Typhon Typhon 6s front tire Ballooning

[Kevinbosch711]

New bee here I have a new 6s running 6 lipo the front tires are ballooning pretty bad how can I fix this? Change the Differential?

 

[avogev]

i ended up changing the fluid. 500k and it stabalizes everything really well. acceleration is better and front tires aren balooning.

 

[Primarrma]

Center diff fluid 200k should be enough. Just remember when you thicken diff fluids(front and rear) it reduces your turning action. A thicker center diff fluid will give you good forward drive, but will be less forgiving.

 

[avogev]

Center diff fluid 200k should be enough. Just remember when you thicken diff fluids(front and rear) it reduces your turning action. A thicker center diff fluid will give you good forward drive, but will be less forgiving.

huh? id need more explanation on this...front and rear diffs getting thicker fluid effects turning yes. but center diff?

 

[Kevinbosch711]

i ended up changing the fluid. 500k and it stabalizes everything really well. acceleration is better and front tires aren balooning.

You did all three or just the front ?

 

[bicketybam]

Get belted tires. Problem solved.

 

[Primarrma]

huh? id need more explanation on this...front and rear diffs getting thicker fluid effects turning yes. but center diff?

The center diff will mostly effect the drive, if you have a light center diff it tends to be forgiving over bumps, if it's thick you'll get good drive, but when it gets rough it will dart all over the place. Not an issue usually for bashing, plus the thicker fluids are a benefit in the air.
Lighter diffs are better if you aren't able to control your finger, they bleed the power if you snap the throttle on.

 

[Yonic]

huh? id need more explanation on this...front and rear diffs getting thicker fluid effects turning yes. but center diff?

It does effects turning - under power. when under power the weight transfer backwards so the fronts have less traction, on more open diff the power will bleed to the front, so the rear will push less, and instead the front will “pull” the car into the corner, but with a thick center diff the power don't bleed to the front, and so you just under-steer.

One thing you should consider with going to a thick diff, is that this will double the load on the front/rear diffs. so make sure your diffs are properly shimmed, as they will die sooner.

 

[avogev]

You did all three or just the front ?

only center. it'll take care of ballooning and it'll accelerate stronger. turning wont change, even under full load since the front wheels will be spinning closer to the speed of the moving car which means they will actually have some grip instead of just doing burnouts on the front. wheel spin means grip is reduced. which is why in real cars, people try to not have the wheels spinning on takeoff since that really reduces the acceleration due to no grip on the surface. same concept here. front wheels are spinning faster than the car, means they are basically just 2 donuts covered in soap just sliding about. you can steer them fully to one side, and the car will keep going straight. go ahead try it before you change the fluid. maybe in midair it'll have a different effect, but thats an area i haven't had the bravery to explore yet.

someone mentioned that it'll effect driving over rough terrain or bumps. that is accurate since right now, with the light fluid, whichever axel loses the grip, thats the axel that gets a sudden burst of power. i have no idea if thats desired in a race, but doesn't sound good to me.

 

[Kevinbosch711]

only center. it'll take care of ballooning and it'll accelerate stronger. turning wont change, even under full load since the front wheels will be spinning closer to the speed of the moving car which means they will actually have some grip instead of just doing burnouts on the front. wheel spin means grip is reduced. which is why in real cars, people try to not have the wheels spinning on takeoff since that really reduces the acceleration due to no grip on the surface. same concept here. front wheels are spinning faster than the car, means they are basically just 2 donuts covered in soap just sliding about. you can steer them fully to one side, and the car will keep going straight. go ahead try it before you change the fluid. maybe in midair it'll have a different effect, but thats an area i haven't had the bravery to explore yet.

someone mentioned that it'll effect driving over rough terrain or bumps. that is accurate since right now, with the light fluid, whichever axel loses the grip, thats the axel that gets a sudden burst of power. i have no idea if thats desired in a race, but doesn't sound good to me.

Is it pretty basic to change the middle saw a YouTube video just worried about shimming?

 

[avogev]

Is it pretty basic to change the middle saw a YouTube video just worried about shimming?

shimming is needed because those internal parts in the diff spin pretty fast and from heat and friction eventually the oil leaks or the plastic wears away. when my diff fluid was changed, i noticed the diff was shimmed from the factory. maybe since mine is the latest model. but my differential was shimmed.

the other thing about the center diff is if you add thicker oil, the internal components don't move as much, resulting in that area not overheating or spinning as quickly against the plastic. so the shim isnt as necessary i think.

 

[Yonic]

@avogev, Well, I find it harder to accelerate while cornering with a stiff center diff, either the car “pushes” and understeers, or the rear accelerate so violently, it looses traction and overseers. With softer center diff the acceleration in the corners is so much for predictable.

