Author Topic: airing up tubes/tires  (Read 1375 times)

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Offline evinrude7

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airing up tubes/tires
« on: August 21, 2019, 06:13:41 PM »
anyone else have to air up their tubes/tires once a week?  i generally have to add 4-5 lbs to both front and back.  these are fairly new tubes.  both maybe 6 months old.  don't recall the brand but they were probably $20-$25 tubes (ea.)
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Offline jgger

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Re: airing up tubes/tires
« Reply #1 on: August 21, 2019, 06:22:51 PM »
Pull the valve core and put some oil on it, nail gun type oil is good. Make sure it is snugged down when you install it, and ALWAYS run a cap on the filler stem. Or change the valve cores for new ones with a drop of oil on them. Very common for leaks there if you run with no caps and then add air, it blows crap into the core's seat.
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Offline evinrude7

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Re: airing up tubes/tires
« Reply #2 on: August 21, 2019, 06:33:05 PM »
Pull the valve core and put some oil on it, nail gun type oil is good. Make sure it is snugged down when you install it, and ALWAYS run a cap on the filler stem. Or change the valve cores for new ones with a drop of oil on them. Very common for leaks there if you run with no caps and then add air, it blows crap into the core's seat.

i always run a cap but my parking spot/garage is a dusty gravel carport on the back of the house.  i'll change out the valve cores, add some oil and see what's up.  plenty of nail gun oil here.  i shoot one daily.  thanks jgger.   
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Offline jgger

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Re: airing up tubes/tires
« Reply #3 on: August 21, 2019, 06:41:38 PM »
If that doesn't work you might have a pinched tube. When you put them in did you air up then deflate then re-inflate to remove the wrinkles?
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline evinrude7

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Re: airing up tubes/tires
« Reply #4 on: August 21, 2019, 07:32:37 PM »
If that doesn't work you might have a pinched tube. When you put them in did you air up then deflate then re-inflate to remove the wrinkles?

i did.  still could have pinched them. 
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Offline 1976cb750f836

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Re: airing up tubes/tires
« Reply #5 on: August 22, 2019, 05:26:15 AM »
I only have to air mine at the beginning of riding after winter, once last all summer if no flats. You have some sort of problem.

Offline maxheadflow

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Re: airing up tubes/tires
« Reply #6 on: August 22, 2019, 06:31:18 AM »
For me the wire spoke wheels, tube tires seem to need air about every 2 weeks.  Smaller front tires lose the most air.  On the bikes with mags I can get away with a month or 2.

Offline MauiK3

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Re: airing up tubes/tires
« Reply #7 on: August 22, 2019, 03:29:06 PM »
I often add air to my tube tires. Once a month or so.
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Offline seanbarney41

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Re: airing up tubes/tires
« Reply #8 on: August 22, 2019, 04:53:55 PM »
Everyone should be checking tire pressure at least once a week...really before every ride
If it works good, it looks good...

Offline Tracksnblades1

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Re: airing up tubes/tires
« Reply #9 on: August 22, 2019, 08:36:44 PM »
Everyone should be checking tire pressure at least once a week...really before every ride

+1

I've had good luck with new rim strips, new tubes,  and lots of baby powder during mounting.
Always inflating with no valve core, deflate completely, reinflate check tire centering, deflate completely, install core, reinflate to desired pressure.

Aluminum CR rims with dual bead locks, well, it's when, not if, with regards to pinching the tube once in a while.....😩
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Online scottly

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Re: airing up tubes/tires
« Reply #10 on: August 22, 2019, 08:56:33 PM »
If you think the valve stems are leaking, wipe some spit over the end and look for bubbles. ;)
Tubes should hold pressure for months, not just weeks.
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Offline Doobie

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Re: airing up tubes/tires
« Reply #11 on: August 23, 2019, 02:12:01 AM »
anyone else have to air up their tubes/tires once a week?

Not me for my current CB or the two I had before it. I'd guess pinched tubes.
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Offline dave500

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Re: airing up tubes/tires
« Reply #12 on: August 23, 2019, 03:58:22 AM »
ive never had tubes hold for more than coupla weeks for years?tubeless car ones seem to?bike always seems to need a few psi before a ride,i run metal caps with rubber seal inside,spit never bubbles?porous tubes for sure,just the way it is?or poor seal around the vulcanising at valve stem?

Offline MauiK3

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Re: airing up tubes/tires
« Reply #13 on: August 23, 2019, 09:20:51 AM »
Even tubeless car tires drift down, I know of a big Lexus SUV that seems to need the tires topped off within a month or so, the tire monitor is always complaining.
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Offline TwoTired

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Re: airing up tubes/tires
« Reply #14 on: August 23, 2019, 09:35:06 AM »
Rubber is a permeable membrane, meaning air can pass through it.  The rate of flow depends on thickness and rubber compound density.  Undersize tubes can stretch it thinner.

If you can soak the tire/tube/rim in soapy water and not see air bubbles, it is just passing through the membrane.

Heavy duty tubes used to be available, haven't checked recently, they were thicker.  They also weighed more, so bad for un-sprung weight/handling.  It's a trade off.

Even so, not all rubber compounds have the exact same properties.  So, your air loss could be brand specific (which you didn't report).

I've been pretty happy with the Metzeler tubes.  Air up in the spring, maybe add a lb. or two 2-3 months intervals.

One possible alternative is to slime the tubes for extra seal of the membrane.  I don't really like that idea, though, due to possible balance oddities, even if transient.

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