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Sheilz
4th March 2010, 11:35 PM
Last week Munro was driving Dougall when the runflat light came on. Tyre pressure was fixed and indicator reset, or so he thought. Today I took Dougall (first time have had him out since Jan) to the garage to check the tyre in question. Pressure at zero but no warning from the system. Munro's sure he reset it properly, certainly the light disappeared from the clock. Is it possible to only haf reset it?

Now have to wrestle with 2 x runflats or 4 x normal tyres. Am really tempted with the uniroyal sports 2 but am wondering if its ok to put these on just now since they're advertised as summer tyres. Also haven't got a spare tyre so if I decide to get these or any alternative anyone can recommend, is it best to get tyres with tyre weld added to them or to go with keeping gunk in the boot. Another question 215 45 17 W - is this an ok fitment for clubman? The regular fitment just seems so limited. Whenever I type it into the calculator on different websites it always comes up with runflats.

Stewart
5th March 2010, 12:32 AM
I’m sure Paul or Craig will be on they seem to know there tyre stuff.

As with the pressure warning as far as I know it does not check the actual pressure but only if there is a pressure change while driving to indicate something may be wrong all done with the rolling radius as it says in the book.

Could it be that the tyre has a puncture, the warning came on and the pressure was put right and the warning reset when the car got home (as you’d need the book) and on the drive for the car to sit on the drive. When you start the car the system needed to have the car moving to initialise the system and by that time it had gone flat again or not driven far enough. I know when they changed my Wheel ( and did not reset it) it did not come on for a good few miles as i was on the motorway heading home and had to drive a wee bit from Menzies to get on the m-way.

how close is the Garage?

Sheilz
5th March 2010, 12:53 AM
I’m sure Paul or Craig will be on they seem to know there tyre stuff.

As with the pressure warning as far as I know it does not check the actual pressure but only if there is a pressure change while driving to indicate something may be wrong all done with the rolling radius as it says in the book.

Could it be that the tyre has a puncture, the warning came on and the pressure was put right and the warning reset when the car got home (as you’d need the book) and on the drive for the car to sit on the drive. When you start the car the system needed to have the car moving to initialise the system and by that time it had gone flat again or not driven far enough. I know when they changed my Wheel ( and did not reset it) it did not come on for a good few miles as i was on the motorway heading home and had to drive a wee bit from Menzies to get on the m-way.

how close is the Garage?


This makes sense. It was the first time the light had come on so hadn't looked at how to reset it before hand. The car was driven about twenty miles before he reset it so I guess it could have been deflated by that time. Am counting the miles he's done in it since the indicator came on and am thinking the car will have to stay put till replacements are sorted. I suppose it will help me to be a bit more decisive about replacement tyres. Drat!

Craig
5th March 2010, 09:08 AM
The run flat indicator only deals with "sudden" drops in pressure. I have had a tyre with zero pressure in it before and no warning which was down to a faulty valve slowly letting the air out.

As for tyres I would always say go for STD tyres. I know you do a lot of miles so it would be cheaper for you also . Downside is not having a spare. Never used the gunk so can't comment. Also re "summer" tyres, what most people don't realise is that most tyres sold are branded as summer tyres but people use them all year round. I have done that for years, only this year having winter tyres. The rainsports are a great tyre but the equivilent falkens or khumo are just as good especially when you take into consideration your mileage ;). Hope this helps

Sheilz
5th March 2010, 11:59 AM
The run flat indicator only deals with "sudden" drops in pressure. I have had a tyre with zero pressure in it before and no warning which was down to a faulty valve slowly letting the air out.

As for tyres I would always say go for STD tyres. I know you do a lot of miles so it would be cheaper for you also . Downside is not having a spare. Never used the gunk so can't comment. Also re "summer" tyres, what most people don't realise is that most tyres sold are branded as summer tyres but people use them all year round. I have done that for years, only this year having winter tyres. The rainsports are a great tyre but the equivilent falkens or khumo are just as good especially when you take into consideration your mileage ;). Hope this helps


Yes it does. Thanks. Have bit the bullet and ordered four rainsports. Getting them fitted some time today. Four tyres for less than a hundred more than two runflats. In these straitened times it makes sense to go for the long term cheaper option. I've done just under 11000 on car since getting him in August which I suppose is still higher than average despite having very little miles put on these past seven weeks. Am looking forward to experiencing the better handling that I've heard other people talking about.

Sheilz
5th March 2010, 12:01 PM
PS Does this mean the runflat indicator is now null and void?

Stewart
5th March 2010, 12:32 PM
That a great question!
I'm sure you just disable it as it says in the book if you are on snow chains etc.

That reminds me its been months since I last got checked my pressure. should be at 2.2 Bar or 32 psi my tyres.

Craig
5th March 2010, 12:43 PM
The run flat indicator is not in the tyre (think it is a sensor in the hub). It's all to do with it detecting a wheel rotating at a different speed to the others due to being deflated. The RFI will still work (as it does on mine) but as usual they are tempremental so don't always believe it!. ;)

Delboy
5th March 2010, 03:48 PM
Sheilz - what size of tyre did you go for? Are they Uniroyal Rainsport? Will be interested to hear your feedback on how the car drives with them on. I'll be needing two runflats in the near future so might consider something similar.

N16SHP
5th March 2010, 04:43 PM
Where abouts are you getting your tyres fitted Sheilz?

Sheilz
5th March 2010, 06:26 PM
Got them fitted at Law's Tyres. Mark the manager is a friend of Darren's. I find the price and he matches them though I think he's pretty accommodating with all their customers. Have only driven the car home but did think it felt more responsive, perhaps a wee bit lighter. Still had 7mm tread on rear tyres so took them home. Also got some holts tyre weld just in case!

tyres are 215 40 17. Think Dougall needs some eibachs

KenL
5th March 2010, 09:33 PM
Last week Munro was driving Dougall when the runflat light came on. Tyre pressure was fixed and indicator reset, or so he thought. Today I took Dougall (first time have had him out since Jan) to the garage to check the tyre in question. Pressure at zero but no warning from the system. Munro's sure he reset it properly, certainly the light disappeared from the clock. Is it possible to only haf reset it?


If it had been reset properly after the tyre pressure had been corrected the system should have spotted it, but maybe only after driving for a certain amount of time.

I tested the system on my R56 Cooper, with 16" runflat tyres. I got all tyres to the same pressure, then took 5 psi put of one tyre and drove for a bit. Not noticed. I then took another 5 psi out, not noticed, another - not noticed. When I took another 5 psi out of the one tyre it noticed it after a mile or so. It had to be down 15 psi. These were runflats, normal tyres may show a loss of pressure earlier as their sidewalls give earlier leading to a change in differential rotational speed.

As Craig said, the system will only recognise a change in pressure in one tyre. If they all naturally go down to 15 psi or so over a year this will not be noticed as all wheels will still rotate at the same speed.

Stewart
5th March 2010, 10:08 PM
Checked my tyres today just to make sure, only down 3 psi each so back to 32 psi....think I'll go a buy one of those digital tread readers as the front are looking low although still well above the Tread indicator.

Sheilz
6th March 2010, 02:06 AM
Funny tonight while out testing out the new tyres I noticed my comp appears to have lost the facility of advising which gear i should be in. Not that I pay it any attention its realy just daft forever telling me to leap over roundabouts in 6th !

Stewart
6th March 2010, 02:11 AM
I think you can switch it off and on. I lost it and had to find out how to get it back as I quite like it, it reminds me there is a sixth.:blush: