Wheel wobble / vibration

[Andrew S]

Sorry this is long but .......

OK, I have been trying to find out the vibration problem on the Stag that comes in from 15mph and sort of goes away after 50mph. All wheel were balanced last weekend and I have gone back to basics to try and find the route of the cause. I therefore jacked the car up and ran it on axle stands with the front chocked.

Sitting in the car and running the 1st and 2nd gear, the vibration comes in at 15mph as the same as when driven. It is clearly noticeable when sitting in the car as when you reach the 15mph onwards, the car seems to want to bounce as if going over those yellow stripes you get before you reach a roundabout. Only the offside wheel turns as expected being that both wheels are off the ground.

When I remove the wheel and test again, the problem goes, therefore the problem is in this area.

You can see the wheel running out in the following clips

https://youtu.be/JZS2Mh_k46s

https://youtu.be/JKdJcK9jFC0

https://youtu.be/xxr_75a3tGQ

I then put the spare wheel on and I have the same problem as can been seen below. This spare wheel has a brand new tyre and never been used, although not balanced.

https://youtu.be/MZ0AFV53nsY

https://youtu.be/msqx5CqlB0U

https://youtu.be/mZplXNg5Za0

I then put a pointer against the rim to see if there was any run out. There is some as can be seen below

https://youtu.be/TPQXgRMTl3c

I then removed the wheel and looked to see if there was run out against the drum on both sides as below

https://youtu.be/ef0HD-ViCrw

https://youtu.be/j4FtpcAZfdc

https://youtu.be/vSET0b1hFCY

Then I removed the drum to see if there was run out on the drive shaft flange. There is slightly but not sure if this is the problem.

https://youtu.be/C-XHpRChEwY

My problem is that I dot know if its the driveshaft flange out, the wheels but odd that it would be both wheels or the tyres which are the same make, one being new.

Wheels were fitted using 2 tapered steel road wheel nuts as always to centralise the wheel before fitting the stainless steel nuts. So I am happy that the wheel is located correctly on the studs.

I will ask my local Stag owners to borrow a pair of wheels to test tomorrow but for now, I am puzzled and hoping any of you have an opinion on what you can see in the clips. Even after fitting another set of wheels, if that cures it, then I still wont know if its the wheels or tyres. I could buy a new set of tyres and find it hasn't cured anything

Really sorry that this is long but sometimes seeing is better than reading

Thanks for any comments or advice as this problem is really getting to me now

Cheers
Andrew

[Bazstag]

Have you tried another set of drums? also, has the propshaft come out of balance?
Baz

[Andrew S]

Hi Baz, I forgot to mention that I fitted the wheel without the drum and it was the same. Prop u/js I replaced as a matter of course but problem was there before.
Thanks for your comments
Andrew

[Andrew S]

Hoping to try out another pair of wheels on the back of the car in particualr the offside rear as looking at the footage I took as above, I am almsot convinced its my tyres even though one is brand new. Of course may be wrong and its the drive shaft flange but when I look at the wheel turning in the film, it looks more the case that the wall of the tyre is not true and despite balancing the tyres, it is giving me a wobble and would be worse under driving conditions.

If it is the tyres then I will be joining some others in the multiple world of tyre sizes or even wheels

Fingers crossed for good weather at the weekend

[wilf]

Perhaps (just perhaps), you have both an out of round wheel and tyre, and the position the tyre is fitted in is exacerbating the run out. You could try having the tyre dismounted and remounted 180degress around.

Cheap, anyway.

[Andrew S]

Thanks Wilf, good suggestion but its the same on the day to day wheel and the spare, so it should either be the hub or the make of the tyres. The hubs were refurbed 5 years ago

[marshman]

Looking at your youtube videos I'm not sure that I have saw anything that I would regard as excessive in terms of either wheel or tyre "wobble". I have my own tyre changer and wheel balancer and have balanced many wheels off of older cars - especially 50's and 60's with steel wheels and I would say they are all worse - a lot worse than yours. Some look so bad on the wheel balancer that I fully expect them to be unusable on the car but they have always been OK.

Another point is that if it comes in at 15MPH how fast is the "vibration" if it is a distorted rim/tyre it will by at quite a low frequency almost to low to be called a vibration. At 15MPH it will be around about 7Hz (7 wobbles/vibrations per second)

Calculated as follows: circumference of tyre approx 2m. 1609m per mile. 15mph = 24140 meters per hour divide by 3600 to give seconds = 6.7 revolutions of the wheel per second at 15mph.

