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Tyre inflation

I bought a 130psi hand pump.
I had to use it today.
I went to leave work and noticed my front was flat.
A Maxxis refuse 700*28c with an inner and outer tube protector. I pulled a 4 mm deep thorn from the tire, pulled the tube out, the tube appears to be non punctured so I reassembled and rode home. The rear had deflated too.
I guess a work mate is helping me learn..
Anyway having inflated both tires, upon getting home I added more pressure using a decent floor pump.
I seem to achieve 30-40 psi using the hand pump! Is this normal? I rarely get punctures, I can't remember the last tube that was punctured yet I wouldn't want to ride 30km upon the pressure achieved from my hand pump!
I use 2 road bikes. Both use the same front rim; a refuse 28. 1 rides both refuse 28. The other being tonights bike rides a session 28 rear (a lot more volume with no problems at 40 psi).

Did I get sucked into a did road bike pump?
A Samurai bbb/bmp-50 mini pump.

Any suggestions please per road side 100psi?
My best guess is to purchase a co2 inflator to do the effort bit of 30-100psi with.
Next best guess is a larger volume higher pressure pump.

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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23 comments

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madcarew | 6 years ago
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Couple things. An increase to 40 deg C won't explode the tyre off the rim. That is almost certainly solely due to poor seating of the tyre. Put the tube in, put the tyre on, pujmp to about 40 psi and rotate the wheel, make sure the tread is central all the way round and no significant bumps. explosions causing splits in the innertube are almost inevitably caused by the tube getting trapped between tyre and rim. 

If you're on 28's, 40 psi will get you home safely in most circumstances till you can pump it up proper unless you're in excess of 100 kg.

Your pump may be rated to 160 psi, but your arm almost certainly isn't. I don't know  anyone who could get 160 psi out of a hand pump. It's damn near impossible out of a floor pump unless it is small bore. I use a mtb pump to pump up my road tyres. on 23's it takes 100 pumps to get 90 psi. I can't do any higher than that. Small mini road pumps will take considerably more pumps, but with a narrow bore should be easier to attain the pressure.

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Boatsie replied to madcarew | 6 years ago
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madcarew wrote:

Couple things. An increase to 40 deg C won't explode the tyre off the rim. That is almost certainly solely due to poor seating of the tyre.

I agree. Problem I had might be caused by over inflation. My mate loves hard tires. Took about a year to convince him that 100psi is hard enough. Even offered him some old 17mm tires that I have hanging around with a smile and a, " go 4 it, they'll take 170."
Anyway, when his bike rode itself off, taking lock, chain and all, besides marveling that my mates black bike must have been that red led front kit bike and much smarter than us night riders, I lent him my crusty trusty. I never punctured the 28 on that bike with years and thousands of kms. I showed him and told, 80 plenty. Min-max, 80-110 psi. He kept puncturing. His like was 130psi.
After replacing bike, I put him onto refuse. Max 120psi. Blew the sidewalls out of them!
Now he's happy on 100psi and cruisy is on our many fresh layer roads.

Meanwhile, at quarter tread I might use the tire at 60psi locally although I think it's rubbish. Bead won't grapple rim very well anymore.
Happy to share story.. Down under, 40 ℃ day is much hotter upon tarmac. We watch the bitumen melting and some find it amusing to watch a cigarette wick melt a puddle on the road just prior to temperature naturally creating a large puddle.
Those tires get hot and at such high pressures they are already near their enclosed expansion.
Those reasons are why I feel safe 20 psi below Max on refuse.
I agree regarding 40psi in 28s. Slower ride though with lots less effort yet haven't trued rims yet (although heavy 36 spoke rim).
Friggin hot today! A different mates home is 48 ℃ and that shade, bitumen hotter!

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madcarew replied to Boatsie | 6 years ago
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Boatsie wrote:
madcarew wrote:

Couple things. An increase to 40 deg C won't explode the tyre off the rim. That is almost certainly solely due to poor seating of the tyre.

I agree. Problem I had might be caused by over inflation. My mate loves hard tires. Took about a year to convince him that 100psi is hard enough. Even offered him some old 17mm tires that I have hanging around with a smile and a, " go 4 it, they'll take 170." Anyway, when his bike rode itself off, taking lock, chain and all, besides marveling that my mates black bike must have been that red led front kit bike and much smarter than us night riders, I lent him my crusty trusty. I never punctured the 28 on that bike with years and thousands of kms. I showed him and told, 80 plenty. Min-max, 80-110 psi. He kept puncturing. His like was 130psi. After replacing bike, I put him onto refuse. Max 120psi. Blew the sidewalls out of them! Now he's happy on 100psi and cruisy is on our many fresh layer roads. Meanwhile, at quarter tread I might use the tire at 60psi locally although I think it's rubbish. Bead won't grapple rim very well anymore. Happy to share story.. Down under, 40 ℃ day is much hotter upon tarmac. We watch the bitumen melting and some find it amusing to watch a cigarette wick melt a puddle on the road just prior to temperature naturally creating a large puddle. Those tires get hot and at such high pressures they are already near their enclosed expansion. Those reasons are why I feel safe 20 psi below Max on refuse. I agree regarding 40psi in 28s. Slower ride though with lots less effort yet haven't trued rims yet (although heavy 36 spoke rim). Friggin hot today! A different mates home is 48 ℃ and that shade, bitumen hotter!

