Tirerack
Use the following links to go directly to useful tirerack winter items: Tirerack Winter Tires. Gary's Winter Tire FAQ.
Using the links directly supports E90Post with tirerack sales commision!

  E90Post
 


TireRack

   PLEASE HELP SUPPORT E90POST BY DOING YOUR TIRERACK SHOPPING FROM THIS BANNER, THANKS!
 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > Wheels and Tires Forum Sponsored by The Tire Rack > New Tire - help



Wheels and Tires forum Sponsored by The Tire Rack
Please help to directly support e90post by doing your tirerack shopping from the above link. For every sale made through the link, e90post gets sponsor support to keep the site alive. Disclaimer

Wheel offset calculator courtesy of BimmerPost.com. You may use this calculator to calculate what tire sizes you might need if you upgrade your tires, or what wheel sizes/offsets are compatible with your car.
    Current Wheel Width  inches             Current Wheel Offset  mm.
         New Wheel Width  inches                  New Wheel Offset  mm.
 
TIRE WIDTH
/
ASPECT RATIO
- WHEEL DIAMETER
ORIGINAL TIRES
/
NEW TIRES
/
Based on your stock wheel setup, your new wheel will have:
Original Tires Diameter (in.)
      New Tires Diameter (in.)
  Difference in diameter (in.)
           Percent Difference %
                     
Speedo @60mph will read: mph
Collapse/Expand the BimmerPost Wheel and Tire calculator
Reply
 
Thread Tools Search this Thread
      04-20-2013, 12:59 PM   #1
BlueBimmer
Enthusiast
 
BlueBimmer's Avatar
 
Drives: 2009 335i Convertible
Join Date: Apr 2012
Location: PA

Posts: 272
iTrader: (5)

New Tire - help

Last week - I finally bought a set of super sports
They are amazing, got them from tire rack and they arrived the next day!!

Anyway they were installed on Thursday on the stock 189s. These are my "good" rims as the other 19s seem to attract potholes and tend to crack.

So installed on Thursday, had them road force balanced and also did an alignment. I picked up the car, checked all the PSIs myself with my gauge to make sure they are accurate (35front, 42 rear) and drove home.
Friday I drive to work and back and then go out at night - so far I put about 60 miles on the tires. At night I go out and on my way home the TPMS light turns on, it is raining really bad so I check to see if it's a flat which it isn't then I go home - this morning I check all 4 tire pressures. The one that had the TPMS light was down to 30 PSI (driver rear), the fronts were too too - 33 instead of 35 and the other rear was 40 instead of 42.

Is this a tire problem, installation problem or what?? The driver rear was 12 PSI lower than when I took the car 36 hours earlier? THe fronts may have been temperature related - any thoughts, I filled them back up this morning and they seem to be holding so far ....

My installer was a very reputable shop - rated 5 stars everywhere including tire rack, yelp ...
BlueBimmer is offline   United_States
0
Reply With Quote
      04-20-2013, 06:33 PM   #2
Hybrid For Life
Banned
 
Drives: Out of Spec
Join Date: Nov 2011
Location: Santa Barbara, CA

Posts: 2,119
iTrader: (4)

any chance the compressed air that was used to inflate your tires was fresh out of the compressor? Air expands when heated and increases in pressure, when you compress air (with an air compressor) the air is naturally heated thus increasing its pressure.

My best guess is the compressor was either running or had just cycled at the tire shop witch allowed "hot" air into your tires when they inflated your tires. At night when the outside air temp drops a bunch so does the temp of the air in your tires, causing your psi to drop compared to the psi when they were inflated.

Lets say the air the tire place filled your tires up with was 130 degrees and night it could easily be 40 degrees.
Hybrid For Life is offline   Germany
0
Reply With Quote
      04-21-2013, 09:49 AM   #3
BlueBimmer
Enthusiast
 
BlueBimmer's Avatar
 
Drives: 2009 335i Convertible
Join Date: Apr 2012
Location: PA

Posts: 272
iTrader: (5)

Quote:
Originally Posted by Hybrid For Life View Post
any chance the compressed air that was used to inflate your tires was fresh out of the compressor? Air expands when heated and increases in pressure, when you compress air (with an air compressor) the air is naturally heated thus increasing its pressure.

My best guess is the compressor was either running or had just cycled at the tire shop witch allowed "hot" air into your tires when they inflated your tires. At night when the outside air temp drops a bunch so does the temp of the air in your tires, causing your psi to drop compared to the psi when they were inflated.

Lets say the air the tire place filled your tires up with was 130 degrees and night it could easily be 40 degrees.
thanks for the input, I never knew this. so far the air I put in yesterday is still there. this morning - both rears were @ 41 PSI (colder day than yesterday), if it holds above 40 till tonight, this may be the culprit.
BlueBimmer is offline   United_States
0
Reply With Quote
      04-21-2013, 10:42 AM   #4
Casca
Captain
 
Drives: E90 6MT
Join Date: May 2010
Location: California

Posts: 630
iTrader: (0)

Maybe the Schrader valve core is not screwed down as tight as needed. Go back and have them check/re-tighten them all or buy your own schrader valve tool for less than $10 and check yourself.

