NITROUS OXIDE ( nos / n2o ) advice forum

righty ho, I've just been outside and weighed my full, un-touched NOS bottle, it's a 5lb bottle and full it weighs 8lbs exactly so that must mean that when full a 5lb bottle holds approximatley 3lb's of Nitrous oxide. so going by that, half full will be approx. 6.5lbs and when its empty its going to weigh near on 5lbs again.

Hopefully this is some use to someone else too????!!!

To find the amount of nitrous left you weigh the bottle and then subtract the Tare, you will find the tare figure stamped on the bottle, this will give you the nitrous left in the bottle.

My 5lb bottle weighs 13.35lbs when full so 8.35 empty

Back to school young drumer.

A 5lb bottle holds 5lb of Nitrous liquid/gas.

The Tare is minus the vavle weight.

Sounds like youve bought 3 LBS of air.

My bottle with high-flo valve and bracket is -

5.46KG full - 2.25KG of NO2 = 3.21KG empty.

Hi,
Just to clarify, a 5lb bottle won't actually hold 5lb's of nitrous (sounds crazy I know). It's in fact a 2 kg bottle which is just about 4.5 lbs of nitrous. However, it's pretty easy to squeeze in that extra 1/2 lb.

Now the empty weights of bottles tend to vary (the Tare weight on the side doesn't include the valve) as valves vary, some people have QR brackets mounted, some have gauges etc. A standard current 5lb bottle and valve empty weighs 2.765 kgs, officially it should weight exactly 4.765 kgs when full, although it's not difficult to squeeze in that etc .25 kgs it may cause your bottle pressure to climb dramatically so be aware!

Our bottle labels have provision for the exact tare and gross weights, so the best thing to do is write the empty weight in of whatever combination of components you add to your bottle for the tare weight and then add recommended nitrous content for the gross weight.

Regards

Ok, so going by that, and my calculations, which aren't strong at the best of times (thank god my fiance is an accountant), a full bottle should weigh 10.494lbs including the valve??? and 6.09lbs including the valve when empty??

So, weighing my bottle, i can now say that the full weight of the bottle was 8lbs exactly and using the empty figure above of 6.09lbs then according to my calculations I have 1.91lbs of liquid in the bottle!! so the 5lb bottle holds 4.5lbs of liquid so that must mean that the bottle is missing approximately 2.59lbs!! So its approx half full!!

Am I correct????

God my brain hurts

I had my 11lb bottle filled this weekend, I weighed it empty before it took it and when i got home and re-weighed it was only 5.5lbs heavier. surely this isnt right?

Colosus,

Your method (assuming you're using accurate scales) is the right way to determine your empty and full weights.

The full weight is your empty weight plus that of the gas.

A 2 Kg bottle (5 lb for those who don't do metric or fractions) should weigh 2 Kg more that the empty weight when filled and likewise the 5 Kg bottle should weigh in at 5 Kg more than the empty weight.

I've said this before but the thread has got lost in the mists of time so it seems it's time for a repeat.

Buy yourselves a set of fishing scales with a suitable range before going to a company for a fill.

Show them the weight on YOUR scales before you hand over your bottle.

As soon as you are given back your bottle and before you part with your cash, show them the weight on YOUR scales again.
If the difference is less than the weight that SHOULD be in the bottle, only pay for the difference between the empty weight and the returned weight.

By showing them you know your before and after weights you are less likely to be ripped off.

Regards

Exactly Trevor!! thats why i'm trying to clarify in lamens terms how to weigh it and the correct weights and the formula for doing it. so far, all my weights have been done on a fishing scale that goes up to 50lbs. BTW, been meaning to mention that I enjoyed the top gear piece that you did with the Jag, very impressive performance you managed to squeeze from the car. how did the 200 shot effect the engine in the end, i heard that it eventually let go???? is that correct???

Toby forget the formulas etc., just weigh the bottle when it's empty and then add the contents weight for the full weight - it's that simple!

Any other way is going to be inaccurate because there are a number of extra components that could be added to the bare bottle.

Alternatively give us a call and tell us exactly what you have and we'll get the weight by weighing the same combination here.

Thanks for your comments about the Top Gear Jag piece.

