Wheel Wobble

[Farmers00]

Hey guys,

Its my first time posting and I have a quick question. I just finished adjusting the steering and installing the front diff locker from Vaterra on my Twin Hammers. Now when I turn the wheels right or left while moving, there is a very strange wheel wobble that makes the whole truck shake. When I am going straight at any speed theres no issue. Prior to my adjustments and front diff lock there was no issue.

As this is my first experience with front locked diff, is this normal? or is it something I did?

Thanks!

 

[foratm]

That's mostly because of the locker and the loose steering slide that is on the set up. Personally I would take the locker out and put in 500k weight diff fluid. Less parts will brake and it had worked just as good as locking the front in my opinion.

Sent from my MB855 using Xparent BlueTapatalk 2

 

[Farmers00]

Thanks Foratm! I was worried i did something wrong. My first time doing anything mechanical on an RC. I was weighing the options between the locker and the 500k oil and just decided to get the locker since I'm not going to do any racing or quick turns anyway. Lets see what I can break!!

 

[zanthrax]

Mine had a wobble on two wheels, I fixed it by removing the bead locks and reinserting the foams. Make sure the foam is in the center groove of the wheel when remounting everything. Mine weren't before, after remounting the wobble is gone.

 

[Farmers00]

The main issue is that it does it in the air too. My tires are a bit out of round probably due to foams, but it doesn't wobble while going straight only when I'm turning. It's like it's binding on something. But I can't see what it would be binding on. Had no problems until I installed the front diff lock. I'm pretty sure I put everything back together properly. I didn't even remove any suspension links. Just unhinged the lower front control arms or a frames w/e. when I was done I just slid the dog bones back into place, reattached the lower arms with the pin and screwed the diff back together and the front aluminum brace thing hat holds the pins in place. Goes fine in a straight line but once I turn the wheels it gets a death wobble/bind. I can't imagine the locker being the culprit here as it works just fine with no steering applied.

 

[Farmers00]

Here is what its doing.
Twin hammers wobble - YouTube

 

[Stollenritter]

Hello Farmers,

Rotate one wheel by hand while the wheels are straight, then turn the wheels (with electronics off, just by hand) while still rotating the wheel (wheels have to be off the ground). Maybe you can feel resistance at some point when starting to turn the wheels in one or either direction.
When you feel resistance, take a closer look at the drivetrain, maybe something is binding. Parts of the drivetrain where apart during installation of the front locker, so something could have gone wrong during reinstallation. Hope this helps.

Stollenritter

 

[zanthrax]

That wheel wobble with wheels in the air, on full steering lock comes from the dogbones almost falling out of the drive cups on the front diff. Shorting the suspension links a little should help.
You'll also see that the wobble gets less when the suspension is compressed.

 

[Farmers00]

Rotate one wheel by hand while the wheels are straight, then turn the wheels (with electronics off, just by hand) while still rotating the wheel (wheels have to be off the ground). Maybe you can feel resistance at some point when starting to turn the wheels in one or either direction.
When you feel resistance, take a closer look at the drivetrain, maybe something is binding. Parts of the drivetrain where apart during installation of the front locker, so something could have gone wrong during reinstallation. Hope this helps.

No real resistance. If i ease on the throttle and keep it very slow the binding / vibrations arent noticable.

That wheel wobble with wheels in the air, on full steering lock comes from the dogbones almost falling out of the drive cups on the front diff. Shorting the suspension links a little should help.
You'll also see that the wobble gets less when the suspension is compressed.

I compressed one of the control arms and did the same turning and throttle motions and it still had some wobble. I took both front wheels off and the wobble went away. So then i thought maybe it is the foams being off center. So i took the foam out of one wheel and put the beadlock back on but I still get the vibrations. I dont notice it as much when its driving but i think thats just because its bumpy anyway. I would have to assume that the front diff locker is the culprit but it seems weird to me that it does it in mid air.

I also gave it a better once over last night and nothing i can see is binding. In fact if i had to assume a binding position, it would seem its comming from the u joint on the wheel side where the half shaft or what ever its called connects to the part of the wheel that turns right or left. Sorry for my lack of correct terms.

 

[foratm]

That is definitely not what I originally thought after watching it wobble.

Sent from my MB855 using Xparent BlueTapatalk 2

 

[Farmers00]

Any ideas? Is it wheel balance? Or just the way the front locker works?

 

[hlrider130]

Try backing the dual rate off a little an see if that helps

 

[Farmers00]

Oh so I should turn down the steering sensitivity? Maybe the wheels are turning too sharp? Sorry i am a bit of a noob and still learning.

 

[hlrider130]

Yea exactly. Other than that I'm at a lost.

 

[eddiekfx]

camberg the wheels a bit it helped me

 

[LukeKang77]

Hey guys,

Its my first time posting and I have a quick question. I just finished adjusting the steering and installing the front diff locker from Vaterra on my Twin Hammers. Now when I turn the wheels right or left while moving, there is a very strange wheel wobble that makes the whole truck shake. When I am going straight at any speed theres no issue. Prior to my adjustments and front diff lock there was no issue.

As this is my first experience with front locked diff, is this normal? or is it something I did?

Thanks!

I was having the same issue with mine after I installed the front locker, wobbles and binds up at full turn. I removed my front wheels and found that the CVD's where rubbing on the front spindle knuckle hubs. I had to Dremel a little material away. I can't say for sure that is your issue, but worth checking.

 

[Farmers00]

That sounds like the same problem I am having. It looks like its binding up at the wheel side of the CVD. Ill take a look.

Thank all for the replys.

 

[iacdmac]

That sounds like the same problem I am having. It looks like its binding up at the wheel side of the CVD. Ill take a look.

Thank all for the replys.

Did this fix your trucks wobble? I took the locker out and fixed the tire foams and still am having the problem although not as bad since I took the locker out.

 

[Farmers00]

I'm gonna have a crack at it tonight. I also fixed my steering so it would turn more evenly and sharp to the point where it would get full lock. Its entirely possible that the truck doesn't like to turn that sharp and causes binds at the wheel. So i'm gonna turn down the steering sensitivity on the controller and see if that helps it out. from watching other crawling videos, their wheels don't turn nearly as sharp and I got mine to, so it would seem logical. I'll post my findings tonight.

 

[iacdmac]

I'm gonna have a crack at it tonight. I also fixed my steering so it would turn more evenly and sharp to the point where it would get full lock. Its entirely possible that the truck doesn't like to turn that sharp and causes binds at the wheel. So i'm gonna turn down the steering sensitivity on the controller and see if that helps it out. from watching other crawling videos, their wheels don't turn nearly as sharp and I got mine to, so it would seem logical. I'll post my findings tonight.

Yea I adjusted my steering to be really sharp and at the same time fixed that problem where the servo would lift up so maybe its just the fact that we both have the turning radius to sharp.