Advertise on Bikeforums.net



User Tag List

Results 1 to 25 of 25
  1. #1
    Senior Member
    Join Date
    May 2005
    Location
    Ventura, CA
    My Bikes
    Dean, De Rosa, Langster, some old Brit track iron
    Posts
    424
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Tire pressure whips my butt.

    I rode my usual 30 miles yesterday and the ride seemed unusually rough. It's a beat up road to begin with but I was just getting rattled and fatigued, so I thought I was just tired. The next day I took the SS off the rack for a change of pace and for some reason, I decided to check the pressure coming off the scuba tank I use to inflate tires. 150 psi! O-k-a-a-a-y. Krylion carbons ride like Flintstone wheels at 150 in case anyone is interested.

  2. #2
    Senior Member Catweazle's Avatar
    Join Date
    Mar 2008
    Location
    Sale, Victoria, Australia
    Posts
    663
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    At that pressure a blowout would make an AWESOME noise!




  3. #3
    Life is good RonH's Avatar
    Join Date
    Jan 2001
    Location
    Between Lecanto and Hernando Florida, 6 miles west of the Withlacoochee Trail
    My Bikes
    I've had several since 1999 but have settled on my beloved 2001 Litespeed Tuscany and my latest, a 2013 Cannondale CAAD 10.
    Posts
    13,539
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by neilG View Post
    ... I decided to check the pressure coming off the scuba tank I use to inflate tires.
    Why not use a floor pump like most people?
    My bikes --> 2001 Litespeed Tuscany---2013 Cannondale CAAD 10 2 (5) "Racing Edition"

    Life is like a 10-speed bicycle. Most of us have gears we never use. ~ Charles Schultz

  4. #4
    just keep riding BluesDawg's Avatar
    Join Date
    Feb 2005
    Location
    Milledgeville, Georgia
    My Bikes
    2014 Specialized Crave Pro 29, 2014 Specialized Crux EVO Carbon Disc, 2012 Black Mountain Cycles Monster Cross, 2011 Specialized Roubaix SL3 Expert Compact, 2009 Salsa Casseroll, 2003 KHS Milano Tandem, 1986 Nishiki Cadence rigid MTB
    Posts
    12,713
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by RonH View Post
    Why not use a floor pump like most people?
    +1
    The more you ride your bike, the less your ass will hurt.

  5. #5
    Small Member maddmaxx's Avatar
    Join Date
    Nov 2003
    My Bikes
    Leader home built hardtail, Diamondback Response
    Posts
    7,071
    Mentioned
    4 Post(s)
    Tagged
    1 Thread(s)
    I have read cautions about using service station air compressors, especially on road tires because they can deliver so much pressure at large volumns of air as to be dangerous to bicycles.

    At 150psi, you are exceeding the rating on some rims..............be sure you know what yours are. After allowing for pressure build up due to heat on downhill brake applications you could be way up there. HED, makers of pro racing carbon wheels have lowered their max pressure ratings lately (to 128psi I believe)after research showed 300/400degf temperatures on TDF style downhills resulting in 25+ lb pressure increases over the static put into the tire.

  6. #6
    Senior Member
    Join Date
    May 2005
    Location
    Ventura, CA
    My Bikes
    Dean, De Rosa, Langster, some old Brit track iron
    Posts
    424
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by RonH View Post
    Why not use a floor pump like most people?
    That's too much like work.

  7. #7
    Senior Member Retro Grouch's Avatar
    Join Date
    Feb 2004
    Location
    St Peters, Missouri
    My Bikes
    Rans Enduro Sport, Hase Kettweisel Tandem, Merin Bear Valley beater bike
    Posts
    23,604
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by maddmaxx View Post
    I have read cautions about using service station air compressors, especially on road tires because they can deliver so much pressure at large volumns of air as to be dangerous to bicycles.
    40 years ago using service station air compressors might have been a problem. I don't think it's much of an issue today.

    40 years ago bikes had and 75 psi tires and rims that didn't have hook beads.

    Also 40 years ago service stations did service and had big air compressors to operate the service lift. The compressors they have today are wimpy by comparison. I doubt a modern gas station air compressor will inflate a 110psi road bike tire.

