Stabilizer / Sway Bar question

[Collin 2047]

Hi guys.

I am searching and searching but cant find a satisfying answer. So please let me explain. Basicly I understand what it is made for and how it works. My specific question is ONLY about offroad buggies. in my case a 2WD rear driven Dyna Storm.

Now I can remember some guys from the track with lot of experience ( at least I guess : ) told me, sway bars on 2WD does not make sense at the rear, only at the front suspension.
Right now I am tinkering around to fit them, also thinking about installing them at the rear.

So guys, can you tell me about this front/rear thing with sway bars? I only remember I had a Losi XXX once, the additional stabi set contained front and rear. I think Gil Losi was not so stupid to offer some stabilizers which does not make sense. Also I think the old guys from the track does know what they talk about...

Please let me know whats your experience about.

[Superluminal 3896]

They seem to be fitted to the rear of quite a lot of vintage Ultima's so I assume they achieve something useful. I would have thought they would be equally as useful whether 2wd or 4wd as they will reduce the chassis roll in cornering which may be of benefit on both irrespective of which are the driven wheels. And they look very cool.

[Alangt4 123]

Basic effect of the rear arb- either adding it or making existing one stiffer will tend to make a car that had neutral handling more prone to oversteer. Can make the car more twitchy as a result and less consistent to drive close to its limit. Can make it more reactive to bumps and suspension less supple, with wheels not tracking the ground as well.

for 4WD or fwd they can work well to counter the under steer they can have as long as you don’t have too high a rate that again starts to interfere with normal suspension action.

[Willy iine 18829]

59 minutes ago, Collin said:

Hi guys.

I am searching and searching but cant find a satisfying answer. So please let me explain. Basicly I understand what it is made for and how it works. My specific question is ONLY about offroad buggies. in my case a 2WD rear driven Dyna Storm.

Now I can remember some guys from the track with lot of experience ( at least I guess : ) told me, sway bars on 2WD does not make sense at the rear, only at the front suspension.
Right now I am tinkering around to fit them, also thinking about installing them at the rear.

So guys, can you tell me about this front/rear thing with sway bars? I only remember I had a Losi XXX once, the additional stabi set contained front and rear. I think Gil Losi was not so stupid to offer some stabilizers which does not make sense. Also I think the old guys from the track does know what they talk about...

Please let me know whats your experience about.

In a nutshell if things were equal and consistent, it is somewhat a fact that most RWD cars do not run stiff setting on the rear to prevent oversteer.

But every car is different and some are just horribly weight distributed and sometimes a rear sway bar can help horrendous understeer unless softening the front suspension setting in totality.

So you're approaching it right by 'tinkering around' to try to find that sweet neutral spot for your driving style.  For me, the first thing I change is not adding/subtracting a sway bar from factory setting, but adjusting the front/rear weight distribution by changing height adjustment, damper spring stiffness give it more or less rake, etc and if the car is beyond the damper spring/height parameters, then consider adjusting the sway bar setting.   (or play with weights).

 

 

[Saito2 7654]

I don't like to make blanket statements like this or that will never work or always work. I consider sway bars, whether installed or not, to be a tuning aid that may or may not be helpful depending on the platform and the terrain its run on.

[Collin 2047]

Seems so. But better having a nice possibilitiy to mount them both.

Guys, again thanks for your thoughts.

[BuggyGuy 1140]

Ok - so let's asume your going round a right hand bend with no rear stabilizer bar: the outside wheel will compress the suspension on the left hand side, and the chassis will "roll" to the left around it centre line, the inside wheel will drop only as far as droop settings allow and most likely leave the track surface. The amount the inside wheel needs to drop in order for that wheel to remain in contact with the track has increased over the norm as the chassis is lower to the ground on the outside of the turn and higher from the ground on the indside of the turn (AKA chassis roll.)

With an anti roll bar the amount of chassis roll is reduced, this increases the chance of the inside wheel remaining in contact with the ground as the chassis will remain more parallel to the tracks surface. This makes it more likely the inside wheel will be able to remain in contact with the ground.

