Schraeder "valve creep"
All of my bikes have presta valves, in many cases with those tubular aluminum adapters that allow the presta stem to fit snugly in a rim drilled for schraeder stems.
I'm now building up a touring bike for a friend. It has those indestructible Araya rims that came on so many Japanese bikes from the 80s. They're drilled for schraeder stems, and I'm thinking that I might just install schraeder tubes, since I have a bunch of them that I ordered by mistake a year ago. Here's the question, though: How does one prevent schrader tubes from creeping around the rim so that after a few months the valve stem is pointed off at a crazy angle, rather than right at the hub? That's one of the things that bothers me about schraeder valves (another is that the stems get packed full of mud if you lose the valve cap). Is there a simple solution to that issue (preventing valve creep, not keeping mud out of the valve stem)? EDIT: Note that this is not a general question about the relative advantages and disadvantages of presta and schraeder valves. That dead horse has been well beaten. Just looking for a solution to the valve-creep problem. And yes, I know that it's a bigger problem at low pressures. |
Maybe that might be from riding with the tires under - inflated (?)
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Originally Posted by Bianchi84
(Post 21349376)
Maybe that might be from riding with the tires under - inflated (?)
The rims in question have straight walls, so tire pressure is limited to about 75psi. Which happens to be the tire pressure I prefer even with hook-beaded rims. |
Obviously you have ample torque.
:) |
?
Originally Posted by repechage
(Post 21349425)
Obviously you have ample torque.
:) Or was he the bass player? Yeah, pretty sure he played bass. |
if valve creep is from under inflation you’ll have to address that somehow. if the bike isn’t for you then maybe you can move past your personal preference for 75 psi & let the owner go up to 80 or 90 psi. also doesn’t it depend on compliance &maintenance? meaning check pressure regularly & not waiting for it to “look” low. when I was a kid i never used a gauge just squeezed them & filled them when they looked low. Then tilted valves were common. We use shrader valves on all 6 family bikes & never have tube creek or tilted valves & my Wife & Daughter both prefer less pressure than Son & I. the bikes only get ridden after the psi have been checked
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Originally Posted by jonwvara
(Post 21349438)
Wait, wasn't Ample Torque the drummer for The Monkees?
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Originally Posted by rumrunn6
(Post 21349440)
Get diff rims that are hooked?
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Originally Posted by jonwvara
(Post 21349458)
That would work! But riding higher-pressure tires isn't a solution to my existing problem--it's a new problem
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Nowadays, I wont use any Schrader-valved tubes that do not have a threaded stem. Conti and Schwalbe are my go-to's. I also use metal caps, and if there is any doubt about them coming off, I coat the stem threads with beeswax. FWIW, its a rarity (now) that I use anything but Presta... and this is not a debate over Presta vs Schrader - just a personal preference.
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3M black weatherstrip adhesive. :)
hooked rims increase the contact area besides providing a mechanical hook. i have not looked for tires for straight sided rims for decades - I do have one bike with them, will be switching it to hooked rims soon just to have more tire choice |
Schrader valves never creep on my bikes, and I only run those tires in the 30-40 psi range. Guess I must be a wimp. :(
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I only have valves creep when I run super low pressures.
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Originally Posted by ThermionicScott
(Post 21349627)
Schrader valves never creep on my bikes, and I only run those tires in the 30-40 psi range. Guess I must be a wimp. :(
Do others find that valve creep is a non-issue even at moderately low pressures? |
Originally Posted by jonwvara
(Post 21349766)
Do others find that valve creep is a non-issue even at moderately low pressures? |
Originally Posted by jonwvara
(Post 21349766)
I have seen plenty of schraeder wheels with crazily-angled valve stems but since I haven never used said wheels myself, I have no idea how they got that way.
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Originally Posted by jonwvara
(Post 21349766)
Maybe I'm trying to solve a nonexistent problem. I have seen plenty of schraeder wheels with crazily-angled valve stems but since I haven never used said wheels myself, I have no idea how they got that way. Maybe it only happens if wheels are run while nearly flat? If they can be run at 30-40psi without problems, I guess I have been wasting everyone's time. If I'd thought this through I'd have realized that lots of mountain bikes use schraeder valves and are run at pretty low pressures, but I don't hear a lot of mountain bikers complaining about their valve stems?
I'm probably a little more OCD than most, in that I'll tug the uninflated tire one way or the other to get that valve straight again, and will unmount everything and start again if that's what it takes. :) Tire creep *does* happen, but like you say, it takes really super-low pressures that we shouldn't be running on the road and when touring. Just begging for a pinch flat at that point. :thumb: |
21 psi front / 25 psi rear no valve creep ...
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Originally Posted by jonwvara
(Post 21349766)
Do others find that valve creep is a non-issue even at moderately low pressures?
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Originally Posted by madpogue
(Post 21349862)
In all likelihood, they started out that way, installed and inflated by Target/Walmart or high-volume LBS employess who don't care, or just don't know.
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It might be some tires are more prone to this than others. Try a different brand maybe?
A slight aside... You don't necessarily need hook edge rims to run 90 psi, though it is safer. Bikes were pumped up to 90 as more or less standard pressure during the 27 x 1 1/4" era, often with straight wall Weinmann concaves or Super Champion Mod 58's. Pretty much all tires had wire beads though, until the 'Turbo' came out. But that was then and this is now. I mention this only for historical value. I think most modern tires are made assuming they will go on a hooked rim, so a fair amount of caution should be used if pumping to higher pressures. Likely some tires will hold fine, and others will pop off with a loud bang... |
My rear Schrader valves creep a little. I usually run 35 to 45 lbs. Its no biggie to me.
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Originally Posted by rumrunn6
(Post 21349930)
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Inner tubes will often attach to the tyre inner case from heat build-up or patch glue. If the tyre creeps, so too will the inner tube and valve. This can be mitigated by applying talc to the tube before installation. If you soap the tyre and/or rim to facilitate installation, it is more likely to creep, especially if ridden immediately, before the soap can dry out.
Rims and tyres have varying susceptibility to creep. Hooked edge aluminum rims are the least prone, while steel is the most likely to creep. Tyre design in area bead seat area can affect creep, which also increases with older, harder tyres. I've seen a few cases where misaligned rim tape was the root cause of valve stem canting. However, as stated the biggest factor is proper alignment prior to inflation. If it's not straight, you can't just straighten the stem. You have to rotate the tyre slightly to realign the tube and straighten the stem. |
I think that repechage and Salamandrine have somewhat keyed in on the actual problem, which I have known to occur at proper road bike air pressures.
I'll first get out of the way the possibility that the Araya rims may be relatively slippery along their extruded and anodized tire-gripping surfaces. But what I have concluded without any doubt is that certain tires, usually those having aged/dry/dirty rim-contact surfaces, are mightily prone to slipping along the rim! And even blowing off the rim in the case of the narrow old Araya double-walled rims. I have applied rim cement along certain old tire's bead-seating area to mitigate this, but I can't really recommend this. It did help though. Don't get me started on tubular valve stem creep, I have too many stories... |
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