And to clarify about the shimming, i’m wasn’t talking about the diff’s internal gears, but the input/ring gears of the diff (the gears on the outside). The front/rear diff will have twice the load if you put 500k in the center, as all the load of the car can be carried by the rear end when accelerating (or by the front end when breaking). With an open center diff, each end will be loaded only if the other end is having traction as well, meaning it’ll carry half the load only.

 

[Ari33]

@avogev, Well, I find it harder to accelerate while cornering with a stiff center diff, either the car “pushes” and understeers, or the rear accelerate so violently, it looses traction and overseers. With softer center diff the acceleration in the corners is so much for predictable.

And to clarify about the shimming, i’m wasn’t talking about the diff’s internal gears, but the input/ring gears of the diff (the gears on the outside). The front/rear diff will have twice the load if you put 500k in the center, as all the load of the car can be carried by the rear end when accelerating (or by the front end when breaking). With an open center diff, each end will be loaded only if the other end is having traction as well, meaning it’ll carry half the load only.

Yes, people need to be made aware of what they are doing and its possible effects. Thick centre diff oil absolutelywill be harder on the diffs and drivetrain but at least its not a fully locked centre diff that can easily cause diff problems especially with sudden sharp loadings after a jump for example.... where zero centre diff give due to 100% constant lock causes a huge instant shock to the drivetrain.

I've gone with 300k centre, I wouldnt go any higher and would probably be happy going down to 200k or even 100k for bumpy surfaces.
I know that drivetrain wear is likely to increase more than normal but quite comfortable with that and not expecting any explosions in my drivetrain anytime soon and I'm happy with not destroying my front tyres in one outing any more.

I thought 300k was quite a lot so 500k sounds a bit ambitious to me, be interesting to hear about drivetrain longevity over the long term from people who have done it.

 

[avogev]

Yes, people need to be made aware of what they are doing and its possible effects. Thick centre diff oil absolutelywill be harder on the diffs and drivetrain but at least its not a fully locked centre diff that can easily cause diff problems especially with sudden sharp loadings after a jump for example.... where zero centre diff give due to 100% constant lock causes a huge instant shock to the drivetrain.

I've gone with 300k centre, I wouldnt go any higher and would probably be happy going down to 200k or even 100k for bumpy surfaces.
I know that drivetrain wear is likely to increase more than normal but quite comfortable with that and not expecting any explosions in my drivetrain anytime soon and I'm happy with not destroying my front tyres in one outing any more.

I thought 300k was quite a lot so 500k sounds a bit ambitious to me, be interesting to hear about drivetrain longevity over the long term from people who have done it.

by that logic, cars that only have front and rear diffs should be failing twice as much. drivetrain load, i can understand, metal driveshafts should take care of those issues. but differential failure from a center diff being locked or absent alltogether, that i cant see. all it does is consistently deliver 50% power to the front and rear. i would even go as far as to argue that if the center diff oil is too light and the fronts lose grip and get 90% of the power, that would overheat and damage the front diff, bearings, dogbones (basically every front driveshaft component) alot more than a consistent 50% of a locked center diff.

 

[Ari33]

Center diff fluid 200k should be enough. Just remember when you thicken diff fluids(front and rear) it reduces your turning action. A thicker center diff fluid will give you good forward drive, but will be less forgiving.

I put 300k in my centre diff without touching the others, turning is still good due to the other 2 diffs still being relatively open. I get much less understeer on power than before and can also bring the back end round into play for big 4 wheel drifts now.

Thinking of increasing the front diff thickness a tad to stop the inside front tyre spinning up so much in the turns which should send a bit more power to the rear too. It will likely affect corner entry turn in but I need to experiment to find the handling I like for the surface I'm on.


I would absolutely love someone to bring out a REAL active centre diff for these things (Xrays so called active diff and the others not) Then we could program the centre diff to variably load and unload for any given throttle brake and steering parameter... 100% tunable car handling on the fly. I've looked into it but I don't have the resources or time to make a proper one. It certainly wouldnt be easy.

Maybe a micro ATB lsd type diff would be easier to manufacture. It works in the opposite way from a conventional diff in that it sends power to the wheel or axle with the most grip but doesn't lock the whole the whole front or rear axle like a torsen locking diff does.

https://www.quaife.co.uk/quaife-products/atb-limited-slip-differential/

by that logic, cars that only have front and rear diffs should be failing twice as much. drivetrain load, i can understand, metal driveshafts should take care of those issues. but differential failure from a center diff being locked or absent alltogether, that i cant see. all it does is consistently deliver 50% power to the front and rear. i would even go as far as to argue that if the center diff oil is too light and the fronts lose grip and get 90% of the power, that would overheat and damage the front diff, bearings, dogbones (basically every front driveshaft component) alot more than a consistent 50% of a locked center diff.