Needless to say - the more contact you get get between the car and the ground the better, so less chassis roll = more contact with the track = more stability and control.

Edit: This also explains why you need thicker sway bar on higher grip surfaces but can get away with thin or no bars on low grip surfaces.

Edited February 20, 2022 by BuggyGuy

[slydar 242]

19 hours ago, Collin said:

Hi guys.

I am searching and searching but cant find a satisfying answer. So please let me explain. Basicly I understand what it is made for and how it works. My specific question is ONLY about offroad buggies. in my case a 2WD rear driven Dyna Storm.

Now I can remember some guys from the track with lot of experience ( at least I guess : ) told me, sway bars on 2WD does not make sense at the rear, only at the front suspension.
Right now I am tinkering around to fit them, also thinking about installing them at the rear.

So guys, can you tell me about this front/rear thing with sway bars? I only remember I had a Losi XXX once, the additional stabi set contained front and rear. I think Gil Losi was not so stupid to offer some stabilizers which does not make sense. Also I think the old guys from the track does know what they talk about...

Please let me know whats your experience about.

I have three   1/10th race buggies. I'm not a veteran, but I've made the A main every race so far this year.

I'd say the rear is more important than the front as a general statement, and you will definitely find more full scale vehicles with rear only. Obviously the dynamics of a rear engine RWD 10th scale off-road buggy are different, but not completely. 

A few points. With off-road RC cars, you have jumps and turns. So choosing the spring rates and ground clearance is always a compromise. ARB's can help with this compromise (sometimes) but it does add complexity. I would always think if you are starting from scratch, and the kit does not come with ARB's, or even if it does, leave the tuning of the ARB's till last, as a fine tuning method. With the Dyna though, they may certainly help because you have such limited adjustments with roll center, anti dive, castor, etc.

My Xray XB2C had none when I got it. I recently softened the spring rate as our track is a little less grippy than it was. I added a a rear bar, (1.1mm, then 1.2, now back to 1.1) and this really helped. If you read up about full scale suspension dynamics, its often said the rear ARB affects the front more, and vice versa. I definitely found this to be the case. Also the XB2's didn't really have provision for a front ARB until the 2020 models were released. 

My Durango DEX410 has them fitted front and rear. I removed the front to get a little more grip and because this seemed to be a very common setup on the set up sheet's for this model, seemed to help a fair bit.

My Serpent SDX4 Has them fitted front and rear and I have not touched them. The car handles amazingly well. Comparatively I do my fastest laps with this car.

I'm currently tuning my Top Force to work a bit better on the track. I've recently gone to MUCH softer spring rates, as the car is super light compared to the modern buggies. Soft springs helped a lot, and I am going to play with this more first, but I have the feeling adding them to this car, even though tricky as they were never offered for DF01 (to my knowledge) will make a very positive difference. Lots of people setting these up to race on modern tracks seem to go to the trouble to add them on their builds. 

Hope you can make sense of this, and it helps.

 

[Alangt4 123]

Hey-  the Ta01 touring car stabiliser works on the DF01- I have one on one of my top force cars. Hard to pick up these days though. You can copy the mounting used and get a few other stabilisers in there… can’t recall which ones sorry.

[Collin 2047]

On 2/21/2022 at 1:32 PM, slydar said:

I have three   1/10th race buggies. I'm not a veteran, but I've made the A main every race so far this year.

I'd say the rear is more important than the front as a general statement, and you will definitely find more full scale vehicles with rear only. Obviously the dynamics of a rear engine RWD 10th scale off-road buggy are different, but not completely. 

A few points. With off-road RC cars, you have jumps and turns. So choosing the spring rates and ground clearance is always a compromise. ARB's can help with this compromise (sometimes) but it does add complexity. I would always think if you are starting from scratch, and the kit does not come with ARB's, or even if it does, leave the tuning of the ARB's till last, as a fine tuning method. With the Dyna though, they may certainly help because you have such limited adjustments with roll center, anti dive, castor, etc.

My Xray XB2C had none when I got it. I recently softened the spring rate as our track is a little less grippy than it was. I added a a rear bar, (1.1mm, then 1.2, now back to 1.1) and this really helped. If you read up about full scale suspension dynamics, its often said the rear ARB affects the front more, and vice versa. I definitely found this to be the case. Also the XB2's didn't really have provision for a front ARB until the 2020 models were released. 

My Durango DEX410 has them fitted front and rear. I removed the front to get a little more grip and because this seemed to be a very common setup on the set up sheet's for this model, seemed to help a fair bit.

My Serpent SDX4 Has them fitted front and rear and I have not touched them. The car handles amazingly well. Comparatively I do my fastest laps with this car.

I'm currently tuning my Top Force to work a bit better on the track. I've recently gone to MUCH softer spring rates, as the car is super light compared to the modern buggies. Soft springs helped a lot, and I am going to play with this more first, but I have the feeling adding them to this car, even though tricky as they were never offered for DF01 (to my knowledge) will make a very positive difference. Lots of people setting these up to race on modern tracks seem to go to the trouble to add them on their builds. 

Hope you can make sense of this, and it helps.

 

Hi. Yes it helped a LOT : ) I am tinkering around the front ones now and made some progress. Its really narrow there and the may I do it will be very sophisticated at the end. (at least I hope so : )

Now a very basic question, the wire, which is basicly a spring, sould only gain a springload when arms are moving up and down, right?
I spotted on my built, that the wire works on some certain points as a spring but between ball-connectors and bearings/clip (wherer the wire is mounted).

In other words, the wire should only be bent from the weight of the suspension arms and the repressure of the shocks. In all other directions it have to move free with no blocking/locking.

Hope I explained it well enough to understand? Thanks in advance.

 

 

 

[Willy iine 18829]

Sway bars are basically just torsion bars so yes, they only work when one suspension arm is working against the opposing side.  

If on flat ground the sway bar basically has no function (in simple terms) as the bar is relaxed.   This is why it is sometimes funny watching folks trying to remove shocks/struts on 1:1 cars while only one side of the car is off the ground.  Damage bolt threads often?  

[Collin 2047]

Just now, Willy iine said:

Sway bars are basically just torsion bars so yes, they only work when one suspension arm is working against the opposing side.  

If on flat ground the sway bar basically has no function (in simple terms) as the bar is relaxed.   This is why it is sometimes funny watching folks trying to remove suspension on 1:1 cars while only one side of the car is off the ground.  Damage bolt threads often?  

Nahh... I know : )

Its more the behaviore of the wire between mount to the suspension arm and the point where it rotates (is bolt to the chassis center). Hard for non native english to explain.

[Willy iine 18829]

2 minutes ago, Collin said:

Nahh... I know : )

Its more the behaviore of the wire between mount to the suspension arm and the point where it rotates (is bolt to the chassis center). Hard for non native english to explain.

Sorry, I think I'm just not reading your post correctly..!  

[slydar 242]

On 3/6/2022 at 8:51 AM, Collin said:

Hi. Yes it helped a LOT : ) I am tinkering around the front ones now and made some progress. Its really narrow there and the may I do it will be very sophisticated at the end. (at least I hope so : )

Now a very basic question, the wire, which is basicly a spring, sould only gain a springload when arms are moving up and down, right?
I spotted on my built, that the wire works on some certain points as a spring but between ball-connectors and bearings/clip (wherer the wire is mounted).

In other words, the wire should only be bent from the weight of the suspension arms and the repressure of the shocks. In all other directions it have to move free with no blocking/locking.

Hope I explained it well enough to understand? Thanks in advance.

 

 

 

remove the shocks/damper from the car. Also the wheels. If the ARB is working correctly, if you lift one arm, the other should lift too. When I service my car I'll make a video. 

[alvinlwh 7227]

Someone on this forum once sent me this video to help me set up my roll bars. 

 

[slydar 242]

On 3/6/2022 at 9:00 AM, Collin said:

Nahh... I know : )

Its more the behaviore of the wire between mount to the suspension arm and the point where it rotates (is bolt to the chassis center). Hard for non native english to explain.

this seems a bit redundant now with the other video just posted, but anyway