  8. #8
    Senior Member
    Join Date
    May 2005
    Location
    Ventura, CA
    My Bikes
    Dean, De Rosa, Langster, some old Brit track iron
    Posts
    424
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by maddmaxx View Post
    I have read cautions about using service station air compressors, especially on road tires because they can deliver so much pressure at large volumes of air as to be dangerous to bicycles.
    That's only because the pressure of the gas station compressor may be higher than most bike tires. You can't "over-volume" a tire, but you CAN over-pressurize it. As soon as the pressure of the tire equalizes with the compressor, it can't fill any more. The same with the scuba regulator/inflator: the regulator is set to a specific pressure and filling stops when the tire pressure is equal with that. In my case, because of some wear and tear on the admittedly ancient scuba regulator, the pressure crept up too high.

    Oops, while I was typing, Retro got it.

  9. #9
    Senior Member Catweazle's Avatar
    Join Date
    Mar 2008
    Location
    Sale, Victoria, Australia
    Posts
    663
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Most service station compressors nowadays have digital presets which only allow tyres to be inflated to about 60 psi. They won't inflate to a higher pressure than that. That's hardly adequate for riding, and even if you cop an 'over-pressure' boost by using it on a low volume bike tyre I'd think it's not likely to be a problem. You'd still end up with a tyre which is only inflated far enough to ride uncomfortably home on!

  10. #10
    just keep riding BluesDawg's Avatar
    Join Date
    Feb 2005
    Location
    Milledgeville, Georgia
    My Bikes
    2014 Specialized Crave Pro 29, 2014 Specialized Crux EVO Carbon Disc, 2012 Black Mountain Cycles Monster Cross, 2011 Specialized Roubaix SL3 Expert Compact, 2009 Salsa Casseroll, 2003 KHS Milano Tandem, 1986 Nishiki Cadence rigid MTB
    Posts
    12,713
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Your bike is very embarrassed. If not for self respect, do it for the bike. Get a pump...or a Huffy.
    The more you ride your bike, the less your ass will hurt.

  11. #11
    Senior Member BCRider's Avatar
    Join Date
    Mar 2008
    Location
    The 'Wack, BC, Canada
    My Bikes
    Norco (2), Miyata, Canondale, Soma, Redline
    Posts
    5,410
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    I run my scuba tanks as an air source for the shop too. Are you using just a first stage or is there a secondary reg as well?

    Standard interstage pressure for scuba regs is 150 psi. As in that's what the first stage outputs. If you ended up with that much in your tire your second stage reg may be faulty and it's letting through the entire first stage output.

    And before I get raked over the coals like you are I just want to FIRMLY mention that I DO use a floor pump for my bicycles.....
    Model airplanes are cool too!.....

  12. #12
    Philologist
    Join Date
    Jun 2008
    Location
    Birmingham, Alabama
    My Bikes
    Univega Gran Turismo
    Posts
    437
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Retro Grouch View Post
    40 years ago using service station air compressors might have been a problem. I don't think it's much of an issue today.

    40 years ago bikes had and 75 psi tires and rims that didn't have hook beads.

    Also 40 years ago service stations did service and had big air compressors to operate the service lift. The compressors they have today are wimpy by comparison. I doubt a modern gas station air compressor will inflate a 110psi road bike tire.
    40 years ago I almost always used service station air compressors for my bike tires. I had a floor pump, but didn't like all the effort it took to use it, so I'd pump up a low tire just enough to ride on it, then ride to the service station to top it off. That's how I did it for about twenty years and never had a problem. The trick was to give it very short bursts of air from the compressor tank and check with a tire gauge after every burst.
    s ofereode, isses swa mg. ("That passed away, this also can.")
    from Deor, in the Exeter Book (folios 100r-100v)

  13. #13
    Senior Member
    Join Date
    May 2005
    Location
    Ventura, CA
    My Bikes
    Dean, De Rosa, Langster, some old Brit track iron
    Posts
    424
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by BCRider View Post
    I run my scuba tanks as an air source for the shop too. Are you using just a first stage or is there a secondary reg as well?
    No, one only needs a first stage. The second stage's job is to bring pressure to ambient, so that wouldn't work.

    Standard interstage pressure for scuba regs is 150 psi. As in that's what the first stage outputs. If you ended up with that much in your tire your second stage reg may be faulty and it's letting through the entire first stage output.
    All first stages are adjustable within a range. This one is normally set to 115 but the seat must have taken a set that raised the pressure between the times I checked it. I really should attach a gauge to it. It's an ancient USD externally adjustable piston regulator.

    And before I get raked over the coals like you are I just want to FIRMLY mention that I DO use a floor pump for my bicycles.....
    You know, if these fellow old dudes want to work harder than they need to who am I to judge them?

