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** Hey all, I just wanted to know if anyone in Melbourne, has some unmounted 15\" tyres I can borrow for a day or two?? I want to fit them to my Simmons, get them balanced and go for a quick drive, to see if its my crappy tyres casing the bad balancing/vibrations.

If anyone in Melb can help me out I would appreciate it very much**


Hey guys,

I just need a bit of help regarding the 15\" Simmons i recently fitted to my car. I noticed when I first fitted them, and went for a drive that at 70kmh and up the steering wheel would shake from side to side (pretty bad). Then at 100kmh and up the whole car would vibrate, until I slowed back under 100kmh.
I inspected all of the wheels and found one that was warped, so I sent it away to get fixed. I picked the fixed wheel up on Friday, it was perfect not one bit of movement. Then early Saturday morning I went to get the tire re-fitted to the wheel, and also to get all four wheels balanced.

The guy who balanced them said they were shocking to balance, and that they needed heaps of weight (the worst was 175g/80g. I have never seen that much weight on a wheel.). I asked him if any of the rims were warped and he said they are all spot on, so the tyres must be stuffed. Even the one that was repaired and running perfect needed alot of weight to balance it out.

With the wheels all balanced I went to another drive, and found that the side to side wheel movement had gone (would have been the warped wheel on the front), and that the car is nice and smooth until 105kmh then the car vibrates quite bad, and the steering wheel starts to shake. It gets worse the faster you go....

My question is could the tyres be causing this bad balancing/vibrations? The other wheels/tyres I had on before the Simmons were fine at all speeds, and never vibrated. Having talked to all the guys at the wheel shop they were convinced it was the tyres causing the bad balancing, but would they vibrate even after they are balanced.

I just want to try and pin point the problem before I go spending money on tyres, to find the car will still vibrate.

Wheels: Simmons 15x7 +35
Tyres: Cheap ass Doral somethings. (came with the wheels, have 75% left) 195/50 15.
Tyre pressure: All four at 32psi

Any help is very appreciated.

Cheers
Ryan

green_comet wrote:My question is could the tyres be causing this bad balancing/vibrations?

Yes. I had a similar problem with Firestones on an MGB. Could not balance the mongrels at all. I was going to replace the (wire spoked) wheels but changed tyres to a set of Yokos - problem gone instantly.

I had a wheel that couldn't be balanced once. The tyre shop rotated the tyre on the wheel a little and all was fixed. Their explanation was that the tyre had a high spot on it that correlated with the high spot on the rim.

green_comet wrote:My question is could the tyres be causing this bad balancing/vibrations? The other wheels/tyres I had on before the Simmons were fine at all speeds, and never vibrated. Having talked to all the guys at the wheel shop they were convinced it was the tyres causing the bad balancing, but would they vibrate even after they are balanced.

Yep, tyres can do that. Had my 7 year old Yokos replaced with Adrenalins and the 110kph vibrations disappeared. No matter how much I had the old Yokos balanced, it still caused some vibrations, albeit small. Now gone!

Thanks for the help guys.... I was going to replace the tyres with a set of Adrenalins in the future, looks like ill have to get it done in a week or two instead.

Cheers
Ryan

Hey Ryan, I think I spoke to you about this the other day. I had the same problem and I was about to get different tyres but when I took it to get balenced they suggested hub locaters. Doesn't sound like it would do a huge amount but it got rid of my vibration which makes me happy

Ben

Are all mx5 hubcentric??

meanmx wrote:Hey Ryan, I think I spoke to you about this the other day. I had the same problem and I was about to get different tyres but when I took it to get balenced they suggested hub locaters. Doesn't sound like it would do a huge amount but it got rid of my vibration which makes me happy

Ben

Yeah I was thinking about hub locaters too Ben, but I think if it were that the wheels wouldnt have balanced soo badly.. Im thinking it could even be that the tyres were rotated on the rim, and now they are in a different position relative to the rim and they are out of round..

If you have access to a spare set of non bent rims, mount the tyres in question on those rims. Should tell you whether not the tyres are an issue.

I have a set of rims but they are 14\", Ill have to try get my hands on a set of 15\" tyres from someone, fit them to the Simmons and go for a drive.

Is anyone in Melb able to help me out, by lending me a set of 15\" tyres?

well i don't have any unmounted 15\" tyres or wheels. hopefully someone else can help you out. but if no-one else comes forward to help you out in the next day or 2 , i can take my 15s off the car and run on my 14s . you will just need to unmount the tyres (c drives), then remount when you return them to me. it's not an ideal solution tho, preferably someone else can help.

Thanks for the offer James, Ill let you know how I go..

1. Have you tried jacking up your car and rotating the wheels on your hubs to see if they don't wobble left/right or up/down?

3. Are you confident that your tyre place did mount the offending wheels correctly on the balancer when they balanced them?

manga_blue wrote:1. Have you tried jacking up your car and rotating the wheels on your hubs to see if they don't wobble left/right or up/down?

3. Are you confident that your tyre place did mount the offending wheels correctly on the balancer when they balanced them?

i'll put a 2. in .............another dumb thing that a lot of hack tyre guys do is to try & balance wheels with the old weights still on them............that buggers things too

AJ wrote:

manga_blue wrote:1. Have you tried jacking up your car and rotating the wheels on your hubs to see if they don't wobble left/right or up/down?

3. Are you confident that your tyre place did mount the offending wheels correctly on the balancer when they balanced them?

i'll put a 2. in .............another dumb thing that a lot of hack tyre guys do is to try & balance wheels with the old weights still on them............that buggers things too

2. There is no point 2.