General Cycling Discussion - Bike pump gauge showing low pressure

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




jagot
10-17-11, 05:25 AM
Hi,

I'm pretty new to cycling (haven't done so for about 15 years), and I've recently got a bike to speed up travelling to uni. I have a bike pump with a gauge, but I'm slightly worried about trusting the gauge on it.

My tyres are rated for 50-85 psi, and I'm currently hitting around 40 and they feel pretty solid to me, and I'm feeling some resistance on the pump at the moment and I can hear the spokes twanging every now and again, so I'm rather concerned that trying to pump it up between the specified range might be too much for it.

Should I go any further with it? Could the gauge on the pump be wrong?

This all is probably because I'm inexperienced, but any advice on the matter would be helpful!

For reference, this is my bike:
http://bit.ly/mRuFTW

And this is the pump I'm using:
http://www.amazon.co.uk/gp/product/B0010VPLZ2

Thanks in advance.


10 Wheels
10-17-11, 05:36 AM
Borrow a pump or guage from someone and see if it matches your readings.

Juha
10-17-11, 05:41 AM
Cheers, welcome to Bike Forums!

When you say "they feel pretty solid", what do you mean? Can you squeeze the tyres with your fingers noticeably? Pump resistance is OK, you should expect that as the pressure goes higher.

Regarding the twanging sound of the spokes, have you ridden the bike much yet? It would be good to check spoke tension after initial set-in period (a couple of hundred kilometers should be enough). Spokes may be loose or unevenly tensioned.

--J


jagot
10-17-11, 05:45 AM
Thanks for your responses!

I'm afraid I'm not sure I know of anyone with a pump with a gauge on to test it, but I shall ask around.

Juha, when I push directly on the tyres they feel pretty solid to me there, but I can noticeably squeeze them with my fingers at the sides and they do go in a bit. So I assume that means that they can be pumped some more? I guess my idea of the tyres being solid, compared to someone more experienced might be completely different!

I've probably only put about 30km on it so far at most. Don't know too much about bike maintenance my self, but am certainly up for learning!

Machka
10-17-11, 05:55 AM
Go to a bicycle shop and ask them about both the tire pressure and the spokes. Take your pump with you so they can show you how to use it.

atbman
10-17-11, 04:50 PM
Even if the gauge is slightly under-recording the pressure, you will have to pump very hard to create any real problem, such as blowing the tyre off the wheel (never happened to me).

Just pump it up to the recommended pressure and you'll be ok - and roll more easily

jagot
10-23-11, 07:02 AM
Thanks again for the further responses. Managed to speak to someone who knows a bit more about bikes than me at my uni, and he said my tyres weren't inflated enough, so I've now pumped both up to 80 psi and they're fine.

Vras
10-23-11, 11:46 AM
For me, a separate tire pressure gauge is always useful to double-check gauges fitted on bike pumps.

Auto shops and even Walmarts sell them for under $3 each - though you might need an adaptor (Shraeder to Presta) if you have Presta-valved tubes. I use one that I normally carry/stow in my car's glove box to check my bike tires before each ride - only relying on the bike pump's gauge if I actually need to add air.

vredstein
10-25-11, 01:28 AM
Hi,

I'm pretty new to cycling (haven't done so for about 15 years), and I've recently got a bike to speed up travelling to uni. I have a bike pump with a gauge, but I'm slightly worried about trusting the gauge on it.

My tyres are rated for 50-85 psi, and I'm currently hitting around 40 and they feel pretty solid to me, and I'm feeling some resistance on the pump at the moment and I can hear the spokes twanging every now and again, so I'm rather concerned that trying to pump it up between the specified range might be too much for it.

Should I go any further with it? Could the gauge on the pump be wrong?

This all is probably because I'm inexperienced, but any advice on the matter would be helpful!

For reference, this is my bike:
http://bit.ly/mRuFTW

And this is the pump I'm using:
http://www.amazon.co.uk/gp/product/B0010VPLZ2

Thanks in advance.

I build bikes like these all the time. In my experience, the upper end of the rated psi range printed on the tire is quite a bit higher than most people would need. Unless you're a bit over 200 lbs, 60 psi is enough. 80 psi will give a harsh ride. The tire may skip and jump over every small bump. Getting a second air gauge is a good idea. The "pencil" type gauges used for car tires are worthless. You should get something like this-
http://www.getagauge.com/Tire-Gauges/Accu-Gage-S100X.cfm