Try taking the valve stem cap off, get a flat piece of metal and put that level over the valve stem. If that presses the schrader valve and allows air out, it is not down far enough. I always put the schrader valve core down far enough to be just below the lip of the valve myself. Or get a spray bottle, mix it with a solution of water and liquid dish soap. Spray that on the valve stem and see if any bubbles form. Spray it around the bead of the tire, check for bubbles and so on.
Casca is offline  
0
Reply With Quote
      04-22-2013, 10:39 AM   #5
BlueBimmer
Enthusiast
 
BlueBimmer's Avatar
 
Drives: 2009 335i Convertible
Join Date: Apr 2012
Location: PA

Posts: 272
iTrader: (5)

Quote:
Originally Posted by Casca View Post
Maybe the Schrader valve core is not screwed down as tight as needed. Go back and have them check/re-tighten them all or buy your own schrader valve tool for less than $10 and check yourself.

Try taking the valve stem cap off, get a flat piece of metal and put that level over the valve stem. If that presses the schrader valve and allows air out, it is not down far enough. I always put the schrader valve core down far enough to be just below the lip of the valve myself. Or get a spray bottle, mix it with a solution of water and liquid dish soap. Spray that on the valve stem and see if any bubbles form. Spray it around the bead of the tire, check for bubbles and so on.
Thanks, I haven't seen any issues during the weekend - only that blip Friday night. I will stop by them today to see if it could've been this or the hot air issue/new compressor.
BlueBimmer is offline   United_States
0
Reply With Quote
      04-22-2013, 01:34 PM   #6
VMRWheels
BimmerPost Supporting Vendor

 
VMRWheels's Avatar
 
Drives: BMW
Join Date: Jun 2007
Location: Anaheim, CA

Posts: 13,475
iTrader: (4)

Garage List
2014 BMW F22  [0.00]
2013 BMW F06  [0.00]
2013 BMW F30  [0.00]
You definitely have a leak somewhere. Could be the valvestem area of your setup. I'd recommend spraying down the bead area of the tires on both front and back, along with the valvestem, to determine where your leak is coming from.
__________________

VMR | Wheels - Mitch A. | p. 714-442-7916 extension 107 | e. Mitch@velocitymotoring.com | ** VMR Winter Wheel/Tire Sale! **
VMRWheels is offline  
0
Reply With Quote
      04-23-2013, 07:01 PM   #7
Casca
Captain
 
Drives: E90 6MT
Join Date: May 2010
Location: California

Posts: 630
iTrader: (0)

Should also point out, sometimes the bead around a tire does leak a little when it is new and you can expect a little bit of pressure loss. After some driving, heat and braking, the rubber of the tire will move a little against the rim and form a better bead.
Casca is offline  
0
Reply With Quote
      04-24-2013, 01:29 PM   #8
BlueBimmer
Enthusiast
 
BlueBimmer's Avatar
 
Drives: 2009 335i Convertible
Join Date: Apr 2012
Location: PA

Posts: 272
iTrader: (5)

Quote:
Originally Posted by VMRWheels View Post
You definitely have a leak somewhere. Could be the valvestem area of your setup. I'd recommend spraying down the bead area of the tires on both front and back, along with the valvestem, to determine where your leak is coming from.
Quote:
Originally Posted by Casca View Post
Should also point out, sometimes the bead around a tire does leak a little when it is new and you can expect a little bit of pressure loss. After some driving, heat and braking, the rubber of the tire will move a little against the rim and form a better bead.
You guys are the bomb. You were absolutely right, this morning I found the pressure @ 35. I took it in and they found a very tiny leak between the rim and the tire, they cleaned it out and it should be fine- Thanks to all for the help, I am so glad it wasn't a tire or rim issue!!!

I also think the hot air was the reason of the very large PSI drop initially.
BlueBimmer is offline   United_States
0
Reply With Quote
      04-24-2013, 01:40 PM   #9
VMRWheels
BimmerPost Supporting Vendor

 
VMRWheels's Avatar
 
Drives: BMW
Join Date: Jun 2007
Location: Anaheim, CA

Posts: 13,475
iTrader: (4)

Garage List
2014 BMW F22  [0.00]
2013 BMW F06  [0.00]
2013 BMW F30  [0.00]
Yeah, sometimes a little piece of dirt won't allow the tire to seat properly. Glad you got that all sorted out though!

The same thing happened to me a few times.
__________________

VMR | Wheels - Mitch A. | p. 714-442-7916 extension 107 | e. Mitch@velocitymotoring.com | ** VMR Winter Wheel/Tire Sale! **
VMRWheels is offline  
0
Reply With Quote
Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 03:29 AM.




e90post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST