Tyre pressure for bicycle 28 September 2018 at 9:46PM in Public transport & cycling 24 replies 3.4K views

JustAnotherSaver

A hybrid bike if it makes a difference.


Wife had a flat on hers & did a google search to find it 'should' be somewhere between 40psi-70psi. I had a look at the tyre & it said the max pressure for it was 45-80psi.



It has one of those presta valves. I set to it pumping the thing up & i just can't get it over 30psi no matter how much i try. The pump isn't anything special, it's one of those small emergency type pumps. The gauge is the Topeak D2 Digial Gauge bought new. I tested it on my car tyres vs another gauge i have & it was within 1psi so while it may not be perfectly accurate i'm sure it'll be somewhere in the region.



Tried and tried to get it over 30psi but just couldn't and the tyres do feel quite firm at that.


Tried the gauge out on my hybrid bike. Admittedly it hasn't been serviced at the bike store since a couple months after i bought it last summer but the rear was reading off at 23psi and the front at 22psi. Quite a bit of what it 'should' be according to Google, though i do appreciate it can/will leak over time.






Now i'm no cycling nut, hence why i'm here hoping that there are some cycling nuts who'll read this.


What would you have the psi at?


I suppose it'll vary on things. Body weight, where you're travelling etc. To be honest we should've bought road bikes i guess since that's all we've ever used them for. I'm about 165-170lbs and my wife will be lighter than me.

Johnmcl7

I'd go more by feel for that sort of tyre so you want it high enough the tyre is firm but not too high it's uncomfortable to ride particularly if you ride off road and want a little give in the tyres. For my road bikes because I only ride them on the road I have the tyre pressure firm so when I squeeze the tyres they're quite solid. Before I ride I give them a squeeze and if they feel a bit soft, I just pump them up to full.

I have exactly the same tyre gauge and primarily use it on the fat bike and plus bikes as precise tyre pressure is a lot more important on them. It seems fairly accurate for them and also seems accurate when I've tried it on car tyres however I was trying it on a normal mountain bike and it seemed to be giving far too low a figure. I'd say from feel the tyre pressure was in the mid 20's but the pressure gauge was saying they were around ten psi. I've not tried it on the road bikes because the exact pressure doesn't matter, they just need to be firm.

I'd recommend getting a track pump as they make it much easier to deal with presta valves, the flexible tubing means you can pump up the pressure without it coming loose from the valve and it usually clamps better onto the valve. I bought a small hand pump when I bought a bike with presta valves but found it difficult to get the pump properly clamped onto the valve and pump it up while keeping it clamped on the valve as it was very easy for the air not to go into the tyre.

John

esuhl

I ride my mountain bike on the road, mostly, and have my tyres set to around 42psi. I'd probably drop that a little (~32 to 35psi) if I was riding off-road more.


I think road bikes, with their slick, narrow tyres require higher pressures.


A track pump is invaluable -- they're so quick and easy to use, compared to the fiddly huffing-and-puffing that a pocket pump causes. I got one from Halfords last year for £17. It has a clear dial, quick release, and automatically adjusts to fit both Presta and Schraeder valves.

Norman_Castle

I've got a few hand pumps, a few foot pumps and a track pump. Its only with the track pump that I can easily get higher pressures. I normally inflate to 65psi which I suspect is about right for a hybrid bike being used on the road.

[Deleted User]

Hand pumps can be useless, and they are slow. My Topeak Joe Blow max hp hand pump was nt expensive and easily pumps my narrow road bike tyres to over 100 lb pressure.Also it can pump my car tyres up if needed. It is now £23 on Amazon. I can vouch for this pump, had it a few years now and still as good as ever
I had several hand pumps which could nt pump up my low pressure folding bike tyres at all.

chris_n

Hand pumps are for roadside repairs, get a track pump and put about 60psi in them. They will roll better than at 30 psi, that's only any good for mountain bikes.

[Deleted User]

surreysaver

I've got a Brompton. I weigh 102 kg. I keep my tyres at 110 lb/sq inch

JustAnotherSaver

Just a thought here ...


What about a presta-schrader adapter (at a few quid it's much cheaper than a bike pump) and a 12v compressor (already own one)?


Adapter on, pump it up with the 12v, take adapter off.



Or is there a reason that's a bad idea?

Lorian

my hybrid runs at 80psi. need good rims and tape, and I always inflate with my back to it - having experienced one go bang.

Are you sure the you've unscrewed the presta fully, and depress it a few times to make sure its free to go down.

Then when attaching the pump the presta needs the latch down while attaching and then pulled up to pump which is the opposite way to the Schrader (Car) valve. i

JustAnotherSaver

Lorian wrote: »

Are you sure the you've unscrewed the presta fully, and depress it a few times to make sure its free to go down.

Yes. Or at least i've done it how a YouTube how-to showed me

Then when attaching the pump the presta needs the latch down while attaching and then pulled up to pump which is the opposite way to the Schrader (Car) valve. i

Took a bit for me to get it to 'lock on' but managed it in the end.