Kraton Help needed - Kraton uninitiated side-to-side steering oscillation/wobble

[RC617]

So when running my Kraton 6s V5 yesterday I noticed that when letting off the throttle and off steering the front tires "steered" sided to side fairly quickly. It was like I was quickly cranking the steering wheel back and forth. When on throttle and actively giving it steering input it appeared not to be a problem. I initially though something was loose in the front chassis/steering system, however I took the tires off and checked everything and retightened everything and didn't notice any abnormal play. So this morning I gave it a go again, and it was still the same. I would run it up to high speeds and then let it coast and the side-to-side steering was very pronounced. Again if I gave it steering input it seemed to clean it up. It's almost like when no steering input is given it acts like the steering is disconnected (or the servo is self steering), however with the vehicle on and no steering input I tried to see if there was looseness or wobble in the system but it feels fairly tight and I can feel resistance from the servo. So I'm at a loss as to where the problem may be and would appreciate any thoughts.

 

[#ARRMArcfanboy4life]

Is the steering trim set to make it go straight

 

[FatCatRC]

How is the toe set on your rig? Pics? and I'm not sure with the v5's but the v4's servo saver spring is weak. If they have the same spring then add some e clips for shims or wait till the stiffer spring comes back in stock.

 

[jondilly1974]

Have you vented your tires? Its possible they might be filled with water or dirt and out of balance.

 

[Soppy]

Try adjusting the toe in or out a bit and it should stop.

 

[Primarrma]

Does this model have avc?

How fast were you thing when this occurs?
Are your retainer nuts set correctly on the hubs?

 

[RC617]

Is the steering trim set to make it go straight

As best as I can so it appears to track straight.

How is the toe set on your rig? Pics? and I'm not sure with the v5's but the v4's servo saver spring is weak. If they have the same spring then add some e clips for shims or wait till the stiffer spring comes back in stock.

I have attached some pictures (hard to tell exactly from the pictures) but nothing looks odd. Also it looks like it always have and I haven't had issues before.

Have you vented your tires? Its possible they might be filled with water or dirt and out of balance.

Yes I have, and I have witnessed what happens when not and water gets in. In that case I usually had more of a severe vibration vs side to side steering.
Currently I have the holes on the inside tapped to keep water and sand out.

Does this model have avc?

How fast were you thing when this occurs?
Are your retainer nuts set correctly on the hubs?

It does have AVC. I have a DX3 controller. To be honest I am new and not sure what this does or how it should be set. I was actually wondering if this could have some relation as we just travelled with the car/controller and it's the first time I ran it after and I'm wondering if the controller setting got moved or messed up in transport. I noticed it first at high speed, but it happens when coasting down at almost any speed.
What does AVC do and what is changed between "low" vs "high"?

 

[jondilly1974]

Turn the AVC ST RATE all the way down (CCW)

 

[RC617]

Does this model have avc?

How fast were you thing when this occurs?
Are your retainer nuts set correctly on the hubs?

Ok in my previous post I said I have AVC, but maybe I don't. I bought the Kraton used and it came with a DX3 controller that is AVC compatible, but the receiver I believe is the stock SR315 which doesn't appear to be AVC from what I can find.

 

[RC617]

Ok in my previous post I said I have AVC, but maybe I don't. I bought the Kraton used and it came with a DX3 controller that is AVC compatible, but the receiver I believe is the stock SR315 which doesn't appear to be AVC from what I can find.

Well AVC it was. I guess my "stock" used Kraton I bought came with some upgrades. It does have AVC as I checked the receiver and found it is the SR6100AT which is AVC compatible. Also, I cranked down the AVC on the controller and the problem went away. I guess it got moved when in transit. I will now need to research more on AVC, what the benefits are and how to dial it in. Thanks everyone for your help.

 

[FatCatRC]

It's your toe. One wheel is in the other is straight. You need slight toe out for offroad.

 

[ih8nixon]

From the picture you posted it looks like the SR6100AT is floating loose in the receiver box. If you're going to be using the AVC you'll need to mount the receiver inside the box using double sided foam tape for it to work properly.

