Tire failure of S03 at 80 mph, Bad Valve stem?

[Emission]

I have some new street tires for my 930 (Yokohama AVS Sports) that are getting installed today.

As a result of this thread, I just called my tire installer. He doesn't have metal valve stems in stock. However, he suggested I go to NAPA and pick up a set and he would gladly install them when he mounts the tires.

I'll run over to NAPA before I drop the wheels/tires off at the installer...

[randywebb]

a black rubber/plastic cap weighs 0.4 g

2 reason not to just say 'BS"
1. maybe it isn't -- you 'd have to do the math and calculate the force at the tire rpm involved
2. there is too much opinion and not enough data on this bbs as it is...


BTW, a close friend of mine got a GED - she is now an attroney in DC...

[chibone_914]

Guys! never run a metal valve stem (it's actually nickel-washed brass or pot-metal) I have seen these things shear off at the track when debris hits the valve laterally. Just use the rubber valve stem with the stem support and you'll do fine. Oh yeah, just change the stems every season so you will decrease your chances of having the rubber stems fail due to drying out and shrinkage.

Oh yeah, most shops do not know how to properly install a metal valve stem anyway and end up pinching one or both of the small rubber seals on it, creating your leak again. Plus these seals are more susceptible to drying out and shrinking/cracking due to the heat cycling the wheel goes through. Rubber stems have, well a big, fat rubber base that is far more resistant.

[Emission]

Originally posted by chibone_914
"Guys! never run a metal valve stem.... Rubber stems have, well a big, fat rubber base that is far more resistant."

Damned if you do, damned if you don't....

I do high speed more often than get hit by debris strong enough to take out my valve stem (the ones I just bought are plated brass). Calculated risk for me.

[deltajetfixer]

Looks a LOT "cleaner" than my tire failure at 80...

[Emission]

deltajetfixer - Yikes!

Anyone subscribed to this thread using tire pressure monitoring systems?

[Bill Verburg]

Originally posted by chibone_914
Guys! never run a metal valve stem (

BS!

[randywebb]

Exactly. Think about it -- a high speed piece of shrapnel hits the metal stem with enough force that it shears it off... Now what would that do to a rubber stem? Eh? If you don't think it would cut thru the rubber, tell us why.

[Formerly Steve Wilkinson]

Why do these people who post messages like the idiotic one about metal stems being potmetal that are usually misinstalled think we 1/buy potmetal stems and 2/have our tires mounted by morons?

(Actually, I now see that the poster styles himself "Village Idiot." Make it "mounted by idiots.")

Stephan

[Bill Verburg]

Why do these people who post messages like the idiotic one about ....

They're everywhere

[no substitute]

My valve stem of choice is the Irving Mainway hand cut crystal valve stem.

[Emission]

Originally posted by no substitute
My valve stem of choice is the Irving Mainway hand cut crystal valve stem.

Nice, but I've heard if the light hits them just right, the sunlight will burn a hole in your sidewall.

[efhughes3]

Originally posted by Formerly Steve Wilkinson
I use metal valve stems. The rubber-stem supports are cute, but the sticky-tape glue quickly melts on the track wehn the wheels get hot.

Stephan

I lost a stem at TMS at speed a year or so ago, ended up trashing the tire (S03). I put the supports on, and have driven in several DE's since, and Texas heat with no problems with the adhesive...

[89911]

My Fikse's have nice metal valves. I guess no one made them aware of the "flying debri", phenomena. I did have heavier stem Porsche crests on these which may of contributed. But I never ran these much higher then 75 mph. It could all be down to one defective valve stem setting off a whole conspiracy.

[Formerly Steve Wilkinson]

Aw,shoot, that there Texas heat is nothin' like yer Noo Yawk heat...

Stephan

[efhughes3]

Originally posted by Formerly Steve Wilkinson
Aw,shoot, that there Texas heat is nothin' like yer Noo Yawk heat...

Stephan

It's a well know fact that 105 degrees in TX has a much higher caloric and BTU content than 105 in NY

[NoLift911]

Originally posted by chibone_914
Guys! never run a metal valve stem (it's actually nickel-washed brass or pot-metal) I have seen these things shear off at the track when debris hits the valve laterally. Just use the rubber valve stem with the stem support and you'll do fine. Oh yeah, just change the stems every season so you will decrease your chances of having the rubber stems fail due to drying out and shrinkage.

Oh yeah, most shops do not know how to properly install a metal valve stem anyway and end up pinching one or both of the small rubber seals on it, creating your leak again. Plus these seals are more susceptible to drying out and shrinking/cracking due to the heat cycling the wheel goes through. Rubber stems have, well a big, fat rubber base that is far more resistant.

Dude - Ever get out to the track much?? You know the guys that race for a living and millions of dollars in prize money with life and limb at stake?

Ever see rubber valve stems on any of those cars? (The answer is no btw)

You need to leave the village and get out a bit...

-Jeff

[MovOvr1]

I actually run with the a rubber stem, long aluminum valve stem caps for support and the original valve stem supports. I haven't had a problem but like the looks of the metal stems better.

Brian

[randywebb]

Let's not attack that guy too much -- he was just trying to be helpful.

{That doesn't mean we should all substitute opinion for data, analysis or opinion tho....}

[Formerly Steve Wilkinson]

Good point.

Stephan