Fair points, I guess your right in some respects that the load would only increase to these proportions if both the front and rear diffs were also locked.
All I can say is that people who have fitted a spool (locked centre diff) to their buggies have destroyed front diffs before. I could point you to a few posts so maybe its an area of weakness when used outwith the standard diff oil specs.

Edit- Imagine landing front first off a jump with the throttle still pinned, lets say one tyre comes into contact with the ground first causing a sudden fast deceleration to its rotational energy to be transfered to both the other drive shaft and also the propshaft going to the centre diff. If the centre diff oil is really thick then far less energy can go in that direction and far more goes towards the driveshaft on the other side. That is the scenario I'd expect to see a gross overload of the front diff. Make sense?

 

[Yonic]

all it does is consistently deliver 50% power to the front and rear. i would even go as far as to argue that if the center diff oil is too light and the fronts lose grip and get 90% of the power, that would overheat and damage the front diff, bearings, dogbones (basically every front driveshaft component) alot more than a consistent 50% of a locked center diff.

No, locked diff transfer 50% to 100% of the torque, open diff transfer 0 to 50%.

If the fronts loose grip and all the power transfer to it, it doesn’t really strain, as it has no grip right?

 

[avogev]

Edit- Imagine landing front first off a jump with the throttle still pinned, lets say one tyre comes into contact with the ground first causing a sudden fast deceleration to its rotational energy to be transfered to both the other drive shaft and also the propshaft going to the centre diff. If the centre diff oil is really thick then far less energy can go in that direction and far more goes towards the driveshaft on the other side. That is the scenario I'd expect to see a gross overload of the front diff. Make sense?

that scenario is a really short second but yes, in that scenario, the front wheel without traction would get a ton of un-needed power and probably damage the front diff but it would need to happen long enough to get overheated. that scenario i can agree with being a case for center diff fluid thickness causing front diff harm.


@Yonic the fronts wont strain without grip, but it would get overheated. which will damage something plastic. but i don't think its a desired effect to just spin the fronts without grip and overheat the front diff, balloon the tires, lose the steering under load.


EDIT:

Actually now that i think about it, one of the latest videos from RCsaylors on youtube. they have a truck and they run it under full load. the fronts balloon and one of the tires even blows up. if you think about it, theses scenarios are far more common because under full load, and a turn, one of the wheels lifts off the ground at some point. and if you have the throttle pinned, that wheel gets basically way more power than its supposed to take, (that differential also). that scenario is a good example why thicker center diff oil is good. maybe in some technical races where you rarely go full throttle thinner oil is useful but i just cant see it in other cases. but anyone is more than welcome to school me.

 

[Ari33]

Actually now that i think about it, one of the latest videos from RCsaylors on youtube. they have a truck and they run it under full load. the fronts balloon and one of the tires even blows up. if you think about it, theses scenarios are far more common because under full load, and a turn, one of the wheels lifts off the ground at some point. and if you have the throttle pinned, that wheel gets basically way more power than its supposed to take, (that differential also). that scenario is a good example why thicker center diff oil is good. maybe in some technical races where you rarely go full throttle thinner oil is useful but i just cant see it in other cases. but anyone is more than welcome to school me.

It basically depends on what surface you run on. I noticed a huge change for the better on smooth tarmac after changing to 300k on the centre diff but when I tried hard acceleration on a bumpy loose surface it darted around in every direction and was hard to keep straight... where before with stock diff oil while it didnt get the same drive... it was a lot more controlable. Horses for courses...

Just try your buggy on a loose bumpy surface and you will see what I mean..

Dunno if you have seen this..

 

[Mike-NLD]

Damn.. Im reading a lot of 200k 300k 500k numbers..
For either a Talion, Notorious or a Outcast.. Wich come with 100k stock.. Well.. In that case its a raise of 200% to 500%
But the Typhon comes stock with just 10k.. So that makes it a raise of 2000% to 5000% !!!

 

[Ari33]

Damn.. Im reading a lot of 200k 300k 500k numbers..
For either a Talion, Notorious or a Outcast.. Wich come with 100k stock.. Well.. In that case its a raise of 200% to 500%
But the Typhon comes stock with just 10k.. So that makes it a raise of 2000% to 5000% !!!

The typhon comes with offroad track tyres that aren't quite as flat (across the tread) compared to a lot of other vehicles, the wheels are often smaller too... so the contact patch is generally much smaller in both directions for these various reasons. When you put road tyres on it the contact patch increases in the width direction but decreases a tad in the other but that combined with driving on a higher grip surface means these diff viscosities become too low, especially the centre diff.