41 replies to this topic

[Chris1992]

As Moke said - driveshafts would cause a vibration.

 

A wobble will be felt through the steering wheel but the car will physically move about.  A vibration will just be felt, but the car will still drive straight(ish).

A wobble can only really be caused by something that affects the steering/track alignment, so:

rack

track rods

steering arms

tie rods

wheels

subframe mounts

hubs

drive flanges

 

This has made me question the problem I have now, as the car still drives straight, but the steering wheels wobbles slightly from side to side at speed. Maybe I'm wrong though and what I'm feeling is a vibration. I've ticked everything off that list except drive flanges so that will be todays task as well as drive shafts and CVs 

[Bat]

 

while you are doing that, swapping the bearings over check the Drive flanges the taper washer and i would give the CVs (outer a once over) if you find nothing i would have a look at the inner CVs while the hubs are off. but there seemed little movement there are they would not really add to a wobble feel.

 

Ok will do mate, thanks. While examining the outer CVs, is there anything in particular I should look for? As in, what are the symptoms of knackered outer CVs?

 

Hi,

Sorry should have explained it better.

Have you got some behind the center of the wheel and some on the inner rim face?

There's more than one type of wheel balancing...

Cheers 

 

Ah right I see! All weights are on the inner barrel pushed up against the back of the face, so as close to to the center as possible if that makes sense? 

 

In that case go back and ask them to balance them properly! A computerised balancing machine will allow you to put weights just behind the spokes of the wheel and right towards the inner edge.

That should take the wobble out. All they've done for you is a "static" balance which stops the tyres wearing the heavy spot out first...

Cheers

Edited by Bat, 10 June 2018 - 12:01 PM.

[Chris1992]

In that case go back and ask them to balance them properly! A computerised balancing machine will allow you to put weights just behind the spokes of the wheel and right towards the inner edge.

 

That should take the wobble out. All they've done for you is a "static" balance which stops the tyres wearing the heavy spot out first...

Cheers

 

 

Oh really? I've never seen that done before! I'll add that to the list haha

[Chris1992]

Update. Last night at a car meet I met another mini owner, and as I was explaining the problems I'm having he offered to sell me a pair of complete driveshaft assemblies for 30 quid, so I figured whats the harm. Picked them up and fitted them this morning, and I do think it has made a small difference. One of my driveshafts was indeed quite bent, but after spinning the wheels on axle stands, I've noticed one of the replacements also has a slight wobble to it, but not as bad as the original. So the result is that the steering wobble has definitely reduced somewhat to the point I can drive the car without becoming enraged lol, but it's not fixed it completely. I may replace the slightly bent one and see if that cures it. I also examined the CVs and they all seem to be absolutely fine.

 

While the car was up in the air, I also idled it in gear with the wheels off so I could watch the hubs and flanges, and I observed a few things; firstly the drive flanges seem to be absolutely perfect with not even the slightest bit of run-out. However the part of the disk they mount to seems to wobble slightly. The disks themselves are pretty perfect, it's just the protruding part where the flanges mount that seems to be slightly off. would new disks be a logical next step? As the flanges certainly seem to be perfect. 

 

Cheers for everything so far guys, much appreciated. 

[nicklouse]

8.4 discs? they will have Zero effect on the feel of the car as they are only attached to the drive flange.

[Chris1992]

8.4 discs? they will have Zero effect on the feel of the car as they are only attached to the drive flange.

 

yes mate, 8.4 disks. They're now the only thing that hasn't been touched (other than swapping my old bearings back in, but I'll get to that). Might also take the wheels to another garage to be balanced again just for the hell of it.

[nicklouse]

well as i said it can not be the discs as even if they were missing you could still drive the car just not stop.

[Screwdriver]

I had my wheel balanced 2 weeks ago. After a strong wobble like you describe, I took it back only to find that the same balancing machine shared that the wheels remained out of balance. After a rebalance, the ride appears to be smoother. 

[scoop-deluxe]

[/quote]
In that case go back and ask them to balance them properly! A computerised balancing machine will allow you to put weights just behind the spokes of the wheel and right towards the inner edge.
That should take the wobble out. All they've done for you is a "static" balance which stops the tyres wearing the heavy spot out first...
Cheers [/quote]
Spot on. Static balancing is a waste of time, especially when chasing a vibration.
I would also throw away the aftermarket bearings and run some timkens. Thats a fair amount of wheel your running, makes everything work harder!

[Spider]

Update. Last night at a car meet I met another mini owner, and as I was explaining the problems I'm having he offered to sell me a pair of complete driveshaft assemblies for 30 quid, so I figured whats the harm. Picked them up and fitted them this morning, and I do think it has made a small difference. One of my driveshafts was indeed quite bent, but after spinning the wheels on axle stands, I've noticed one of the replacements also has a slight wobble to it, but not as bad as the original. So the result is that the steering wobble has definitely reduced somewhat to the point I can drive the car without becoming enraged lol, but it's not fixed it completely. I may replace the slightly bent one and see if that cures it. I also examined the CVs and they all seem to be absolutely fine.

 

While the car was up in the air, I also idled it in gear with the wheels off so I could watch the hubs and flanges, and I observed a few things; firstly the drive flanges seem to be absolutely perfect with not even the slightest bit of run-out. However the part of the disk they mount to seems to wobble slightly. The disks themselves are pretty perfect, it's just the protruding part where the flanges mount that seems to be slightly off. would new disks be a logical next step? As the flanges certainly seem to be perfect. 

 

Cheers for everything so far guys, much appreciated. 

 

Glad that you're making some progress here.

 

So when you changed the drive shaft, was that all that was changed, of did that also include swapping the outer CV Joint too?

 

When checking the drive flanges it would also be good to check the wheel studs are all on the same PCD (same radius), however the drive flanges may also need to be check while some weight on, though, if there's any movement here, it would show up on the tapered washer.

[Chris1992]

Spot on. Static balancing is a waste of time, especially when chasing a vibration.
I would also throw away the aftermarket bearings and run some timkens. Thats a fair amount of wheel your running, makes everything work harder!

 

Will any garage do proper balancing? What is the process called, as I've never heard of it. I assumed there was only one way of balancing! And I'll definitely splash out on timken bearings when I have the extra cash. Seems a shame as my current ones are brand new but ah well. 

 

 

 

Glad that you're making some progress here.

 

So when you changed the drive shaft, was that all that was changed, of did that also include swapping the outer CV Joint too?

 

When checking the drive flanges it would also be good to check the wheel studs are all on the same PCD (same radius), however the drive flanges may also need to be check while some weight on, though, if there's any movement here, it would show up on the tapered washer.

 

 

They were complete assemblies, so I also changed the inner and out CVs. I had a good look at them though, and both the new and old CVs seem to be perfectly fine. The Drive flanges do seem to be in good shape as are the studs, but I can see myself replacing them in future for piece of mind. I may also take various parts to a machine shop to be put on a lathe if the problem still persists. 

[Bat]

Hi,

Dynamic balance?

Tell them where you want the weights.

On the display on the machine they should have a cross section of a wheel rim and LEDs to show where the weights can go. A press of a button cycles through the different options available.

Cheers