We're in the high 30's here in NZ too at the minute. Too hot for a decent ride!

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alansmurphy | 6 years ago
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The workstand is a bugger to get in your jersey pocket though...

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ktache | 6 years ago
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This is what I do and it might help to reduce pinches, I talkum powder both the tube and the inside of the tyre, put one bead on, the talk reduces friction, insert partly inflated tube, other bead on, then inflate to around 20psi, then with the wheel lying on the floor or in the bike in the workstand, fully deflate before pumping to the desired pressure.

Bit messy, powder goes everywhere, but it works for me.  Oh and wipe the talk off the rims .

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arckuk | 6 years ago
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I bought a mini pump about 5 years ago, and haven't had to use it yet... Always carry a spare inner tube and a single (or two for a longer or rougher ride) CO2 cannister. I mostly used Continental GP4000S II 25 mm tyres at 80-90 psi, and suffered a total of 3 punctures last year, in ~ 14,000 km mostly riding in and around London. Track pump at home means weekly pressure checks aren't any hassle.

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gthornton101 | 6 years ago
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I carry a Topeak Mini Morph as my mini pump and find it excellent, can comfortably get tyre firm enough to ride 15-20km home without giving it a second thought.  What I really like about the pump it has a short length of "hose" so you are much less likely to snap the valve off (as I did with previous mini pump that attached straight on) and it has a tiny flip out footstand so you can lean it upright on the pavement to pump!

If time is an issue though, you can't beat co2 inflator for getting back up and running to 100psi in all of 3 seconds.

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alansmurphy | 6 years ago
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Lezyne pressure drive hp pump is the best I've found for going beyond 60psi.

Fella, get some winter gravel tyres at about £15 a go, you'll save money, the planet and your sanity!

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Boatsie replied to alansmurphy | 6 years ago
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alansmurphy wrote:

Lezyne pressure drive hp pump is the best I've found for going beyond 60psi.

Fella, get some winter gravel tyres at about £15 a go, you'll save money, the planet and your sanity!

Thanks.. Those single barrel Lezyne 160psi pumps look similar to my mates pump.
Tire is perfect, just low on tread. 40 ℃+ days tend to boost pressure, merely 30 ℃ today yet just wrote to.....
Inflate to below Max pressure before ride;)

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Boatsie | 6 years ago
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Here we go again. Been a long time since I'd ridden a lot. Just getting spinning again.
Another blow out. Realization. Front tire is Max 120psi. Loves rolling at 100psi. Never a problem.
Rear is a gravel tire. No longer manufactured according to my recon. Brilliant tire. Max 100psi. I keep pumping tires to 100psi. I'm wrong. Hot tires. Pressure increases. Plus old worn doesn't help inner smoothness.
Rub some Fuch on them fulcrums, Muk Off per fulcrum arrays(chains) and just keep pedalling. Doh

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Boatsie | 6 years ago
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That's my mates pump. 160psi rated.

Tyres are perfect, rare is puncture. I would like to try gatorskins yet sticking with refuse because as far as I know the refuse is Aussie made; I could be wrong, often am.
Minipump working ok just ignorance from long interval between puncture had me under inflating tyre rather than sit down and pump 4 minutes.

Mates pump is in picture. Doesn't harden and canisters about twice the volume of my mini pump.

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davel | 6 years ago
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Meanwhile, you might want to look at tyres that are up to the job of the riding you're doing.

I don't know where you ride, and for what purpose, but if you're letting thorns and metal rods in over a few days' riding, you need something with a bit more industrial puncture protection.

The usual suspects: conti gatorskins, schwalbe marathon/durano, spesh armadillos.

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CXR94Di2 | 6 years ago
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All issues about unexplained deflation, use orange or stans sealant. No need to worry if you run tubeless, inner tubes or tubular tyres  1

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sergius | 6 years ago
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It takes upwards of 140 strokes on my mini-pump to get to about 60PSI on my 25mm tyres.  I can never be bothered to go beyond that - just top it off properly when you get home.