Contrary to what you've been told the Jag did NOT suffer any engine problems from using the nitrous. The engine itself could have handle at least double that amount but the ignition and gearbox couldn't, as they both started to fail when we tried 250 hp.
Consequently we had to settle for the results of the 200 hp run which I was very disappointed about, as I was looking forward to beating the Stig by a much bigger margin.

If you'd like a copy of that and one of the 5th Gear piece we did, we're giving away a free CD with each copy of my book.

www.noswizard.com

Regards

Can someone make this thread a sticky please.

Regards

It's the same principle as for filling your camping gas (LPG, propane or butane) bottle or any liquified gas. Watch out for uneducated race shops. The risk part from getting less is to get too much and then losing it all when the bursting disk blows unless you have a WON bottle with the relief valve.

should you be able to feel or hear the nitrous sloshing about in the bottle if you shake it ,only im sure mine should still be pretty full cause its not been used much and is only running small jets,but it feels like theres nothing in it

If you had liquid you should be able to feel it "slosh about" but your best way is to weigh it.

Regards

Hello, when you "if you had LIQUID" does that mean the nitrous can come in gas or liquid form when your bottle gets filled?

Reason i ask is that i've just ordered one of your kits earlier today and i've been phoning around to find out how much to get refills and i want to be 100% on all the aspects of refilling before getting it done as i don't wanna get fisted on the price! A place near me wanted £60 to refill the 11lb bottle i'm getting (£5.50 per lb) but i was thinking that that doesn't sound right as the empty bottle should weigh approx 3 - 4 lbs going by what i'v read then another 7lbs approx of n2o to go in so should cost approx £40.

There are a number of prior threads that deal with this in detail, using the search feature should turn one of them up for you.
You'll also find full details of everything you could ever want to know in my book.

However for a brief response I can tell you;
1) Yes you can get shafted so buy yourself some fishing scales, so you can check the empty (before weight) with the full (after fill weight) to make sure you ONLY pay for what you get.
2) Yes you could end up with gas rather than liquid in the bottle and this would be useless.
3) The weight of 11lbs means the weight of nitrous liquid it contains when full - it does not include the weight of the bottle - the gross weight figure stamped in the neck of the bottle gives you the toatl weight of a full bottle.

Regards

Ok cheers, i do have your book but can't remember the last person i let burrow it lol!

Thanks for your help!

Big mistake lending out the book, it should be by your side till you're too old to need it.

Regards

Not to sidetrack the discussion, but there are reasonably accurate, inexpensive, digital "postage scales" available on e(vil)bay (and other online sources, I'm sure). I have one that measures from 0-50lbs total weight, and it cost me a whopping $40.00 USD incl. shipping. It is much easier to use than the "fish scales" that I've seen some people using in the pits...

...carry on

I've weighed my bottles on my charging scales when empty. And written the MT weight on the bottles with a magic marker as I can never remember what it is.
I dont get any problems now when topping up.

11lbs bottle with QR-bracket, SPRV and D4 adapter.

empty: 6,92 kg
N20: 5,0 kg
full: 11,92 kg

just for info and to remind

i've had a bit of a problem with filling a large 11lb bottle. It's a nice shiny new luxfer, pie marked bottle. had been leak tested with compressed air to about 150 psi, not ideal but apart from filling how else can you check?
Any way i took it to shakey to get filled by ............(i'm sure you know who i'm on about they only do NOS) who are there at most meetings they had a grumble about the bottle type and the highpower fittings but after some messing about managed to get just 5lb in. told me that luxfer type bottle meant for co2 so possibly will not hold the 11lbs that you might think it should. only had to pay for 5lb so no real harm done.
So rather than keep all my eggs in 1 basket so to speak i immediately went back to the van and filled my 2 small (20oz & 16oz) bottles all went well.
having done a bit of messing around and the static testing the 20oz was low so thought a top would be a good idea, bottle in freezer over night, hooked up to filler sat on scales -bit of a hiss..... then nothing! no weight gain nothing! all thats left in 11lb bottle is gas!
what have i done wrong? the 11lb bottle has dip tube.. by my reckoning i should have had 40oz + left!
I'd like to make sure i'm not doing anything stupid before i refill ... hopefully at one of the agents listed on this site one in solihull would be great i'll bell them shortly to see if they're still going otherwise off to streetcar in warwick.