MG4 X Power Vibe/Hum 65 to 75mph

Sorry to dissapoint, but the damper is a damp sqib I'm afraid.

Has been tried and failed.

Still waiting for something definitive and proven from SAIC/MG.
Yeah, read that before. But that seems to all that is on offer according to my dealer. I suspect it's going to be a long wait for something that works.
 
For the record, we never fixed the vibe, we just took a 14-year vacation

(Hopefully Eagles fans will recognise the original quote.)
 
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Anyone have details on rotors for the xpower ? I am tempted to try as a possible fix. After all, they are not the same size as other MG4 models and as unique as the vibes
 
Anyone have details on rotors for the xpower ? I am tempted to try as a possible fix. After all, they are not the same size as other MG4 models and as unique as the vibes

Not seen anything this end.

Brake pads specifically for X Power are knocking about, but not seen Discs adverised anywhere yet.
 
Hello @Chikyu

Nice to hear from you!

I imagine that being in China you would have very easy access to spare parts like Brake Pads for X Power?

Would you be interested in supplying parts to the UK?

I would be very interested to know how much you are charged for parts for over there?

It could become a nice sideline for you if....

A. You are interested and
B. There is a viable saving to us (including fees and postage) that makes it worthwhile.

Just thinking out loud!

Just an example, X Power brake pads are
£275 GBP (¥2576)

That is very expensive!

I could buy Audi RS3 (2023) front pads made by Brembo for just £58! (¥532)

Be nice to hear what you think!

你好@Chikyu

很高兴听到你的消息!

我想在中国您会很容易获得 X Power 刹车片等备件?

您有兴趣向英国供应零件吗?

我很想知道你们那里的零件费用是多少?

它可能会成为你的一个不错的副业,如果......

答:你有兴趣,

B. 对我们来说,节省成本(包括费用和邮费)是值得的。

只是大声思考!

举个例子,X Power 刹车片是
275 英镑(2576 日元)

那是非常昂贵的!

我只需 58 英镑就能购买 Brembo 制造的奥迪 RS3 (2023) 前垫! (532日元)



很高兴听到您的想法!
Nǐ hǎo@Chikyu

hěn gāoxìng tīng dào nǐ de xiāoxī!

Wǒ xiǎng zài zhōngguó nín huì hěn róngyì huòdé X Power shāchē piàn děng bèijiàn?

Nín yǒu xìngqù xiàng yīngguó gōngyìng língjiàn ma?

Wǒ hěn xiǎng zhīdào nǐmen nàlǐ de língjiàn fèiyòng shì duōshǎo?

Tā kěnéng huì chéngwéi nǐ de yīgè bùcuò de fùyè, rúguǒ......

Dá: Nǐ yǒu xìngqù,

B. Duì wǒmen lái shuō, jiéshěng chéngběn (bāokuò fèiyòng hé yóufèi) shì zhídé de.

Zhǐshì dàshēng sīkǎo!

Jǔ gè lìzi,X Power shāchē piàn shì
275 yīngbàng (2576 rì yuán)

nà shì fēicháng ángguì de!

Wǒ zhǐ xū 58 yīngbàng jiù néng gòumǎi Brembo zhìzào de àodí RS3 (2023) qián diàn! (532 Rì yuán)



hěn gāoxìng tīng dào nín de xiǎngfǎ!
 
Anyone have details on rotors for the xpower ? I am tempted to try as a possible fix. After all, they are not the same size as other MG4 models and as unique as the vibes.
The vibration is not at the right frequency for the wheels or rotors to be the problem. I had a specialist NVH company test my car and the drivetrain itself seems to be the issue.

"The road test presented vibration consistent with a jarring of the drive-train, not like that experienced from wheel unbalance.

The Vibration Spectrums confirmed that the wheels were not out of balance or the cause of the vibration."
 
The vibration is not at the right frequency for the wheels or rotors to be the problem. I had a specialist NVH company test my car and the drivetrain itself seems to be the issue.

"The road test presented vibration consistent with a jarring of the drive-train, not like that experienced from wheel unbalance.

The Vibration Spectrums confirmed that the wheels were not out of balance or the cause of the vibration."
I agree. It is a significantly higher frequency than wheel balance. Although lesser in amplitude, it feels like running over rumble strips which would be oscillating at roughly 5-10 times per wheel rotation (wheel circumference is ~2m). I know nothing about the MG4 drive train but I would make a guess that the motor speed is reduced by around the same factor and the problem is one of imbalance within the motor.
 
I believe it is definitely front drivetrain harmonics causing this. I don’t believe it will be an out of balance motor as at 10000rpm+ (so way above the point where this vibration subsides), the whole vibration would just get worse and worse.

The wheels and tyres are acting as rotary dampers in effect, which is why different tyres and pressures (and even different road surfaces) have an effect on the level of vibrations.

I believe it is a complex design issue involving harmonics across the whole front drive train - any ‘fix’ SAIC are looking into involves trying to mask the vibration rather than fix.

Be interesting to see if the cyberster has the same issue as I understand it effectively has the front drive train from the x-power on the awd versions.
 
I've experienced this type of vibration with worn hardy spicer joints on prop/driveshafts - which essentially throws the shaft off balance, but I doubt this is a static balance problem. Might be interesting to try running with different tyre pressures left to right.
 
I believe it is definitely front drivetrain harmonics causing this. I don’t believe it will be an out of balance motor as at 10000rpm+ (so way above the point where this vibration subsides), the whole vibration would just get worse and worse.

The wheels and tyres are acting as rotary dampers in effect, which is why different tyres and pressures (and even different road surfaces) have an effect on the level of vibrations.

I believe it is a complex design issue involving harmonics across the whole front drive train - any ‘fix’ SAIC are looking into involves trying to mask the vibration rather than fix.

Be interesting to see if the cyberster has the same issue as I understand it effectively has the front drive train from the x-power on the awd versions.

Chaps, I don't know whether you have been back to the beginning? but check out my post #48.

I said driveshafts/driveshaft angle back then, (and the unusual harmonics that this 'may' cause) and I'm sticking with that til proven otherwise.

Post in thread 'MG4 X Power Vibe/Hum 65 to 75mph'

 
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Chaps, I don't know whether you have been back to the beginning? but check out my post #48.

I said driveshafts/driveshaft angle back then, (and the unusual harmonics that this 'may' cause) and I'm sticking with that til proven otherwise.

Post in thread 'MG4 X Power Vibe/Hum 65 to 75mph'


Yep have read from the beginning a few times and appreciate what you are saying.

The angle of the driveshafts shouldn’t cause this problem on its own. Many Lotus Elise owners have fitted Honda K20 engines to their cars which results far more extreme driveshaft angles than on the front of the x-power with no vibration issues. Agreed it’s far less than ideal and can lead to premature wear or failure of the joints down the line.

If it was the driveshafts themselves then it should just have been a batch QA problem plus if replacing them did solve the problem, this would be a relatively cheap and easy fix for SAIC to implement in the field.

This is why I believe it’s an overall interaction of several rotating components in the front drivetrain, hence more difficult to analyse and resolve without some serious design engineering input and potentially costly redesign implications.

What I still find staggering is how the car was signed-off as good to go by SAIC with this issue!
 
Yep have read from the beginning a few times and appreciate what you are saying.

The angle of the driveshafts shouldn’t cause this problem on its own. Many Lotus Elise owners have fitted Honda K20 engines to their cars which results far more extreme driveshaft angles than on the front of the x-power with no vibration issues. Agreed it’s far less than ideal and can lead to premature wear or failure of the joints down the line.

If it was the driveshafts themselves then it should just have been a batch QA problem plus if replacing them did solve the problem, this would be a relatively cheap and easy fix for SAIC to implement in the field.

This is why I believe it’s an overall interaction of several rotating components in the front drivetrain, hence more difficult to analyse and resolve without some serious design engineering input and potentially costly redesign implications.

What I still find staggering is how the car was signed-off as good to go by SAIC with this issue!

I know pal!!

I said it myself.

Who on earth were the development drivers?

Did any serious mileage get put on these cars in testing and at what speed?

The extremes to which every other car manufacturer punishes their cars before full blown production is mind boggling!

Perhaps that's why the cars are so cheap.....

They don't have an R and D section?

Just some bloke they 'Time Travelled' back from 70s British Leyland.

He just stands there with a small hammer for adjustments, fag in mouth, and has a quick look around before announcing.....
"That'll do"
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Eco on the highway mostly gone, somewhat liveable. Keeps me sensible too. MG and Dealer no care. I have to admit , I'm 98% of the time at non highway speeds.
 
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Well, well. The leasing company phoned me yesterday to say that my "steering damper upgrade" is available for my car and the dealer will call me to fix up a time for them to fit it. No call. I tried to call them but no answer left msg. for them to call me back. No call so far, CBA to chase them. :mad:
 
Well, well. The leasing company phoned me yesterday to say that my "steering damper upgrade" is available for my car and the dealer will call me to fix up a time for them to fit it. No call. I tried to call them but no answer left msg. for them to call me back. No call so far, CBA to chase them. :mad:
Leave a message on their facebook page but be careful not to post personal details.
 
Well, well. The leasing company phoned me yesterday to say that my "steering damper upgrade" is available for my car and the dealer will call me to fix up a time for them to fit it. No call. I tried to call them but no answer left msg. for them to call me back. No call so far, CBA to chase them. :mad:

Sadly it’s highly unlikely to make any difference too, although your vibrations sound worse than many so I guess it may have some impact.
 
I should add up front that the vibration in mine is not significant and most people probably wouldn't notice it. However, I did a bit of down and dirty analysis just to satisfy my own curiosity. Vibration was measured with an iPhone on steering wheel. I took two samples, one at 70mph and one at 75mph.

There is a small peak at wheel rotation speed which I would expect as no wheel is perfectly balanced but there is a much larger peak at 45Hz (@ 70mph) and then 48Hz (@ 75mph). This is what I feel through the steering wheel. Taking into account errors within my non-calibrated measurement I would take a punt that that the vibration felt is exactly 3 x wheel rotation speed.

Take from that what you will.

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