Removing Runflats - 125i M Sport
Discussion
Hi All,
It's reached that unpleasant part of the year where the 125i is about the need new tyres - after 40K of having my fillings jostled by the OEM Bridgestone Runflats I've decided it's time to get rid and put some normal tyres on - I have family who work for Michelin so will have to go down this route, so was looking at the new Pilot Sport 4's, but from the looks of things they aren't available in the default size for rears of an E82 M-Sport - 245/35 R18's. I've noticed I can get 255/35 R18's, has anyone ever tried going for 225/40 on the front and 255/35 on the rear?
Am I likely to encounter any issues with rubbing? It has 208M's on currently.
It's reached that unpleasant part of the year where the 125i is about the need new tyres - after 40K of having my fillings jostled by the OEM Bridgestone Runflats I've decided it's time to get rid and put some normal tyres on - I have family who work for Michelin so will have to go down this route, so was looking at the new Pilot Sport 4's, but from the looks of things they aren't available in the default size for rears of an E82 M-Sport - 245/35 R18's. I've noticed I can get 255/35 R18's, has anyone ever tried going for 225/40 on the front and 255/35 on the rear?
Am I likely to encounter any issues with rubbing? It has 208M's on currently.
After a quick chat with Black Circles they suggested that the 225/255 combination will be a good fit for the car, so I have 4 Michelin Pilot Sport 4's on order to be fitted on Saturday.
This has led me to the next question - the spare wheel. I've been generally advised to go down the tyre sealant route, but from the looks of things the standard gunk makes the tyre useless after it's been used - has anyone tried Ultraseal?
http://www.ultrasealgb.co.uk/site/
This has led me to the next question - the spare wheel. I've been generally advised to go down the tyre sealant route, but from the looks of things the standard gunk makes the tyre useless after it's been used - has anyone tried Ultraseal?
http://www.ultrasealgb.co.uk/site/
bodhi said:
After a quick chat with Black Circles they suggested that the 225/255 combination will be a good fit for the car, so I have 4 Michelin Pilot Sport 4's on order to be fitted on Saturday.
This has led me to the next question - the spare wheel. I've been generally advised to go down the tyre sealant route, but from the looks of things the standard gunk makes the tyre useless after it's been used - has anyone tried Ultraseal?
http://www.ultrasealgb.co.uk/site/
This has led me to the next question - the spare wheel. I've been generally advised to go down the tyre sealant route, but from the looks of things the standard gunk makes the tyre useless after it's been used - has anyone tried Ultraseal?
http://www.ultrasealgb.co.uk/site/
'Standard gunk' doesn't make a tyre useless, I've cleaned and repaired one of my own tyres this year after using the stuff. It didn't work by the way, failed after about 5 minutes and had to be recovered home. Most tyre shops can't be bothered cleaning the s
t out and no one has the time to wait for the tyre to dry after, that's why they all say the tyres useless. Ultraseal's little better than 'standard gunk' though someone will be along soon to deny that. Though even he's stopped using it now......
IMO runflats aren't too useful anyway, 50 mile range isn't that much real use, though it gives some reassurance if my wife's out on her own. I've started carrying plug repair kits, a couple of tools and a 12v compressor. Would have worked in my case earlier this year and saved me a lot of time.
Just thought I'd update, had 4 x Michelin Pilot Sport 4's fitted on Saturday, going for the 225/255 option as mentioned. Pretty sure I brought someone else's car back from ATS, these tyres are an absolute revelation. Ride is completely transformed, rather than crashing over everything, it glides, even over those viscous small black and yellow speed bumps that used to induce much wincing. Grip seems even better than it was before, tyre noise is massively reduced, and wet grip is astonishing. did 100 miles in the monsoon on Monday, zero issues with standing water whatsoever.
I have had to take the car back to ATS as the front right was losing pressure, turns out the tyre wasn't seated properly. It was sorted with no quibble, so no complaints.
Best thing I've ever done in a car tbh.
I have had to take the car back to ATS as the front right was losing pressure, turns out the tyre wasn't seated properly. It was sorted with no quibble, so no complaints.
