|
|
|
|
|
|
BMW Garage | BMW Meets | Register | Today's Posts | Search |
|
BMW 3-Series (E90 E92) Forum
>
Tyre pressures - not as you would expect!
|
|
10-20-2011, 06:39 AM | #1 |
Private First Class
23
Rep 173
Posts |
Tyre pressures - not as you would expect!
My post LCI E90 330d SE runs on Bridgestone 225 45 R17 91W Run flats. Same tyres front and rear. Maybe its me, but the pressure plate on the car tells me pressures should be 2.5 bar front, 3.0 bar rear.
On all previous cars, the pressure was always greater for the front tyres than the rear, presumably to take into account the extra weight of the engine. So why are the rears on mine greater than the front? |
10-20-2011, 06:54 AM | #2 |
Major General
268
Rep 9,915
Posts
Drives: VW T5
Join Date: Apr 2008
Location: Worcestershire
|
RWD
__________________
|
Appreciate
0
|
10-20-2011, 07:07 AM | #3 |
Private First Class
23
Rep 173
Posts |
Simply that, RWD? But you can see my logic.....extra weight at the front seems to dictate a firmer pressure. I just checked by tyre pressures (my car is a recent second-hand purchase) and the pressures were about 30psi all round perhaps this is why the rears seem to have worn a little more than I expected. rears down to about 3mm tread, with 10k miles.
Off to inflate them! |
Appreciate
0
|
10-20-2011, 07:18 AM | #4 |
Major General
268
Rep 9,915
Posts
Drives: VW T5
Join Date: Apr 2008
Location: Worcestershire
|
50/50 weight distribution on the BMW.
__________________
|
Appreciate
0
|
10-20-2011, 07:52 AM | #5 |
Major
105
Rep 1,235
Posts |
In all my previous BMW's, I've always adjusted the tyre pressures in accordance to personal preference but ensured that its still fairly close to BMW's recommended ones. I've never got on with the recommended ones - my E92 felt rather dangerous to drive with the pressures at the recommended door jam ones. Took 0.1/0.2 bar off and it feels nice - even on the Bridgestone runflats. Been running them like this for a while now and tyre wear is also more even
|
Appreciate
0
|
10-20-2011, 08:11 AM | #6 |
Private First Class
23
Rep 173
Posts |
Now, having re-energised my tyres, im getting conflicting information - between the petrol stations air machine, and my trusty hand held pressure gauge! Which is more likely to be accurate? I was thinking of buying a digital gauge to replace my analogue one - anyone had experience of this type??
|
Appreciate
0
|
10-20-2011, 08:32 AM | #7 |
Major General
1394
Rep 8,081
Posts |
A piston-type hand held is what you need.
__________________
Ian
Current: 2021 G21 330i M-Sport Previous: 2018 A6 Avant S-Line MMI+, 2014 F31 320d M-Sport, 2013 F10 520d M-Sport, 2011 F10 530d M-Sport, 2008 320i M-Sport Coupe, 2002 325i, 2001 318i valvetronic, 1998 318i, 1996 525i, 1990 Porsche 944S2 |
Appreciate
0
|
10-20-2011, 08:38 AM | #8 | |
Brigadier General
224
Rep 3,016
Posts |
Quote:
|
|
Appreciate
0
|
10-20-2011, 08:47 AM | #9 |
Major
105
Rep 1,235
Posts |
I just use my local new-ish petrol station that has a paid for machine - meaning less people use it as there is a freebie a couple of roads down lol
I then check it against my digital tyre pressure gauge to confirm it - simples! |
Appreciate
0
|
10-20-2011, 09:22 AM | #10 | |
Colonel
54
Rep 2,197
Posts |
Quote:
Welcome to the club of people who don't like paying £3000 for a body kit and an explosion of fabric as grey as a British winter! |
|
Appreciate
0
|
10-20-2011, 10:09 AM | #11 | ||
Lieutenant General
3528
Rep 11,291
Posts |
Quote:
Quote:
You get badges too. |
||
Appreciate
0
|
10-20-2011, 10:11 AM | #12 |
Major General
1394
Rep 8,081
Posts |
Look out, he'll be back if you're not careful.
__________________
Ian
Current: 2021 G21 330i M-Sport Previous: 2018 A6 Avant S-Line MMI+, 2014 F31 320d M-Sport, 2013 F10 520d M-Sport, 2011 F10 530d M-Sport, 2008 320i M-Sport Coupe, 2002 325i, 2001 318i valvetronic, 1998 318i, 1996 525i, 1990 Porsche 944S2 |
Appreciate
0
|
10-20-2011, 10:36 AM | #13 | |
Private First Class
23
Rep 173
Posts |
Quote:
Oh and the economy too.... Having my cake AND eating it!! |
|
Appreciate
0
|
10-20-2011, 10:39 AM | #14 | |
Private First Class
23
Rep 173
Posts |
Quote:
|
|
Appreciate
0
|
10-20-2011, 11:45 AM | #15 |
First Lieutenant
21
Rep 373
Posts |
I have about eight different gauges including a Michelin digital, my favorite is a Race-x analogue which I suspect is a little more accurate, certainly it is nice use, bought mine off Amazon. I think it is very important to check pressures. The handling was out when I recently bought my approved used BMW (brand new Michelin RFTs)... turns out pressures were variably out by up to seven psi! Assume nothing when buying from even main dealers. Even 1-2psi difference can make significant handling differences, particularly at speed. That's why I check pressures at least once a month, the ambient temperature is worth noting too.
|
Appreciate
0
|
10-20-2011, 01:57 PM | #17 |
Private First Class
23
Rep 173
Posts |
|
Appreciate
0
|
Bookmarks |
|
|