 

[L3phturn]

Ladies and Gentleman. We got em. this lil red bar in the steering linkage is bend. As you can see, there are marks on the diffcase. I got the idea to check it out when i saw someone complain about this bar having 0 clearance out of the factory and sure enough, a tiny bend, which probably happend in the same oopsie that stripped my plastic servo horn, added extra resistance when turning to the left due to it rubbing on the diffcase. No im NOT gonna bend it back, im gonna order a new one. Then we should be good.

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That thing needs a serious cleaning. That sand will tear stuff up.

I suggest the CF set that includes the ackerman bar (the bit you bent) from BasherQueen. Light and strong - it will never bend.
https://www.ebay.ca/itm/154406327051?hash=item23f355930b:g:a7MAAOSw1hRgboec

I just noticed her servo saver set - I'm going to order a couple of these right now!
https://www.ebay.ca/itm/154870025902?hash=item240ef90eae:g:XlsAAOSw0pthwOPO