Bicycle Mechanics - CO2 Pumps

Hello.

I was thinking of buying a CO2 pump for out on a ride if I get a flat. Will one CO2 canister fill a tube??? It seems such a small container.

One regular size canister wont fill a tube by itself. You can get just the nozzle, and threaded canisters that are larger than the normal ones also.

Road tires or MTB?

get the genuine innovations brand or something similar. If you get the right type, they can take any generic CO2 cartridge. They also sell larger cans that can fill a lot more. My understanding is though that one lil cartridge, dunno the size, will fill at least one road tube.

I just bought an SKS "Airchamp Pro" (which, despite the name, is a C02-cartridge pump).

The packaging claims that it will fill
a) MTB (26x1.95) Tire to 3-Bar/43psi
b) a 700 x 32 to 5-Bar /72 psi
c) a 700 x 20 to 10-Bar/144 psi

When I bought it, I asked my friendly LBS owner whether he thought it would be sufficient. He responded that it would sufficiently fill my road tires (700 x 23) to at least 100 psi. But, the way he answered the question betrayed a wee bit of skepticism about other applications (presumably wider tires). I didn't think to inquire further.

You could always carry two cartridges. As long as the mechanism will handle the pressure, the only question is volume.

In any case, I have two other SKS pumps (a floor and a frame pump). They are super reliable. I don't know whether they are available on the other side of the pond.

Cheers,
Jamie

As Guillermo said, the Innovations is a good choice. If you want to go really minimalist you can take just the head and a couple of threaded cartridges. The threaded cartridges are a little pricey. For normal use you can use unthreaded cartridges, buying a box of air rifle cartridges from Wal-Mart at MUCH lower price.

After using CO2 you are supposed to deflate and reinflate with a pump when you get home.

I find that I can fill a road tire to about 90 psi with one unthreaded cartridge. That is plenty to limp home on.

It takes about 3 unthreaded cartridges to inflate a 26 x 2.25 in MTB tire to 60 lbs.

Threaded cartridges are spendy but hold more gas. I've never used the Big Air cannister.

Normally I carry a CO2 inflator on my road bikes and a mini-pump on my mountain bike.

A dissenting opinion - I've used these things and nothing beats a good, compact pump. The CO2 can be nice in a race. I am also impatient and lazy when I am on a ride - bad when you are dealing with these finicky little devices. :D

I tried CO2 and am back to frame pumps. Here's what happened.

Cruising along on the backside of an evening recreational ride, hit a chunk of gravel. Hissssssss. Flat tire. No problem-o! I've got a spare tube, CO2 thingy, and 2 cartridges. Normally, you inflate the tube just enough to give it some shape before mounting, right? I didn't, because I didn't want to waste the CO2. Consequently, upon inflating the tire I found that I had pinched the tube while mounting the tire and now it was leaking.
:(
No worries! I've still got patches and one cartridge left. 5 minutes later, patch is in place, tube mounted, and I'm putting another cartridge in my CO2 thingy when the plastic cracks near the trigger mechanism. Maybe... if I'm real careful.... hissssssssss.
:eek:
Fortunately, I was near some houses, and someone was at home at the second house I went to. Long distance, so I use 1-800-collect and thank the resident profusely. The bike widow was home, and I only wound up walking a mile or so in my cleats 'til she arrived.

Ultimately, it was a series of SNAFUs. Maybe if I'd been more careful with the first tube, maybe if I'd bought a better quality CO2 pump, there would be no story to tell. My reaction was to go to the Topeak web-site, and order a Road Master Blaster, and give my remaining CO2 cartridges to a friend. A week and a half ago, during a club ride, I had two flats. One on the way, one right after the finish. Thanks to tubes, patches, and the RMB, this time there was no story to tell.

YMMV.

i carry two 12gm cartridges. a 12gm will fill a 700 x 23/25 tube to 90-95 psi. i carry a small adaptor and slowly fill. they are great. the only problem i've had is with turning (activating) the co2 and blowing the new tire off (a kink the tube?)

you've got to be careful with the 16gm one's on standard 700x23 tires. if you don't know to choke it off in time you will blow the new tube clear off.

I tried CO2 a while ago. It left me stranded. Never again.

Never say never. I was too vain to put a pump on my bike, so I went back to C02. I've had good success.

Most importantly, I've resorted to buying good quality tires and tubes. The few extra dollars I spend come back several fold in time savings.

I use both Conti tires and tubes.

I use CO2 for the road bike with 12g cartridges. Being fundamentally lazy, I hate manually pumping alongside the road. I rarely have flats, but I love how quickly the CO2 fills. I carry two cannisters, though, and nearly got stranded this past week when my spare tube had a slow leak. There are always compromises.

With the MTB on a trail ride I carry a mini-pump in my Camelbak, since there are no houses with 'phones in the woods should the CO2 fail (or I fail).

Finally, in an XC race it's CO2.

I use the The Second Wind IH. This is a CO2 inflator combined with a mini-pump! It fits both Presta and Schreader valves. Includes one 16g threaded cartridge. I have had great luck with these.

Nashbar has them on sale (item - IN-SWIH) $19.99

http://www.nashbar.com
Look under pumps/co2

This really works great!

http://www.nashbar.com/productimages/medium/IN-SWIH.gif