  14. #14
    Senior Member
    Join Date
    May 2005
    Location
    Ventura, CA
    My Bikes
    Dean, De Rosa, Langster, some old Brit track iron
    Posts
    424
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by BluesDawg View Post
    Your bike is very embarrassed. If not for self respect, do it for the bike. Get a pump...or a Huffy.
    My bike is not embarrassed, it's a very high class machine sharing garage space with some very high zoot scuba gear. They enjoy their time together.

  15. #15
    Bicycle Repair Man !!! Sixty Fiver's Avatar
    Join Date
    Sep 2007
    Location
    YEG
    My Bikes
    See my sig...
    Posts
    25,773
    Mentioned
    13 Post(s)
    Tagged
    2 Thread(s)
    My local station has a pump that is only good for 85psi... it works for the mtb and older bikes but the 120 psi tyres need a hands on (pump) approach if I am not at my (bike) shop.

  16. #16
    Small Member maddmaxx's Avatar
    Join Date
    Nov 2003
    My Bikes
    Leader home built hardtail, Diamondback Response
    Posts
    7,071
    Mentioned
    4 Post(s)
    Tagged
    1 Thread(s)
    Sorry, perhaps I used a wrong turn of phrase when I said that some compressors have to much "volumn". What I actually ment was they have the "capacity" (because of the volumn of air they are capable of delivering) to arrive at the desired pressure too quickly. Even tires with hook beeds do not always seat correctly and it is quite possible with a large compressor to damage stuff before you know it.

  17. #17
    Senior Member
    Join Date
    Feb 2007
    Location
    S.E. Pennsylvania, USA
    Posts
    1,737
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by neilG View Post
    I rode my usual 30 miles yesterday and the ride seemed unusually rough. It's a beat up road to begin with but I was just getting rattled and fatigued, so I thought I was just tired. The next day I took the SS off the rack for a change of pace and for some reason, I decided to check the pressure coming off the scuba tank I use to inflate tires. 150 psi! O-k-a-a-a-y. Krylion carbons ride like Flintstone wheels at 150 in case anyone is interested.
    I don't especially like the way the Kryilon's ride even at the correct pressure. I thought they were a bit too stiff. I can't imagine them at 150 PSI.
    Oh I used to be disgusted and now I try to be amused. But since their wings have got rusted, you know, the angels wanna wear my red shoes. But when they told me 'bout their side of the bargain, that's when I knew that I could not refuse. And I won't get any older, now the angels wanna wear my red shoes.

  18. #18
    feros ferio John E's Avatar
    Join Date
    Jul 2000
    Location
    www.ci.encinitas.ca.us
    My Bikes
    1959 Capo; 1980 Peugeot PKN-10; 1981 Bianchi; 1988 Schwinn KOM-10;
    Posts
    14,674
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    These days many cyclists seem to go for overinflation. I find that something like 90 PSI front, 95 rear gives 28mm tires a comfortable, yet efficient, ride. (I weigh about 150 lbs; your situation may vary.)
    "Early to bed, early to rise. Work like hell, and advertise." -- George Stahlman
    Capo [dschaw'-poe]: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger, S/N 42624
    Peugeot: 1970 UO-8, S/N 0010468
    Bianchi: 1981 Campione d'Italia, S/N 1.M9914
    Schwinn: 1988 Project KOM-10, S/N F804069

  19. #19
    just keep riding BluesDawg's Avatar
    Join Date
    Feb 2005
    Location
    Milledgeville, Georgia
    My Bikes
    2014 Specialized Crave Pro 29, 2014 Specialized Crux EVO Carbon Disc, 2012 Black Mountain Cycles Monster Cross, 2011 Specialized Roubaix SL3 Expert Compact, 2009 Salsa Casseroll, 2003 KHS Milano Tandem, 1986 Nishiki Cadence rigid MTB
    Posts
    12,713
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by neilG View Post
    My bike is not embarrassed, it's a very high class machine sharing garage space with some very high zoot scuba gear. They enjoy their time together.
    No problem. Whatever makes you happy.

    Part of my enjoyment of cycling comes from using equipment specifically designed for cycling. Other stuff may work, but it doesn't seem right. I like a bit of adherence to tradition. It just feels right to me.
    The more you ride your bike, the less your ass will hurt.

