Our tire size is about to down from 28 to 25 and it seams that 16gr CO2 cartridges will not be of much help if we have to repair a flat on the road (it wasn't great from the beginning but the 28 tires can run lower pressure).

I've been shopping but can't find anything satisfying: I want a pump that works well, will pump up to an actual 135psi and that will not offend my minimalist-CO2-cartridge-user's eyes.

Any recommendations?

Topeak Road Morph

https://www.topeak.com/products/Mini-Pumps/RoadMorphG

Best pump I've used. Has all the characteristics of a floor pump.

I've been using a Topeak Road Morph G Master Blaster... it will get you all the PSI you need and does it pretty quick....it may not be minimalistic enough for you but it is not bad for how effective it is...size is about 13'' long with a 1 to 2 '' round cylinder and weighs 220 gr.

Bill J.

I buy the 12g CO2 cartridges from places like Big 5 sporting goods. Less than a dollar a piece.
Use two of those, or get a minimal pump and pump up the tire to 40 psi or so and then one CO2.
I was using a Blackburn Airstick. Pretty small and light but difficult to get up to even 100 psi.

+1 on the Topeak Road Morph. It's small, but easy to use. I also very much appreciate the gauge. I suppose it's why we carry one on every bike we ride (see sig).

Cheers!

But are they threaded?

Un-threaded. I use an inflater with a chamber that handles the un-threaded cartridges.

135 psi?

Yup. Max pressure for my new set of tires.

Use two CO2 cartridges per flat would work; thing is I don't want to change my name to twicethecatridges : I always carry enough for at least two flats... That would make for a huge seat bag.

I did salvage some Road Morphs from the garbage at work (guaranty returns), maybe I'll try an resuscitate one.

Did anyone try the Blackburn Frame CF pump? I think that may be just what I'm looking for...

I'm not sure I'm following the logic here. There is the same amount of gas inside the tire if you empty a 16g cartridge into a 28mm tire or a 25 mm tire. Thus as the volume of your tire decreases going from 28mm to 25mm, the pressure from a given size C02 cartridge will increase.

In our experience a 16g cartridge puts plenty of pressure into a 25mm tire. Of course we also don't run our tires at 135psi.

Merliextralight: Your logic is quite right; mine is that I am comfortable with riding my poorly inflated 28mm to the car/home with only 16gr of CO2; I don't feel comfortable with the same amount of gas in a 25mm because of pinch flats and rim damage risks.
I guess this would depend on the condition of the roads -- here, they are bad; enough so that I'm not sure that the 25mmm tires will stay on the bike long enough to wear...

You made me wonder and I did a search. It looks like a 16gr cartridge should bring a 700x25 tire up to 120psi -- which is much more than I thought and enough for me... As soon as the tires arrive, I will sacrifice a cartridge or two and run some tests. I will post the results.

Twice,
The 16gr will inflate a 28mm tires hard as a rock in our experience. Haven't measured the pressure, but certain 120psi or so. I do like my Topeak Road Morph, however. CO2 is a backup.

THat may be a good idea. Just watch out! We blew a 28x700 continetal gatorskin with tha method.

The Topeak Morph si the way to go for us... best frame pump we ever used, hands down.

I broke Two Road Morphs and gave up on them. I have the Blackburn Frame CF pump. Fits perfect and works great.

Have not needed 135 psi, but it seems like it could get there and is rated to 160. Very minimalist, efficient (threaded) and good looking if that matters. From Soma Fabrications.
https://store.somafab.com/soatmipu.html

In our 35+ years of tandeming we have found the Topeak Mt. Morph and Road Morph to be the best so far.
The Mt. Morph is a bit lighter/shorter than the Road Morph version. They are by no means a 'minimalist' pump, but they certainly are up to the task. Max pressure claimed: 160 psi.
On my single bike I carry a Quicker mini/pocket pump, claims to be able to reach 154 psi, but it takes a lot more pump strokes than the Topeak.
With Topeak we can get 100 lbs of air with 100 easy pump strokes in a 700x25 tire. The Topeak is actually a floor pump in disguise!
*Almost* a pleasure to get a flat . . .
Just our experience.
Pedal on TWOgether!
Rudy and Kay/zonatandem

One thing to keep in mind about CO2 is the molecules are smaller and the air leaks out of the tube faster.
So the next day it will feel like you have a flat, no big deal if you are at home with a floor pump, but on a tour you might want a good frame pump for that reason.

hehe! I have, (and use), the Road Morphs on our road bikes, the Blackburn CF frame pump on one of the tandems and a Zefal on the other, and CO2 on the fixies. All are satisfactory, although for a pump, the Road Morph wins the "ease of use" category in my book.

I don't know think I have heard very many who have broken the Topeak pumps.

What broke and under what circumstances?

The tab that folds out to step on to use it like a floor pump and the collar where the pump shaft goes into the body - both developed cracks and then failed.

I think the foot tab failure was what I had read about previously, IIRC. I had not heard about the collar failing.

That's a shame. Good pumps, by all other accounts. I have them, but have never had to use them in two years, knock on wood. I should try them out next time I need to air up.

Blackburn Airstik SL is very light (58g), and fits in seat bag easily. Takes a while to reach 100 pounds plus, but it does work. Makes a good emergency backup to a C02 cartridge.