At 50mph it is around 22Hz or wobbles/vibrations per second.

Do those numbers tie up with what you are feeling?

Roger

[Guest]

Not sure if I understand all the technical stuff?
All I will say is.. I had a vibration on my car when I bought it, I changed the wheels and tyres and the problem went. I had 2nd hand wheels and new tyres.
Hope this of some help?
Steve

[Andrew S]

Looking at your youtube videos I'm not sure that I have saw anything that I would regard as excessive in terms of either wheel or tyre "wobble". I have my own tyre changer and wheel balancer and have balanced many wheels off of older cars - especially 50's and 60's with steel wheels and I would say they are all worse - a lot worse than yours. Some look so bad on the wheel balancer that I fully expect them to be unusable on the car but they have always been OK.

Another point is that if it comes in at 15MPH how fast is the "vibration" if it is a distorted rim/tyre it will by at quite a low frequency almost to low to be called a vibration. At 15MPH it will be around about 7Hz (7 wobbles/vibrations per second)

Calculated as follows: circumference of tyre approx 2m. 1609m per mile. 15mph = 24140 meters per hour divide by 3600 to give seconds = 6.7 revolutions of the wheel per second at 15mph.

At 50mph it is around 22Hz or wobbles/vibrations per second.

Do those numbers tie up with what you are feeling?

Roger

Thanks Roger, interesting. When I say vibration, its more of a pulsating drone. There is side movement on the tyre wall as can be seen but more importantly, the tyre moves off centre as if not correctly on the studs or the wheel is off centre. I can feel the car wanting to bounce when the wheel is on and so when on the road, this must have an impact, especially on load. I agree that side movement can be ok if tyres are balanced but this is more than that but cant really be seen in the film clips.

Thanks for your feedback and that impressive calculation

[Andrew S]

Not sure if I understand all the technical stuff?
All I will say is.. I had a vibration on my car when I bought it, I changed the wheels and tyres and the problem went. I had 2nd hand wheels and new tyres.
Hope this of some help?
Steve

Thanks Steve

[LAMBRETTLAD]

I have had my wheels balanced to zero three times ,each time it moved the wheel wobble up or down and the vibration to different frequencies,but still much better than when I first got the car ( it would shake your teeth out ,so I have have to suck it and see :roll eyes.
I haven't been able to take the new wheels over 40 mph,yet but fingers crossed ????????.
Going to a scooter rally this weekend

[marshman]

How old are the tyres? (appologies if you have already told us). I ask because if they are old(ish) the rubber may have hardened up and the drone and vibration could be caused by the tread. Did it make any difference if you swapped wheels front to back?

I understand what you say about off centre movement with the tyre/wheel going up and down but again I have seen this to quite high levels on the wheel balancer and also when spinningwheels by hand on the car with no apparent effect.

The real clincher would be to swap all four wheels and tyres with those from a known good car. If it is your wheels and tyres then it should affect the other car.

Roger

[Andrew S]

Hopefully Roger that's what I hope to do at the weekend or early next week. I may be totally wrong and going down the wrong route but if the drone / vibration goes if on axle stands with the rear wheel removed, then is there immediately after refitting the wheel, it must be the lowest common denominator?

[flying farmer]

I think the clue here is that you said the hubs were rebuilt 5 years ago. I would bet that the mounting flange got bent when it was done.

The usual Stag alloy problem is that the wheel wobbles in a vertical plane, not a horizontal one, and the fact it does it several wheels just confirms that.

A tiny bit of run out on the hub will be magnified by the diameter of the wheel.

Neil

[Andrew S]

I think the clue here is that you said the hubs were rebuilt 5 years ago. I would bet that the mounting flange got bent when it was done.

This is a good point. I have had this problem for many years and as part of the potenial resolution was that the hubs were rebuilt. I had to send them away and it took around 10 days to get a pair back. Could well be that the ones I got back were my old faulty ones anyway.

Not sure why I have not done this yet but I have focussed on the offside rear wheel wobble but havent looked at the nearside. To possibly rule out either hub or wheels, all I need to do is to jack up the nearside and run through the gears again with the same and tyre and see if it wobbles.

Neil, I have vertical and horizontal movement

Thanks
Andrew