  20. #20
    Life is good RonH's Avatar
    Join Date
    Jan 2001
    Location
    Between Lecanto and Hernando Florida, 6 miles west of the Withlacoochee Trail
    My Bikes
    I've had several since 1999 but have settled on my beloved 2001 Litespeed Tuscany and my latest, a 2013 Cannondale CAAD 10.
    Posts
    13,539
    Mentioned
    3 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by neilG View Post
    That's too much like work.
    And riding hard or climbing a hill isn't?
    My bikes --> 2001 Litespeed Tuscany---2013 Cannondale CAAD 10 2 (5) "Racing Edition"

    Life is like a 10-speed bicycle. Most of us have gears we never use. ~ Charles Schultz

  21. #21
    Gilpin County Wheelman SKYLAB's Avatar
    Join Date
    Apr 2008
    Location
    Rollinsville Colorado
    My Bikes
    Parlee Z-4 2001 Fisher Sugar 1 Macalu Ti
    Posts
    814
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    dude - a joe blow costs about 30 bucks. I always check tire pressure before every ride. Takes perhaps 45 seconds.
    Of course - do what you want but don't expect sympathy when those tires blow off your rims. Or you get a pinch flat at 30 mph on a down hill.
    And you know that notion just crossed my mind.

  22. #22
    Senior Member BCRider's Avatar
    Join Date
    Mar 2008
    Location
    The 'Wack, BC, Canada
    My Bikes
    Norco (2), Miyata, Canondale, Soma, Redline
    Posts
    5,410
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by neilG View Post
    No, one only needs a first stage. The second stage's job is to bring pressure to ambient, so that wouldn't work.


    All first stages are adjustable within a range. This one is normally set to 115 but the seat must have taken a set that raised the pressure between the times I checked it. I really should attach a gauge to it. It's an ancient USD externally adjustable piston regulator.


    You know, if these fellow old dudes want to work harder than they need to who am I to judge them?
    Sorry, I wasn't suggesting the regular scuba second stage. Instead I was asking about something like a paint spraying second stage you add instead of the mouthpiece one. I'm using such a rig on my setup to bring the line pressure down to from 5 to 120 for using it with airbrushes, small spray guns, air nozzles and even the one time when I maxed it to 120 so we could use an air impact ***. Normally it sits at around 25 for the air nozzle but gets bumped to 40 often for the bigger motorcycle tires

    True on the settable nature. And a guage would be a good idea. I'd also suggest a burst disc on your output that will let go before the bursting pressure of the supply hose. In my case the second reg has an over pressure relief that is internally set to about 20 to 25 psi over the set pressure so it serves the purpose nicely. But if the tank reg leaks with no way to vent the excess and the supply line tries to reach 3000 psi at some point you'll have lots of rubber flying around the shop at a high rate of knots!

    And if you can stand the ridicule of this lot over using your tanks I guess I can too. I'm off to fill a bicycle tire from my scuba tanks just to spite them....
    Model airplanes are cool too!.....

  23. #23
    Senior Member guybierhaus's Avatar
    Join Date
    Sep 2005
    Location
    Oley, PA
    My Bikes
    Flat bar road bike, trail bike and MTB
    Posts
    878
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    In the olde days when I worked at a service station, that actually had service, the one and only big compressor was set at 150psi. Best for lift, impact wrench and what I called a zap ***, aka air chisel for cutting off exhaust pipes. Now we have filling stations with small little compressors. Some require a quarter to run. Either way don't believe they will pump more then 50 psi. What I haven't heard is all these compressors are fitted for schrader valves, but as I write this I do remember getting a small presta to schrader adapter. I'll have to find that thing, I'd prefer to use a compressor my self. Think my little compressor is limited to 100 psi.
    BierHaus Bertolette Road Bike, built 2007
    BierHaus SRT Trail Bike, built 2010
    Fuji Mt. Pro - 2007

  24. #24
    Senior Member Velo Fellow's Avatar
    Join Date
    Apr 2008
    Posts
    344
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    "You just put your lips together and.....blow." But it helps if you have Lauren Bacall doing the blowing.

  25. #25
    Senior Member
    Join Date
    May 2005
    Location
    Ventura, CA
    My Bikes
    Dean, De Rosa, Langster, some old Brit track iron
    Posts
    424
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by SKYLAB View Post
    dude - a joe blow costs about 30 bucks. I always check tire pressure before every ride. Takes perhaps 45 seconds.
    Of course - do what you want but don't expect sympathy when those tires blow off your rims. Or you get a pinch flat at 30 mph on a down hill.
    dude, an air fill costs $4 and I can fill my tires for months, takes about 3 seconds.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •