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Hi There,

has any one pumped thier tires with helium gas? Did it make a difference in the bikes overall weight? How long did your tires stay pumped up?

Im curious coz here in Australia, many motor vehicles have their tires pumped up with helium to decrease their weight and save on fuel costs?

Cheers,
 

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I read through all of those links and this is the coolest thing I found:

"I've been talking to a guy in the research department of Nokian tires of Finnland, and he tells me, off the record, that they are experimenting with a new "rubber-type" compound that is essentially clear.....
They've been filling them with Neon gas and have found that the simple static electricity that is produced from rolling on trails or pavement produces enough power to make the wheels light up with a substantial glow...

Thus the product may soon be available for night riding.....for safety reasons it may become very popular. Glowing tires.... They tried it for auto tires but the casing is too thick to let the light through..

So glowing Neon tires are the next big development you'll be seeing....
And they roll real fast also like all Nokian tires..."
 

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Weird huh?
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Helium? soooo old skool

Hydrogen !!! son, Hydrogen !!!!

Lighter than helium. Oz needs to catch up with the 21st century.

Cheers
 

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PLURPIMPIN said:
lol then your bike ends up like the hindenburg
I would think that all these gases would tend to leak more under pressure. The neon sounds interesting, but I'd have to see it to believe it.
 

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not entirely true....

Yes some of the lighter gases would tend to leak obviously. I've had pretty good luck with some aftermarket sealants.

Stanzs Sealant is one of the better ones for helium. The do however warn against the use of either hydrogen or neon. Both of those gases leak appreciably faster. Stanzs warns that using either would void the warranty of their product.

That said, I know Jonny V Hempledirnt in Germany won the mens downhill using hydrogen in the front, and helium in the rear tires. Don't know if he was going tubeless, so I can't comment on if the Stanz woulda worked or not.

Cheers
 

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I just ran some rough numbers, and filling a 2.2" tire to 35 psi with helium instead of air would save about 12 grams per tire.
 

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cool

@dams gonna get just a little high..............

"don't forget to bring a towel"
 

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The better way to reduce the weight of the bike is to deflate the tires. Bonus: no gas in the tires means less rotating mass and hence a faster acceleration!

That is the main reason DH champs run their tires with low pressure.
 

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The better way to reduce the weight of the bike is to deflate the tires. Bonus: no gas in the tires means less rotating mass and hence a faster acceleration!

That is the main reason DH champs run their tires with low pressure.
.... :rolleyes:
 

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I'd say that if you put hellium into a bike tire you may explode in any minute put hydrogen that may work.
It's what they put into racing cars with nos so they don't flaten in any time. ;)
 

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All right let me put on my super-dork cap to respond to this one.

With Helium you will leak at a much higher rate than with any other gas. This is because it is a very small molecule and in gaseous form it is elemental (stands alone) and will fit through the smallest of pores. Hydrogen on the other hand has more lifting power than Helium and in gaseous form is found as H2 (has to team up with another Hydrogen molecule in order to be stable) so it is easier to seal up for Hydrogen. There is a little bit of worry because of the earlier post about static electricity in your tires, but remember in order to have combustion you have to have fuel and oxygen, so if the tire is filled entirely with Hydrogen there is no oxygen in there with it and it would be safe, but if you were leaking to the atmosphere and a spark happened you could have a nice flame shooting out of your tire, though Hydrogen fires tend to be invisible so you wouldn't see it (moral here, if your Hydrogen filled tire loses some pressure don't top it off with regular air as this would create an explosive environment in your tires). I'm in the aerospace industry and we do all of our leak testing of our components with helium because it will find the smallest of leaks. I've even seen helium leak through the wall of titanium tubing.
Some quick numbers:
Air is 3% heavier than Nitrogen
Air is 43% heavier than Neon
Air is 724% heavier than Helium
Air is 1440% heavier than Hydrogen
 

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mtbgiovanny said:
I'd say that if you put hellium into a bike tire you may explode in any minute put hydrogen that may work.
It's what they put into racing cars with nos so they don't flaten in any time. ;)
???

The tires on most race cars are filled with *nitrogen* primarily because nitrogen doesn't expand as much as compressed air when it heats up. As compressed air heats up the pressure goes up and the size of the tire grows changing the handling of the car. Nitrogen will expand but it's more predictable and controllable.
 

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HJB said:
???

The tires on most race cars are filled with *nitrogen* primarily because nitrogen doesn't expand as much as compressed air when it heats up. As compressed air heats up the pressure goes up and the size of the tire grows changing the handling of the car. Nitrogen will expand but it's more predictable and controllable.
And how much %nitrogen is in the atmosphere?

All gases expand with heat. There are fewer impurities when running nitrogen only gas (moisture aka water vapor) in tires when compared to air sourced from the atmosphere that may contain moisture and oils if used from an air compressor.

Interesting idea to run hydrogen in the tires though.
 

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Kaba Klaus said:
The better way to reduce the weight of the bike is to deflate the tires. Bonus: no gas in the tires means less rotating mass and hence a faster acceleration!

That is the main reason DH champs run their tires with low pressure.
I think that you should open up your physics/chemistry 101 book again!
Deflating your tires and going fast has nothing to do with the "weight" of the air in your tires. This weight is so miniscule that you physically could not notice the difference in weight. The reason for airing down the tires is for traction and to help the suspension.
 
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