Feedback on FSD Shocks and Non RFT's

[bassetm1]

Here is an interesting observation which I'm not sure is shared by many others. A while back I fitted Koni FSD shocks to my MCS (2005) while still having the runflats on. Car was transformed. Read my old post on this. Last week I scored a scew in my rear runflat so I replaced all the tyres with new non runflats. 215/40/17 Bridgestone RE001. Now you would think this would be the ideal setup to stop my Mini destroying itself over bumps but since fitting these new hoops I have returned to the ride quality pre FSD, ie standard hard as crap ride quality. Now before anyone starts ranting about 40 series tyres, the difference is so small relative to the 205/45, surley not enough to make them harder than runflats? My only other thought was maybe the FSD shocks are behaving differently with the different tyres???? Not what I expected really. Any comments?

[Dubcooper]

Having read every review going on the site I recall that the fsds can be sensitive to tyre pressure. Most recently in his excellent long term review on this forum Neurobeaker specifically pointed out;

Quote:

One thing I've found is that the ride quality is better when you keep your tyre pressures topped up properly, if the pressure drops then you don't hit bumps with enough force to allow the shock to do its special thing and travel - consequently, your ride quality worsens (becomes more harsh).

Might be worth checking the tyre pressures and experimenting with different values?

[bassetm1]

I did have a play with the tyre pressures for exactly the reason you mention. I tried 42PSI, hard ride becomes harder. Then I tried 30PSI, harder ride becomes slightly less hard. I am all out of ideas now and have decided you can't make a silk purse out of pigs ear (I think thats how it goes), the mini wasn't made for comfort and will wear the tyres out at track days. Its a shame really because the FSD shocks with the runflats was much nicer and ultimately quicker on real roads because of its extra compliance.

[jayxx83]

Try 34 psi front and 32psi rear. Have this on mine with 205/40/18 and it handles really well and ride is not too bad. I have standard shockers with Eibach springs.

[bassetm1]

Thanks, I'll try these pressures.

[jayxx83]

any joy with this?? has it made a difference for you?

[NeuroBeaker]

I'm interested to find out if you found a setup that worked for you - as, based on my experiences with tyre pressure, I would have thought good tyre pressures would have sorted it out.

On the issue of tyres... runflat tyres have more 'substance' to them - so presumably they'd be heavier. Could this account for some of the differences you're feeling? I would think a lighter tyre/wheel combination would move more in response to bumps, but overall I think many have previously found a more comfortable ride on conventional tyres.

It is a puzzling one...

All the best,
Andrew.