 

[jondilly1974]

I have yet to find AVC/gyro useful at all. I would disable it if possible.

 

[Primarrma]

AVC is great, but people will hate it for different reasons, AVC with a decent radio can be tuned really well, on these RTR radio's it's limited.

You want to set AVC so that it doesn't cause wobbles at high speed, if you do that it shouldn't be an issue at low speed.

If you set it low and slowly increase it on each pass you should find I happy medium.

Some people will say it causes your car to fight you on jumps, and on really high speed speed run cars it isn't very good because it can't keep up, but I think it is fantastic in a lot of situations. It is amazing on loose dirt, give it a try, turn it right down/off then try and take off as fast as you can and try to keep the car straight. Now turn it up and try again, you will be amazed at the difference. It is great for heading hold the car drives really straight with no steering inputs from you.

Just be aware that avc requires you to calibrate the receiver(part of the binding process) if you make any steering ends point adjustments. Every time you turn the car on it does a level/gyro check so make sure when you turn the car on you leave it still on flat ground.

Also make sure your receiver is double sided taped down in the receiver box, if not it will cause incorrect steering inputs when driving.

If you want to see what it does, turn the car on(radio on first of cause) and then pick up the car, move the front of the car side to side and the wheels will counter steer the angle, if you can't see that then turn the AVC up for the demonstration.

I have yet to find AVC/gyro useful at all. I would disable it if possible.

I was waiting for a speed run guy to say this, I just didn't type fast enough.

 

[RC617]

It's your toe. One wheel is in the other is straight. You need slight toe out for offroad.

View attachment 135616

Thanks for pointing that out, I have adjusted it as you said

From the picture you posted it looks like the SR6100AT is floating loose in the receiver box. If you're going to be using the AVC you'll need to mount the receiver inside the box using double sided foam tape for it to work properly.

Thanks for pointing that out. When I opened it and found it floating I thought in general that would be a bad idea as it seems like it would get banged around, but now knowing AVC is tie to it, seems even more important.

AVC is great, but people will hate it for different reasons, AVC with a decent radio can be tuned really well, on these RTR radio's it's limited.

You want to set AVC so that it doesn't cause wobbles at high speed, if you do that it shouldn't be an issue at low speed.

If you set it low and slowly increase it on each pass you should find I happy medium.

Some people will say it causes your car to fight you on jumps, and on really high speed speed run cars it isn't very good because it can't keep up, but I think it is fantastic in a lot of situations. It is amazing on loose dirt, give it a try, turn it right down/off then try and take off as fast as you can and try to keep the car straight. Now turn it up and try again, you will be amazed at the difference. It is great for heading hold the car drives really straight with no steering inputs from you.

Just be aware that avc requires you to calibrate the receiver(part of the binding process) if you make any steering ends point adjustments. Every time you turn the car on it does a level/gyro check so make sure when you turn the car on you leave it still on flat ground.

Also make sure your receiver is double sided taped down in the receiver box, if not it will cause incorrect steering inputs when driving.

If you want to see what it does, turn the car on(radio on first of cause) and then pick up the car, move the front of the car side to side and the wheels will counter steer the angle, if you can't see that then turn the AVC up for the demonstration.

I was waiting for a speed run guy to say this, I just didn't type fast enough.

Great info, very helpful to know what it does and how it's useful and how to dial it in. Seems like it's similar to passenger vehicles VSA (Vehicle Stability Asist) and traction control. Definitely going to try to dial it in. You said with a decent radio it can be tuned really well....where does a DX3 radio fall? It seems like it only has a ST Rate adjustment and not some of the other adjustment something like a DX5 would have.

 

[Primarrma]

Thanks for pointing that out, I have adjusted it as you said

Thanks for pointing that out. When I opened it and found it floating I thought in general that would be a bad idea as it seems like it would get banged around, but now knowing AVC is tie to it, seems even more important.