Best thing I've ever done in a car tbh.
Can you please tell me if ditching the runflats has made the steering on your car lighter?
The reason I ask is that I've recently driven a BMW X1 2013 model which had runflats on and the steering was very heavy. Just wondering if changing to normal tyres will help eradicate the heavy steering.
The reason I ask is that I've recently driven a BMW X1 2013 model which had runflats on and the steering was very heavy. Just wondering if changing to normal tyres will help eradicate the heavy steering.
CypherP said:
Is this change something that needs to be disclosed to an insurance company? I'm considering doing the same on my 640d because the ride is shockingly hard, but am interested to know how this might affect insurance cover?
Varies from insurance company to insurance company. Best to give them a call and check, jut to be on the safe side.I've never had an insurance company change a premium for ditching the runflats, as long as i stuck with standard sizes.
Craikeybaby said:
I swapped wheels front to back on my E87 the other day and I was surprised at just how heavy the 16" wheels with runflat tyres were. Significantly heavier than the 16" wheels on the back of my MR2.
On my old R53 Cooper S, the runflat tyres were 2.5kg heavier than normal tyres in the same size ...per wheel.So switching to runflats saved 10kg weight overall
When moving from RF's I looked into the official BMW spare wheel kit but was put off with the £340-ish asking price. Ended up doing my 'own' kit for less than £100. Sourced a 17-inch space saver spare (to ensure front brake clearance), wrench and jack from eBay, and then a mountain bike wheel bag to put it in. Sits in the boot and feel better knowing it's there. Been stung a few times in the past quite a distance from home with a flat. As it's a space saver doesn't take up too much boot either.
Hi Only1mike, have you tried fitting that spacesaver yet? Have you used the same bolts?
I just wonder because if the steel spacesaver is thinner than the alloys around the bolt-holes, the bolts will screw in further before they are tight. In this circumstance could the bolts interfere with something such as the handbrake in the rear?
I just wonder because if the steel spacesaver is thinner than the alloys around the bolt-holes, the bolts will screw in further before they are tight. In this circumstance could the bolts interfere with something such as the handbrake in the rear?
CarsOrBikes said:
you'll end up with tyre pressure warnings or traction control errors if altering the rear only, there'll be a diameter mismatch, and a rotation count error over several miles. Only my2p.
That should not happen if you do the initialising procedure after fitting. You're supposed to do it every time you re-set the tyre pressures anyway.CarsOrBikes said:
you'll end up with tyre pressure warnings or traction control errors if altering the rear only, there'll be a diameter mismatch, and a rotation count error over several miles. Only my2p.
You shouldn't have any of those issues so long as you stick to the recommended sizes and have them inflated to the recommended pressures - that is why the Space-savers have that profile in the first place! 
I went up 10mm in both fronts and rears, so haven't had any warning lights or other adverse affects. Well I say that, for the first 4 days I was getting Tyre Pressure warning lights, but that was mostly because ATS hadn't seated the front right tyre properly. Wish I'd known that before I jumped on the M6 to go to work, but hey ho. The effects I have noticed though:
- Ride is night and day better
- Traction is vastly improved
- Speedo is now accurate
- I don't have to avoid speed bumps any more
Only slight adverse effect I have noticed is MPG has dropped from just over 30 to 28, however that happened this time last year, so I am unsure if it is the tyres, or a temperature/winter fuel issue.
It's also had the additional effect that I am no longer thinking about the next car - the ride was getting pretty unbearable at times, and doing 20k a year it was less than ideal, but with the PS4's, it is absolutely fine.
- Ride is night and day better
- Traction is vastly improved
- Speedo is now accurate
- I don't have to avoid speed bumps any more
Only slight adverse effect I have noticed is MPG has dropped from just over 30 to 28, however that happened this time last year, so I am unsure if it is the tyres, or a temperature/winter fuel issue.
It's also had the additional effect that I am no longer thinking about the next car - the ride was getting pretty unbearable at times, and doing 20k a year it was less than ideal, but with the PS4's, it is absolutely fine.
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