Inflating Using a Mini-Pump

[02GF74]

Last time I used a mini pump it broke in my hands and accidently punched the wheel and cut my hand.

Had an accident that is not your fault? Then call 0791 888 321

 

[02GF74]

..... back to the OP. without seeing the pump and how you are using it is is difficult to advise. my pump is smaller than yours Na-na-na-na and lighter too (it is carbon fibre) and although I have only used it in anger once, it will inflate an mtb tyre eventually. (eventually as there is a compromise with size/weight and inflation time). It takes maybe 5 mins, if you are pumping away for 40 mins then something is clearly not right.

Advice to anyone with a mini pump, try it out so that you know it works and know how to use it before you really need to use it.

 

[I like Skol]

.....

Advice to anyone with a mini pump, try it out so that you know it works and know how to use it before you really need to use it.

X2
I have a small Topeak one and it has been great. I used it to inflate the tyres of my new road bike before I bought a track pump and it went from not firm enough to Kin'ard in just a couple of minutes. I didn't know what pressure I was acheiving but comparing it too the track pump suggests I was well past 100Psi. I tried it out as soon as it arrived to make sure it worked and have since used it in anger by the road side with no problem (other than it pi**in down with rain so no pump was going to be fast enough).

If you are not getting a typical road bike tyre up to a rideable pressure after a few minutes then something is wrong. I guess it could be a longish slog to inflate a big MTB tyre but they only go to lower pressures so again I would expect to be riding after 5 or 6 minutes of pumping at the most?

 

[Octet]

I don't feel air coming out of the end (even when placing it next to my cheek, and there doesn't seem to be any resistance when I try and pump with my finger over the end.
It makes the sound but I don't feel anything, not sure whether I should feel resistance or whether it is designed not to have resistance?

 

[I like Skol]

There is something wrong with your pump. Either it is faulty or you are using it wrong. Re-read the instructions and try again.

 

[Octet]

Ok,

I completely deflated one of my tyres, followed the instructions exactly.

Close the Pump Air Rush Valve (used to switch between CO2 and normal pumping)
Open the Presta Valve
Insert Pump into Presta Valve
Pump

Tried for ten minutes but no inflation what so ever. There is the smallest amount of air coming from the pump, when I say small... I can stick the pump next to my eye and pump without it causing the eye to dry out or become even the slightest bit irritated (Doctor probably would have something else to say about that... but providing I don't do it with the CO2).
I don't think it is going into the tyre, because there isn't enough of it to push through so to speak.. but that is only a wild guess.

I think I may have also bent the pin on the Presta valve now... woops

Pumped it up with the track pump though, 110 PSI and then a small amount lost as I removed the head to get it back to about 100 PSI.

 

[Octet]

I think I shall just go for a new pump, anyone got any recommendations?
Preferably one that can mount onto the frame (trying to get away from carrying a rucksack).

 

[endoman]

Done my last 7000 miles with just CO2 while out on the road, 2 carts and 2 tubes every trip. Had to use one today, hassle free inflate to 120 psi, total 5 minutes. Have some mini pumps at home but use the track pump. I inflate the tube orally to get it seated then the CO2 is a doddle.

It does sound like your pump is faulty, take it back and get a replacement, try it in the shop to be sure. A small pump will fit in a jersey pocket along with a tube or two.

 

[Octet]

Shall take it back, I don't have the original packaging or receipt unfortunately but hopefully they will take a look at it.
The CO2 worked fine, just the hand pumping part of it.

 

[Octet]

Being a tinkerer at heart, I decided not to admit defeat!

I dismantled the pump, taking off the valve/head bit at first and then testing it. I did notice a sort of squelching noise which would suggest that there wasn't a proper seal on the plunger!
Next step was to dismantle the plunger, slightly tricky as they used a special tool to fit it in but I managed to unscrew it by jamming a screw drive into it and twisting the handle (warranty was void by this point so I was kinda hoping it would work once I had 'fixed' it).

I took out the old O-Ring and wrapped some floss around the plunger bit, then placed the O-Ring back on so that it pushed against the sides more.
I didn't have any proper sealing and lubricating oil so I just used WD-40, and then re-assembled it, again by jamming in the screw driver and then putting the head back on.

It seems to work now (yet to test it on the bike), it was a poor seal on the plunger against the shaft... and that is your idiots guide to home pump repair

 

[02GF74]

hmmmm, how about fitting a new o-ring? they can wear and harden with age - i managed to fix a rather expensive and nice track pump that way.

also ask yourself whether you trust your repair, the last thing you want s to go on a trip by yourself, all smug like , get a flat and find the pump does not work.

 

[Octet]

Hehe, that would be a nightmare.

I got a handful more CO2 which I would rather use (carrying four in total now), and I shall get onto ordering a new O-Ring as soon as possible.

Although just in case, I shall carry a white flag

 

[TheDoctor]

I would advise wiping the WD40 out of the pump and using a smear of Vaseline instead.
WD40 will rot rubber, and you'll be spraying a mist of it into the inner tubes.

 

[Octet]

I would advise wiping the WD40 out of the pump and using a smear of Vaseline instead.
WD40 will rot rubber, and you'll be spraying a mist of it into the inner tubes.

Oooh, shall do that quickly now, thanks for the heads up!