Front wheels making weird vibrations at full lock
 

Hi all.

I upgraded my front knuckles to aluminium which fixed my "turn sharper one way then the other" issue, but now at full lock I get a kind of "chugging" action on the front wheels.

I reduced the end points a fair bit until it stopped but now my turning radius is worse then my real car!!

Would this be the binding issue from using the stock shafts? Is the only way to fix this to upgrade to CVD'S or can I grind a bit off to get a bit more angle.

Money is tight so hoping for a "good enough" cheap option.

Thanks all.

Australia
SCX10 Honcho, Twin Hammers

Re: Front wheels making weird vibrations at full lock
 

If you are using a universal joint front axle its probably the universal beating itself up by adding more steering capability its hitting. If thats the case you can reshape the ends of the universal with a Demel.

Re: Front wheels making weird vibrations at full lock
 

Disconnect the drive shaft to allow the front to free-wheel. Turn full lock each way while looking to find where the issue is occurring. Once you understand where the issue is you can plan on steps to mitigate it.

You should be able to feel when it happens and then look at the associate parts. My bet is if you using the dogbone setup, the cogging happens every time the dogbone shaft meets the slot in the cup.

Sent from my XT1575 using Tapatalk

Re: Front wheels making weird vibrations at full lock
 

Yes, that's what it's called.. dog bones. I could not remember lol.

So I read somewhere I can grind a little bit off the cups to give the shafts more room at lock. I'll give this a try.

Thank you all for helping.

Australia
SCX10 Honcho, Twin Hammers

Re: Front wheels making weird vibrations at full lock
 

Normal, assuming you're not binding anything. U-joints, dog bones and RC CVDs (not true constant velocity joints) cause a change in speed as angle increases, the tire speeds up and slows down when you turn, even though the axle speed is the same. You can even feel this in a 1:1 4x4. This is also why drive shafts need to be in phase and have matching angles at each end, the two angles cancel out the change in velocity.

Re: Front wheels making weird vibrations at full lock
 

This is a basic understanding of what your driveline is doing. Pay attention to the angles in this video:"thumbsup"

Re: Front wheels making weird vibrations at full lock
 

That's a great video. So I'll check to see if my.dog bones are facing the save way and see if that makes a difference.

One thing I noticed is that the shaft itself is NOT touching the cup sides.

Australia
SCX10 Honcho, Twin Hammers

Re: Front wheels making weird vibrations at full lock
 

There's more than one type/style of constant velocity joint, the CVD's from MIP and similar style RC joints are a variation on the Tracta and Weiss joints. Although different from the Rzeppa and Tripod joints we typically see on cars, they're still constant velocity joints.

Re: Front wheels making weird vibrations at full lock
 

You can call them (MIP, VP, ect) constant velocity joints, but they aren't. They function just like a u-joint.

Re: Front wheels making weird vibrations at full lock
 

They reduce the vibration you get with a conventional u-joint, whether or not they fit your definition of CV-joint or U-joint is moot.