Strange how many people disagree on CO2. Back in 05, I did 23 centuries. I had a triple crown ride partner that I did a few centuries together. He swore on CO2 and actually dissed my big long Zefal carbon looking full frame pump. I thought it was cool.
He carried 4 cylinders of CO2. He had a flat about 60 miles into the ride. Then he realized a mile down the road that he had a second puncture he didn't notice. THEN, he botched the job and flatted again about 1/2 mile down the road. THEN, he had a front flat about 15 miles down the road. There went his 4 cylinders.
Believe it or not, he had another flat. Bad luck I would say. So he had to bow down to my pump ha ha! I'm pretty sure he was really happy that I carried the full size pump. Easy to hit 120 psi with the pump.
Good technique makes the pump an easy tool to use. I have a crouched stance with my back arm up against my back knee that works great. An old guy way back in 1996 showed me how to efficiently use a frame pump. God rest his soul!
So never had a problem but I have seen some clowns, my ride partners try to use a pump and they honestly have no idea. Once clown stood straight up holding his rim with pump straight up pulling down on the handle side. WTH! Some have been so comical that I have just taken the job from them and completed it so that we could be on our way. I mean after 20 minutes of clowning around, forget about it, just let me do it!
I used CO2 in the past but been let down a couple of times so I don't depend on it. Once on the tandem, over 100 degrees, I inserted the CO2 and maybe it was the difference in temps, the stem froze around the rubber and actually snapped off. It hardened the rubber and it just broke. Another time I got a dud. That sucks!
I did like my full size frame pump and still carry on the tandem. But my latest roadie has a sloping top tube with a radius so the straight pumps don't fit right in the frame. I did get a Lyzene small frame pump that fits alongside the water bottle. It works OK, up to 90 psi which is good enough to finish a ride but not like the full size.
It also has a screw on hose attaching to the presta valve so no worries about it slipping off or breaking the stem.
I am sure there are positive and negatives for both but I prefer a pump. Haven't had one fail me yet.
Hardly noticeable on my bike. Good mounting bracket lined with rubber so no slip etc.
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