Any question answered...

Presumably you'd be pressurising it so the chamber size could be smaller.

No, I dont think so. Just a massively oversized pump.

So I could make a one shot bike pump with a chamber size of somewhere between 4 and 14 litres

You could make one, but you probably couldn't operate it by hand. Consider the case of a 29"×2" tube or tyre; to fill it in one stroke of the pump cylinder, you would need a 2" piston and a stroke of 7'6". That's fine if you lay it down and walk across the floor pushing the handle, but the end of the second stroke taking your pressure up to 1 bar gauge pressure would need a driving force of 46lb. The next stroke ends at 92lb. You quickly run out of grip on the floor. If you want to make it upright at a somewhat manageable stroke length of 24", you need a piston diameter of just under 4", so you need to weigh nearly 200lb just to stand on the piston and generate 1 bar gauge pressure

My LP pump has a bore×stroke of 1.5"×20" and a maximum pressure of 6 bar. If I sacrificed pressure capacity to volume, since I never need more than 3 bar in LP tyres, I could increase the bore by a factor of √2 to give the same operating force at maximum pressure. That would yield a stroke volume of 70in³ or slightly over one litre. That seems to be a reasonable practical limit, so keeping the stroke at 20" (500mm), the pressure-volume product should not exceed 3 bar.litre

Since there are always 100 ways to skin any particular cat, you can look at the problem from an energy perspective. The energy stored in a pressure vessel (idealised isothermal system) is

In this case:
p_A = 0.1MPa (1 bar ambient pressure)
p_B = 0.3MPa (3 bar absolute pressure in tyre)
V_B = 0.004m³ (4 litres tyre volume)

If we evaluate
0.3 MPa × 0.004 m³ × ln(0.1 MPa/0.3 MPa) + (0.3 MPa − 0.1 MPa) ×0.004m³ = 518J

The pump stroke energy input will have to be a bit more than that to account for losses, but the integral of force over distance must be at least 518J. For the practical maximum stroke for a manual floor pump of about 0.5m, the force will ramp up from zero to just over 2kN. Obviously, if you weigh 2kN you will need more pressure in your 29"×2"tyres that 2 bar gauge, so you end up chasing yourself in a circle 🙂

This leads to a practical guide to #whatpressureyourunning , since the energy stored in your compressed air will always be quite close to the product of your weight and height, e.g. 100kg and 1.85m gives 1800J, compared with 1700J for 2.5 bar gauge in a pair of 55-559 tyres or 1500J in a pair of 25-622 tyres at 6 bar gauge

Would microshift 12sp thumbies work ok with 11sp rival mech? I can't seem to find 11sp sram version anywhere in eu, so thinking would 12sp version would do a job?

The opposite seems to work, 11speed thumbies with Eagle 12speed - https://bicycles.stackexchange.com/questions/44178/sram-x01-eagle-12speed-in-11speed-transmission-it-work

Is Tektro CR720's cantis a faff to set up with the yoke that comes with?

A pump set up like this, where you move a handle from A to B was my thinking. Who wouldnt want a one-shot tire pump? How long would the lever need to be?

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Yeah, i saw this. But no info if it would work other way around.

How long would the lever need to be?

There's no need for a lever, you just choose the pump bore to make the product of maximum pressure and piston area equal to the maximum force you can exert on the piston rod.

If you wanted to make a practical device to increase mechanical advantage in order to get the required pressure and volume from a single stroke, you'd use a capstan and a block and tackle, but adding all that friction just so that you can wind a handle multiple turns rather than reciprocating a pump handle multiple times seems silly.

The other alternative is to make the cylinder very long, about 5m should do so your device when extended would be just over 10m long.

Obviously, this needs replacing...

What is this bracket (system) called and what tool do I need to remove it? bearings were BB30 but there's an aluminium sleeve around it, screwed into the carbon bracket:

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I have an old bike that I have fixed up. I took it out for a spin (pre-corona ages) and couldn't get on with the small shifters. They are old campagnolo chorus ones. Are there any other 10 speed (campa) shifters that are bigger? Being used to the shimano hydraulic ones...

What happens if you get two BB tools on it and unscrew it?

If the bearings were 30mm ID then it's either a PF30 or T47 shell. You'll find out when you get whatever's left out.

This looks like it or similar.

Cheers, your suggestion looks a lot like it indeed. I do not have any tool with which I can unscrew that sleeve, yet, and I'm having a hard time finding them.

Of the left bearing, only some balls and the outer ring are left. I can't seem to get that outer bearing ring out, so the whole sleeve has to come out.

The crank fitted to it was a Shimano Ultegra (Hollowtech) so I imagine it must have had some adapters like these fitted to go to 24mm, but they were ground to bits by my friend :D

found it, this Twist Fit bb tool (the 48.5mm side) is what I need

EDIT: oh no I do not need this, for it does not fit :-(

The Campagnolo Veloce 10-speed shifters are bigger, like the 11-speed ones

https://www.wiggle.com/campagnolo-veloce-power-shift-10-speed-ergopower-2015-set/

Microsoft Office 2019 (licence) on ebay........trustworthy?

Unlikely

Don't know about Office but the Windows licenses work. It's usually some bulk
OEM licenses getting resold.

Microshift came back saying that 12sp shifters wouldn't work on anything but x-actuation. Rival is exact actuation so I guess back to hunting

thanks! now to decide if that bike is worth a 100 euro upgrade :p

I suspended my instagram account due to a security scare.
I assumed I could re-activate, like on Facebook. when I try to log back in, it either says my email does not belong to a user, or if I try to create a new account, it says my email is already in use.

The tricky bit is, as I don't have a smartphone, I use instagram on Safari on a mac, by changing the user agent to iphone. Any help appreciated.

Yeah, they might work, but they're not 'trustworthy' or in any way legit. Depends if you care really.