OK, I'm a big fan of tubeless, but the one thing that still fucks me off after many years is the pain of inflating them.

I don't want to buy a big heavy and expensive air compressor (i.e. a small petrol engine bolted onto an air tank).  In my experience CO2 cartridges are almost enough to inflate a DH tyre, but when it doesn't work it gets expensive.

Now my track pump will pump up to 200psi quite happily, and those crappy £10 12v car tyre inflaters normally claim 250psi or so.  So what I'm after is a small air tank - a gallon at most, I think even a litre would do.  I want a connector on it that will let me inflate my bike tyres with presta valves from it, and a connector on it that will let me pressurise it from a track pump/12v pump.

Any smart ideas from knowledgable types?

I can think of a way but I wouldn't do it. If you got it wrong you would have an unregulated gas escape at 13bar (200PSI), thats double what I use as service air for pneumatic tools and just under half of what we use to start a 3 storey diesel engine.

This aint nannying but I couldn't in good conscience tell someone how to go out and potentially kill themselves.

Meh, you're nannying   If I'm gonna worry about things exploding then I'd be more nervous about the 90litre LPG tank behind my driver's seat

In all seriousness, all I'm after is something like http://www.nothingbuthardware.com/579130.html with the right connectors on it?  The worst that can happen is that one of the connectors fails and all the air comes out.  I would obviously make sure that the tank I buy is rated far in excess of what I'd be using!

Big Drop/Mr Ed: re electric ones - would I be able to happily run it off of a car battery when I'm at a DH race?  And do they have anywhere near the flow of air that I need?  For instance, if I try inflating from a service station air pump, most of the time it doesn't work.  If I go to a kwikfit or something where they inflate tyres for a living it's the easiest thing in the world.

IIRC 1hp = 750W, so a 1.5HP electric compressor = 1125W, assuming it runs at 100% efficiency, so probably nearer 1500W.  12v at 1500W = 125amps.

So if I buy that I'm going to need one f**k of an inverter, and some sort of magical car battery that can cope with that ampage.

thing is, how much compressed air do you need, charge it when your at home, and take it with you full... that way your good to go all weekend...
ed

Mine are fine using a cheap track pump.  True, it does take a bit of pumping to get them to ping into place, but not as much as trying to pump up a completely flat 2.5" DH tyre with a mini pocket pocket pump!

Find an old powder fire extinguisher. The older ones that came in entirely blue (as opposed to the new ones which are red with a blue sticker). The 3? litre ones have a screw off head so you can empty then completely clean it out, have a schraeder valve built into the head so you can charge it with a compressor or your track pump, have a built in pressure gauge so you know how much is in your bottle. Only thing you have to do is chop the nozzle off the end of the pipe and adapt something to fit to your presta valve.

I've got one and it works a treat!!! 

aldi do one for £40 never let us down an someones even sprayed a car with it