 

Different tools for different situations... I don't use CO2 as I refuse to be stuck at the side of the road having gone through all my canisters - all it takes is a duff spare tube for example (as has happened to me).

A mini-pump never runs out, yes you can't get the pressures as high as a track pump or a canister - but the increased reliability of the solution makes it a winner for me.

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Boatsie replied to sergius | 6 years ago
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sergius wrote:

A mini-pump never runs out, yes you can't get the pressures as high as a track pump or a canister - but the increased reliability of the solution makes it a winner for me.

Totally agree.. My mate was saying yesterday regarding his mini pump. He's achieving 100psi roadside. Not much effort, merely duration. I bought some co2 from eBay at $1 a bottle with free in flat or and hopefully they are just luggage. Yet coming in under the weight of a chocolate bar to carry 2, I don't mind the thought that I'll soon have extra security against praising the bicycle on the side of the road using humming bird technique. Lol.
Wondering if the warmth from the pump barrel will defrost winter hands.

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Beecho replied to Boatsie | 6 years ago
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[/quote] Totally agree.. My mate was saying yesterday regarding his mini pump. He's achieving 100psi roadside. Not much effort, merely duration. [/quote]

Would you be so kind as to tell us what pump he uses. Muchas Gratias.

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Boatsie replied to Beecho | 6 years ago
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Beecho wrote:

 

Totally agree.. My mate was saying yesterday regarding his mini pump. He's achieving 100psi roadside. Not much effort, merely duration. [/quote]

Would you be so kind as to tell us what pump he uses. Muchas Gratias.

[/quote]

It's a full length minipump, only presta valve, doesn't get hard to pump when pressure high.
Giro, Gyro, .... Not sure exactly name.. Lucky pump grabbed it at $30 from a stock run out bargain bin. Will post photo when I see him next. I know he likes to inflate very high pressure because he's blown the side walls apart from 2 new maxxis refuse 28c tires.
Cost of tires will get him down nearer 100psi sooner than pedantic explanations of rolling resistance  3
Nice pump though, I can't find them on internet to send info regarding such. Will post pic this weekend.

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Boatsie | 6 years ago
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I feel like a retard aye.
Thanks much with the advice.
Rim tape, yes. . Is on the agenda to replace. Is lumpy.
Due to the slits (explosion) I'm pretty sure it's as iandusud mentioned. Bead pinching.
I took my time last tube. Inserted. Slightly inflated. Pushed valve stem up, cleared bead near valve stem. Pulled valve stem down and screwed into rim hand fastened. Inflated more. Walked fingers around rim such that tube nested up in the tire away from the bead. Then took a couple of minutes pumping.
I was wrong about pump, works easy and perfect. Just small volume each stroke.
From no punctures to four in a row woke me up a little bit.
Cheers per co2 advice. I wanted to avoid such yet knowing the cold will soon be here I ain't wanting to grasp a small pump and feel my legs cool down.
I still feel like an idiot.. Hoping a puncture free remainder of year.  1

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iandusud | 6 years ago
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When you fit your tube make sure you have some air in it so that it sits inside the tyre before you push the bead of the tyre over the rim. If not what happens is that you risk trapping a bit of the tube under the bead of the tyre. Then when you pump it up it air will slowly creap under the bead into the trapped section of tube and it will explode with a mighty bang. I ran a bike shop for many years and this was a regular occurance on new bikes. The tyres would be inflated at the factory but not to high pressure. We would prepare a bike, including pumping up the tyres properly, and put it on display. Anything from a few minutes up to a few hours later there would be an almighty bang like a gunshot. Any poor customer nearby would get the fright of their life!

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hawkinspeter | 6 years ago
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You might have an issue with your rim tape. It's the tape that goes around the rim and protects the inner tube from the spokes/nipples/holes. It's quite easy to move it or damage it when fitting a tyre and that can cause a sudden puncture if the inner tube is pressing against a sharp bit of the rim. Check the tape and if necessary, move it to cover any spokes/holes and try again.

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StraelGuy | 6 years ago
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CO2 is my go to. Remember CO2 seeps through rubber quite quickly so when you get home, empty the tyre and reinflate with a track pump.

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Boatsie | 6 years ago
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Another explosion.
I must be the worst tube fitter ever.
Not to worried, still about 20 spare tubes to go.
From experience, once sitted properly, should last long time..

Wondering regarding side road pumping.. Ordered co2. I guess that's pretty much the norm now.

Doh had thought regarding bedding tube. Would riding a 100 metres at 30 psi then inflating to 100psi save exploding tubes please???

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Boatsie | 6 years ago
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I'm just surprised.
While asleep the rear exploded. A morning look found a 5mm thorn that had punctured the tube and another similar metal rod embedded in the tire.
Doh. . Exploded again.
Must be 1 of them days.

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