Great info, very helpful to know what it does and how it's useful and how to dial it in. Seems like it's similar to passenger vehicles VSA (Vehicle Stability Asist) and traction control. Definitely going to try to dial it in. You said with a decent radio it can be tuned really well....where does a DX3 radio fall? It seems like it only has a ST Rate adjustment and not some of the other adjustment something like a DX5 would have.

Yes your right I think of it like traction and stability control also.

The "computer" type radio's are where you get to really configure the AVC properly. It is quite detailed, it is great to have the ability, but if it is doing what you need it is essential. The DX3 is a really great RTR single vehicle radio, one of the better one's spektrum has made.

Though the DX5c or Rugged might be a good next step up, they have multi vehicle memory and you'll be able to get some telemetry info from the smart Spektrum products, like the escs that come with most of the larger Arrma cars now.

AVC is good, but I wouldn't buy a new radio just to explore it, if you want a new radio for other reasons then the bonus is the extra control you'll have.

 

[RC617]

Though the DX5c or Rugged might be a good next step up, they have multi vehicle memory and you'll be able to get some telemetry info from the smart Spektrum products, like the escs

I actually ended up getting the Spektrum bluetooth module (BT2000) to get some telemetry via my phone app, however I had issues and it interfered with the Kratons performance so Arrma/HH wants me to send the Kraton and controller to them to investigate.

 

[jondilly1974]

AVC is great, but people will hate it for different reasons, AVC with a decent radio can be tuned really well, on these RTR radio's it's limited.

You want to set AVC so that it doesn't cause wobbles at high speed, if you do that it shouldn't be an issue at low speed.

If you set it low and slowly increase it on each pass you should find I happy medium.

Some people will say it causes your car to fight you on jumps, and on really high speed speed run cars it isn't very good because it can't keep up, but I think it is fantastic in a lot of situations. It is amazing on loose dirt, give it a try, turn it right down/off then try and take off as fast as you can and try to keep the car straight. Now turn it up and try again, you will be amazed at the difference. It is great for heading hold the car drives really straight with no steering inputs from you.

Just be aware that avc requires you to calibrate the receiver(part of the binding process) if you make any steering ends point adjustments. Every time you turn the car on it does a level/gyro check so make sure when you turn the car on you leave it still on flat ground.

Also make sure your receiver is double sided taped down in the receiver box, if not it will cause incorrect steering inputs when driving.

If you want to see what it does, turn the car on(radio on first of cause) and then pick up the car, move the front of the car side to side and the wheels will counter steer the angle, if you can't see that then turn the AVC up for the demonstration.

I was waiting for a speed run guy to say this, I just didn't type fast enough.

I have tried three different gyro systems and all of them ended up with the same effect that sent the OP here. I call it a tank knocker effect. When you turn the gyro up to the point when it will counter steer in the air, as desired, then at high speeds it will wag back and forth. If you turn it down to the point that it no longer has the tank knocker effect, it is essentially off. For me I just don’t see the point.

 

[Primarrma]

I have tried three different gyro systems and all of them ended up with the same effect that sent the OP here. I call it a tank knocker effect. When you turn the gyro up to the point when it will counter steer in the air, as desired, then at high speeds it will wag back and forth. If you turn it down to the point that it no longer has the tank knocker effect, it is essentially off. For me I just don’t see the point.

I get what you're saying, and the speeds you drive at negate the system, I was not having a go or being rude, I just know what the speed run guys say. I find it to work really well for what I do on very loose dirt, without it I can barely keep my Kraton 8s in a straight line. It helps me to line up the jumps at 80km/h too.

Yeah the tank slapper effect is bad, I know it becomes a real issue when the gain is too high. It's good we are all different in what we like otherwise our hobby could be pretty boring.

I actually ended up getting the Spektrum bluetooth module (BT2000) to get some telemetry via my phone app, however I had issues and it interfered with the Kratons performance so Arrma/HH wants me to send the Kraton and controller to them to investigate.

That's weird, what radio are you using?

 

[RC617]

That's weird, what radio are you using

I have a DX3 radio w/ SR6100AT receiver. The tech guy said they had one other claim similar to mine and they wanted a vehicle with the issue to do more testing.