I'm interested in switching from my frame pump to a CO2 inflator. Will a 16g cartrdige have enough air to inflate a 700c tire to 120 psi after inflating it a little and then deflating it to prevent a pinch flat?

Thanks!

yes

or save money and get 12g ones from wal-mart, will get you to about 90PSI which is enough, they cost less than a buck each!

yeah, 12g cartridges are plenty. Best method I've found for more than adequate inflation: (i forget what kind of co2 inflator i have, but it threads onto schrader valves, but not presta). Screw schrader adapter to presta valve, screw inflator to schrader end, screw co2 cartridge into inflator. Everything in the system is sealed pretty well, and there's virtually no loss, and no worry about somehow not having enough CO2 per cartridge.

also, I usually have some leftover in the cartridge, which can make for a fun practical joke of spraying your riding buddy on the back of the neck or knee with a cold spritz of CO2. (use at your own discretion)

What size tire, 23 or 25? I'm inclined to say no, it would probably not reach 120psi if you deflate the tire after a quick shot and then inflate again from the same cart.

Why are you deflating? Put a little air in the tire. Check to make sure the tire is seated everywhere, and fill it up. I've never had a problem doing this.

Normally, when I hear pinch flat I think of a flat caused by hitting a bump and having the tire bottom out on the rim pinching the tube and creating two small holes i.e. "snake bite". I presume you're referring to having a small portion of the tube protruding out and pinched between the tire and rim. I just visually inspect the tire to make sure this isn't happening.

23

Just my preference. After a full deflation the tube seems to get "unpinched" better than just checking it over.

In that case, carry two.

oh, didnt even see the thing about using some, then deflating.... idk if that works, but its unnecessary, as described above. if you really want to inflate it some to check, maybe carry a crappy micro pump to augment your CO2 use - just enough to check things out, let the CO2 do all the work, but youll have the pump onhand if things get really dire?

Yes, I inflate, bleed it down, then inflate to 120 psi, still have some left.

Oh and carry at least 2, I carry 3 or 4 if going for a long ride.

I usually just give it one little shot to give the tube some body and then put the tube in, haven't had any issue with pinch flats. I carry 16 gram cartridges, and while I don't know how high the PSI gets I don't need to use the whole cartridge to make the tire feel fine to ride home on. I decided to get the "full feature" CO2 inflator that has a hollow handle that serves as a place to store the cartridge as well. I've heard you can get frost bite if you're not careful with the tiny one. I don't much care about the minor additional weight and it seemed like an easier route to take. I usually carry three cartridges which is probably overkill, but they fit in my jersey fine, and I don't care about the additional weight, so why not?

I just flatted yesterday for the first time since I actually bought the co2 inflater and cartridges. I did pump up the new tube a bit with my mini pump, both to give it shape and give it a head start once it was seated. I used 1 16g cartridge and the tire (23) was rock hard and the cartridge got very cold, which was welcome in my drippy sweat.

Much much much better than pumping the mini pump until my arm falls off, which is what I did in the past.

One suggestion that I'll do in the future is to include a couple of packets of "wet ones". They are similar to the old KFC wipes (napkins with some cleaner fluid built in). Since my rear tire flatted, I got my hands very greasy with the chain. Did my best to clean them off, but managed to get my white bar tape a bit dirty.

Put your tubes inside a zip bag with talcum powder. This will enable the tube to "roll out" inside the tire easier and helps to slip away from pinches.

Bring rubber or nitrile gloves and put it in with the inner tube bag.

BRING MORE THAN ONE CO2 CARTRIDGE. You will be as mad as I was when you happen to screw up inflating it.

You could keep your chain clean instead of carrying the wipes. Shave grams on both wipes and chain gunk.

Orr, have you tried black bar tape? It does a great job of hiding rear-flat repair "evidence".

You can remove your rear wheel without touching the chain.

edit: You can also install it without touching

I too have white bar tape, and a white saddle. I now carry a latex glove rolled up in my bag to avoid just such a situation.

To my surprise a little citrus degreaser easily brought back the white bar tape after a messy incident just like yours.

Some of us aren't that good :-P

Removal: shift rear DR into smallest cog, release QR, then apply pressure with right hand middle and pointer finger onto derailleur cage to release tension, then push both sides of the QR down to release wheel from dropouts.
The installation is easy enough to figure if you can remove it without getting dirty.

I can remove the wheel without touching the chain, for some reason I always have trouble with the chain getting in the way putting it back in.

I find that putting the RD to the middle cog is easier than putting it in the smaller cog.

I have a dumb question...Will a CO2 cartridge lose air if you don't use it? It's been months since my last flat (knocks on wood) and I've had the same 2 cartridges in my bag.

It just occurred to me it is probably easier to put the rear wheel back in with the bike right side up...

I can't. As much as I'd like to. Plus, I managed to knock the chain off the front derailleur in the process after getting the wheel back on and skewer tight.

No. but honestly, I don't know if anybody has actually done a study on how long CO2 cartridges last without losing its charge. I've had one for a few years and it still worked when I needed it. After that I just lost track of how long I've had the cartridges.

Yes it is.