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Had a look at an MGF to replace my fathers current MGF which needs allot doing to it. The car we looked at had better paint, was in better condition and had the standard wheels. However there was a problem, even with the smaller standard wheels the ride was simply unacceptable.

It was better than my fathers, which is like a car on solid shocks, but it was still terrible. Even on a good road it found bumps, was jarring and crashed about. This on a car that is suppose to have a good ride. I know handling matters, but it is impossible to enjoy a car which is trying to reshape your spine.

To be honest I beginning to turn against the MGF and I am trying to persuade my father to look at a different car. The problem is by now the displacer units on these cars are getting old, many have lost their nitrogen. Pumping them up with more fluid to get back the ride height is a bodge, not a fix. If the fluid hasn't leaked out, it shouldn't need replacing. It is simply pressuring the suspension with fluid to replace the lost gas. Hence the jarring ride.

Do any MGFs ride properly on anything, but a dead smooth road? I can't imagine they were this bad new, otherwise reviewers wouldn't have praised the ride quality. Have I been unlucky in the cars I have sampled?

Had the same issue. A rock solid painfull ride. So took displacers out. Welded lugs, fitted valves and repressurised them. Soft ride now

Verstuurd vanaf mijn SM-G920F met Tapatalk

The problem is the nitrogen has gone and needs refilling but this can only be done by modifying the spheres and costs just under £500 and that will return your car to a drivable condition!
All f's will be suffering from this in various amounts

https://m.facebook.com/story.php?story_ ... 7798510522

For those not on facebook... Mike Saturs new product that is much cheaper than welding valves in and can be done at home... I'm going to give it a go and see

I have heard of the valve option, but I can still see a problem. it is essentially refurbishing old parts, spending that amount of money only for the displacers to corrode or the rubber membrane to go could be a painful experience. Thanks for the facebook link, I will take a look.

My first post was undiplomatic, but I do feel this issue isn't widely acknowledged enough. Most guides on buying MGFs in the classic car press completely ignore this problem and I have been surprised when speaking to owners at classic events how few are aware of the issue. The advice seems to be, if it sinks pump it up. Unaware that will not work if you do it too many times.

I think there is a bit of boiling the frog going on here. The slow decline in ride quality is going unnoticed, because it is slow. it becomes the new normal. The shame is nobody preserved the tooling for the suspension parts when production ceased. Hindsight is a wonderful thing.

I have seen a sphere that has failed and the reason it failed is low nitrogen!
They were originally filled in manufacturing from the top and the plug welded in protrudes!
So when the nitrogen gets low the membrane can get punctured giving you solid suspension.
As for all the rubber parts in the one I looked at they were not perished or deteriorated just a puncture hole.
But you are right it is a problem that has been ignored as there weren't any decent alternatives, but now there are at least a few options!

Have you considered a MGTF model year 2005. This had the comfort suspension which in my opinion is as good as if not better than the MGF. 2005 model year MGTF aren't common but worth investigating what's on the market for sale. They have the rear TF badge in the centre below the MG boot badge,which is the easiest way to i'd. one, but confirm by checking vin number. The advateges are are a younger car without the ageing 'F suspension though some consider the TF not as well built. They were also subject to Project Drive which was a cost cutting programme that saw the deletion of some components such as under bonnet light, cargo net in the boot, plastic covers on the engone cover grill, map pokets behind seats. Model year 2005 have benefits such as the comfort suspension, the low level coolant warning sytem, glass rear window and some with V spoke alloys.

ZSx wrote:https://m.facebook.com/story.php?story_ ... 7798510522

For those not on facebook... Mike Saturs new product that is much cheaper than welding valves in and can be done at home... I'm going to give it a go and see

I may buy some on payday too assuming there will be some left! Can you let me know hole diameters etc when you drill the hole and how you plan to extract the swarf that may go in while you drill?

I'm very excited for this as it really changes the game for those who don't want to do a swap to coilovers

David Dixon wrote:Have you considered a MGTF model year 2005. This had the comfort suspension which in my opinion is as good as if not better than the MGF. 2005 model year MGTF aren't common but worth investigating what's on the market for sale. They have the rear TF badge in the centre below the MG boot badge,which is the easiest way to i'd. one, but confirm by checking vin number. The advateges are are a younger car without the ageing 'F suspension though some consider the TF not as well built. They were also subject to Project Drive which was a cost cutting programme that saw the deletion of some components such as under bonnet light, cargo net in the boot, plastic covers on the engone cover grill, map pokets behind seats. Model year 2005 have benefits such as the comfort suspension, the low level coolant warning sytem, glass rear window and some with V spoke alloys.

We've had a MY2005 from new - yes the springs are softer and dampers a bit better than older TFs but the ride was still awful in comparison with a good F. This suspension carried on into the Chinese ones from 2008 so these wont be any better. The 85th Anniversary however had Bilstein shocks and is a different car. I changed our shocks to Bilsteins and the car was transformed completely.

Disagree with you comments about the ride being awful on model year 2005 MGTF. All my 3 MGF's, an MX5 NC and my current MGTF i have taken on the Evo Triangle, clock and anti clock. (so named as Evo Magazine regularly road test cars on the roads). This a good test of car and suspension, and my previuosly owned MGF Trophy and my current MGTF were on a par, but in differing ways.

ZSx wrote:https://m.facebook.com/story.php?story_ ... 7798510522

For those not on facebook... Mike Saturs new product that is much cheaper than welding valves in and can be done at home... I'm going to give it a go and see

I'd be leary of Mike Satur's valves for several reasons: Mike states that his valves are rated for 500 psig, which just isn't high enough. The valves need to be rated for 59 bar (855 psig), which is the maximum working pressure of the sphere stamped on it by Dunlop. When the F's suspension is is pumped up to the correct height, the system is pressurised to 400+ psig. When you are driving and the suspension is absorbing the bumps in the road, its easy to imagine that the nitrogen pressure will exceed 500 psig. If the nitrogen portion of the sphere gets compressed to half it's volume absorbing bumps, then you are at 800 psig.

Secondly, the metal thickness of the sphere is approximately 3 mm. I'm not convinced that a valve can be threaded into 3mm of material tight enough to remain pressure tight for pressure approaching 855 psig. My mistake in terms of attachment method.

If you look at a Citroen Sphere, which is their equivalent of the Hydragas displacers and have always been re-chargeable, you will see that the valve has a thread length of about 6mm. And Citroen should know what they are doing, after all, they've been using their Hydropneumatic system since the 1940s.

Thanks Barry for this information. It makes me feel even more sure that 3mm of thread isn't enough. My mistake in terms of attachment method.

mowog73 wrote:Thanks Barry for this information. It makes me feel even more sure that 3mm of thread isn't enough.

If you read Mike's description of the product you will see that it is not threaded into the sphere- he makes no reference to this! It is retained in a similar(but not identical) way to a car wheel schrader.

Thanks John for pointing out my error. When I read Mike's description Sunday morning I misunderstood the attachment method. But I do stand by my comment that the valve needs to be rated for the maximum working pressure of the sphere.

mowog73 wrote: But I do sand by my comment that the valve needs to be rated for the maximum working pressure of the sphere.

Does anyone know anything further to this? I am planning to buy a set but acknowledge that 500psi is the max pressure and the system can get up to 800 but then I've seen people saying they've used standard valves up to 1000psi (most of the info I could find was actually on a forum about pneumatic spud guns lol) so I'm assuming that these valves rated at 500psi could cope with the occasional rise to 800ish? Not my area of expertise just trying to make sure there won't be any issues before purchasing

Would Mike Satur offer this if he didn't think it would work?

I very much doubt it I spoke to him about these a few weeks back and I can't imagine he wouldn't be using them if they weren't fit for purpose. I just didn't know if he had explained it to anyone during conversation and took a quick look online that confirmed the valves should cope easily

Personally I'm ordering mine tomorrow and am very, very excited to get the ride quality restored I have one available to me spare so I pray if any are ruptured it's not more than one, no leaks but still a risk of a burst diaphragm, be nice if it was at the front if it has to happen

I really need to get mine sorted and this appears to be a cheaper option than the other place that does them all for £380. Not sure I could fit them myself so I'll be interested on how you get on if you do manage to fit them. I may just buy them anyway

hammond wrote:I really need to get mine sorted and this appears to be a cheaper option than the other place that does them all for £380. Not sure I could fit them myself so I'll be interested on how you get on if you do manage to fit them. I may just buy them anyway

If you have a honest local mechanic I doubt they'd charge over the odds, installation is effectively depressurise the hydragas; drill 4 holes and screw the valves in, then all you need to do is test with air then get filled with nitrogen before depressurising the fluid so can't be more than an hour or two labour it's just finding somewhere than can pump nitrogen to 280psi