I was changing some tyres last night and as I was pumping them up with air, I suddenly thought that if I were to use Helium in stead of air, then surely it would make my bike much lighter?
Think it's been tried by MBUK back in the noughties and it just pissed through the pores in the tube.
you need to fill them with shit - everybody says so whenever we talk about light bikes
(even just trumping in there might work, and be easier to work with)
Just remove the innertube and screw the valve directly into your rim! Ta Daaa
you could try drilling out some of the excess material from the components. Like the cranks and stem 😀
Even if you could do it properly, I think you'd save less than a couple of mouthfuls of water. My back of a cig packet calculations says 20-30g probably.
Someone told me Eddy Merckx had helium in his tyres back in the day. Based on the MBUK comment above it seems this may be lies.
Shave your BB shell from 73mm to 68mm.
use a really small frame, short stem and narrow bars?
no suspension?
20inch wheels?
wont work my kids bikes are heavier than mine 😉
Helium in your tyres? Amateur. Hydrogen is far lighter.
Jeeze you lot, you're all overlooking the simplest solution 🙄
Just ride with loads of helium filled ballons tied to your bike 😀
You can't get lighter than a vacuum. Although tyres strong enough to support themselves may be a little heavier...
Helium in your tyres? Amateur. Hydrogen is far lighter.
But just a tad more flammable.
But just a tad more flammable.
Why's that a problem when it's safely confined inside your tyres?
I watch mythbuster regularly and it made **** all difference in a small volume item like an inner tube.
Why's that a problem when it's safely confined inside your tyres?
It was safely inside the hindenburg.
Then fill all of the hollow parts (bars, stem, seatpost, frame, tyres, rim cavity) and a helium filled carbon fork and it could potentially. There may need to be some kind of helium piggyback on the frame for maximum gas storage, or a rope tied to the basket of a hot air balloon...
It was safely inside the hindenburg.
**imagines awesome rock/tyre interface followed by massive explosion**
F1 use nitrogen don't they? Is there any mileage in that, or is it just because it's more 'consistent'?
You could buy one of the S-works carbon bottle cages for fifty quid; then put a 1lb bottle of water in it.
I suppose you could put helium in the frame at really high pressures, so you get more lightness in there
Possibly a slow release valve at the back for low-grade jet propulsion too
F1 use nitrogen don't they? Is there any mileage in that, or is it just because it's more 'consistent'?
Instead of air to make your bike lighter? You do know what the main constituent of air is don't you?
"F1 use nitrogen don't they? Is there any mileage in that, or is it just because it's more 'consistent'?"
Apparently its not as sensitive to temperature change therefore doesnt change the pressure in the tyre as much.
Indeed I do, but I wasn't totally sure why they use pure nitrogen, just recall it was related to stability.
How much would it cost? Isn't helium pretty expensive since we're running out?
njee20 - Member
Indeed I do, but I wasn't totally sure why they use pure nitrogen, just recall it was related to stability.
Yeah, it doesn't expand & contract as much as regular air.
"How much would it cost? Isn't helium pretty expensive since we're running out?"
Thats not a problem for most STW people though is it, they will spend a fortune on other components to save weight, so why not on a gas?
Holy crap, you're a genius! You'll make millions!
How come noone's ever thought of this before?!
Alternatively just have a shave and a dump before you go for a ride....
[sarcasm]I suppose you could put helium in the frame at really high pressures, so you get more lightness in there[/sarcasm]
FTFY
It was safely inside the hindenburg.
Right up to the point it wasn't.
Please desist from your Helium based get rich quick scheme and consider the implications of your actions.
Helium is a non-renewable resource produced either by the nuclear fusion process of the Sun, or by the slow and steady radioactive decay of terrestrial rock, which accounts for all of the Earth's store of the gas. There is no way of manufacturing it artificially , and practically all of the world's reserves have been derived as a by-product from the extraction of natural gas. Due to its lightness once released it is capable of escaping the earths atmosphere. Once its gone its gone.
It is used to super-cool the electronics that generate the magnetic fields required for MRI scanners, NMR instruments & Fourier Transform-Ion Cyclotron Resonance Mass Spectrometers - which are used for all sorts of medical and scientific research applications.
I am surprised it is still allowed to be used for party ballons...
I don't get invited to many parties!
On a serious note does a compressed gas weigh less because there is more of it?
What I’m saying is...if you put a lot of gas under pressure into a vessel does it get proportionally lighter the more volume (higher pressure) you put in?
If so those Bottles of balloon gas, do they get heavier the more you draw-off.
Im all confuwsed nowe
On a serious note does a compressed gas weigh less because there is more of it?
What I’m saying is...if you put a lot of gas under pressure into a vessel does it get proportionally get ter the more volume (higher pressure) you put in?If so those Bottles of balloon gas, do they get heavier the more you draw-off.
Im all confuwsed nowe
1 mole of gas (a fixed number of molecules, equivalent to the number of molecules in 12grams of carbon12) will occupy a known volume at a known temperature and pressure according tot he following equation known as the ideal gas law (it's called ideal because it only works on ideal gases, of which there are precicely none, but it's pretty much accurate most of the time, basicly it doesnt account for the intra molecular forces pullign molecules together or the fact that you can't compress them entirely as the molecules take up some space).
PV=nRT
P= pressure
V=volume
n= number of moles
R= ideal gas constant
T= temperature
So if you double the pressure then you have to have double the number of moles thus double the weight, tyres run at about 2 bar (guage, i.e. relative to the atmosphere), atmosphere is about 1 bar, so the air in your tyre is 3x heavier than the air outside.
However 1 mole of helium weighs a lot less than 1 mole of 'air' as each molecule weighs a lot less. Thus to get the same pressure in the same volume at the same temperature you need the same moles, but less mass.
The problem is that smaller/lighter molecules can pass through the gaps between the rubber molecules in the innertube.
Alternatively you could heat your tyres upto 3x the temperature, to get a siilar effect but no ones figured out how to maintain tyres at 600degC.
So its no good for tyres.
Could fill my frame with gas?
It was safely inside the hindenburg.**imagines awesome rock/tyre interface followed by massive explosion**
wouldn't it be a sqeaky pop?
Could fill my frame with gas?
Yes, but it'd make less diffeerence as it's not compressed.
Why not fill your tyres with Nitrous Oxide for a laugh.
After careful study I have found that a combination of gasses in the following proportions works perfectly in tyres :
Nitrogen 78%
Oxygen 21%
Argon 1%
Plus trace amounts of other elements such as Neon, Helium, Krypton and Xenon
I am willing to supply this pre-mixed to STW readers at a bargain price (collection only)
What you need to do is ride near a gravitational anomaly or at high altitude. Your bike is 0.28% lighter at the top of Everest compared to sea level, thats 42g on a 15kg bike....and free!
Alternatively, and for significant gains, you could head off to the moon for a weekend of dusty trails.