torque that schrader valve

[spokewrench]

In 2021 I had a puncture so small that it was intermittent. The tire might hold pressure very well for a week, then go flat overnight. At one point, I thought the schrader valve must be erratic. As I read about these valves, it appeared to me that the proper torque for the core had changed. It used to be 2 inch pounds, which you could apply with your fingertips on a valve cap with a key. The recommended torque may have changed 30 or 40 years ago, when valve cores began using gaskets of a harder material than rubber.

Nowhere could I find how many inch pounds are now recommended, so I bought a Slime Valve Core Torque tool. Trying to get it to click, I turned the core so hard that I was afraid I'd tear the rubber valve stem. I stopped, grabbed the stem with pliers to keep it from twisting, and turned the tool until it clicked. I don't think it would be possible to apply so much torque with a valve cap.

To find how much torque was required to click the tool, I found a metal strap that would fit the slot in the tool. I hung a soda bottle on the end of the strap and adjusted the amount of water in the bottle until I found what was just enough weight to make it click. It was 5 inch pounds. That's only 0.42 foot pounds or 0.57 newton meters, but it feels like an awful lot to apply to a valve core.

Two months ago I replaced my new OEM front tire with a Schwalbe. A few weeks ago, it began losing air so fast that I took the wheel off to see if I could find the puncture in the tube. When I started to remove the valve core, it wasn't tight. I tightened it and added air. Now it holds pressure.

When I mounted the new tire, I'd reinstalled the valve core with a core tool, but I didn't use the torque tool and didn't turn it so hard that I needed to grab the stem with pliers. I guess I didn't tighten it enough to keep that hard, slick, modern gasket from turning in use. If I have more trouble, I'll grab the stem with pliers and use the Slime torque tool.

 

[Tars Tarkas]

It's hard for me to imagine having to crank down a valve core enough to need pliers on the valve! I've never used a torque driver on a valve core and never had a problem. Maybe I'll devise some way to test how much torque I'm putting on a core when I tighten one, just out of curiosity, but I don't see myself going out and getting a dedicated tool for torquing valve cores. I deal with a lot of tires on bikes, cars, trucks, tractors, riding lawnmowers, trailers. etc. They all have Schrader valves. Maybe if I'd had the issues you've had my attitude would be different.

I have several torque wrenches -- I believe in them for many applications, but I don't use them for everything that has threads. It never occurred to me to use one a valve core......

TT

 

[6zfshdb]

Sometimes, a bit of debris on the valve stem seat is the culprit, and not the core itself. This is especially true if you use a sealant like Slime or Stans.

I use Slime, and when I can't get a good seal using just finger torque on the core, I use one of these to clean the valve seat and core gasket. Just dampen with water or a drop of alcohol. Don't use cotton Q-tips:

Amazon.com

 

[spokewrench]

Sometimes, a bit of debris on the valve stem seat is the culprit, and not the core itself. This is especially true if you use a sealant like Slime or Stans.

I use Slime, and when I can't get a good seal using just finger torque on the core, I use one of these to clean the valve seat and core gasket. Just dampen with water or a drop of alcohol. Don't use cotton Q-tips:
]

Thanks. I think I'll buy some. I used to put Slime in inner tubes, but I decided it did no good that way. I found a sort of manual from Schrader Pacific saying any time you remove a valve core, you should use a new one. I have plenty of new ones, so maybe I should follow that rule.

 

[spokewrench]

It's hard for me to imagine having to crank down a valve core enough to need pliers on the valve! I've never used a torque driver on a valve core and never had a problem. Maybe I'll devise some way to test how much torque I'm putting on a core when I tighten one, just out of curiosity, but I don't see myself going out and getting a dedicated tool for torquing valve cores. I deal with a lot of tires on bikes, cars, trucks, tractors, riding lawnmowers, trailers. etc. They all have Schrader valves. Maybe if I'd had the issues you've had my attitude would be different.

I have several torque wrenches -- I believe in them for many applications, but I don't use them for everything that has threads. It never occurred to me to use one a valve core......

TT

https://schrader-pacific.com/wp-content/uploads/Valve-Cores.pdf

I finally found the recommended torque in print. Page 6. 3 - 5 inch pounds.

Page 7 shows a Schrader torque tool. I think my Slime tool is the same thing under a different brand.

I've almost never used a torque wrench for tightening fasteners, but sometimes I've measured breakaway torque to see if I'd torqued correctly by feel. Page 7 says this doesn't work with valve cores. I agree. I can torque one to spec, and I can remove it much more easily. I guess that's why they want it torqued so tightly. (On the other hand, I have encountered stuck cores.)

About 1893, Schrader designed a sealing valve cap. If I was losing air and it wasn't a puncture, I guess my valve core and my cap both leaked.

 

[Gionnirocket]

Sometimes, a bit of debris on the valve stem seat is the culprit, and not the core itself. This is especially true if you use a sealant like Slime or Stans.

I use Slime, and when I can't get a good seal using just finger torque on the core, I use one of these to clean the valve seat and core gasket. Just dampen with water or a drop of alcohol. Don't use cotton Q-tips:

Amazon.com

I've used Q_tips for years without issue. The trick is to get it wet and twist it tight in one direction. Then when cleaning the core only turn in that same one direction.
I've also used the valve core remover that has the tap for the stem on it and ran it in a few times with a few drops of water.
Sorry but I find it a little ridiculous to spend $10 and have a separate item just to clean a valve core. If you have another use for them... Then maybe

As for torque_ing it to spec

 

[spokewrench]

As for torque_ing it to spec

Several times in the last 3 years, I have found cores that weren't as tight as I remembered installing them.

 

[Gionnirocket]

Several times in the last 3 years, I have found cores that weren't as tight as I remembered installing them.

I've never had an issue... and the number of cores removed/installed are countless.

Perhaps get yourself a box of..



edit:
Just to give it some perspective.
My brother and nephew are auto mechanics with a high end clientele. My nephew has every tool imaginable, certifications up the wazoo and knows specs like Mona Lisa Vito

I've watched him install many a valve core and a torque wrench was never in sight... just sayiń

 

[spokewrench]

My brother and nephew are auto mechanics with a high end clientele. My nephew has every tool imaginable, certifications up the wazoo and knows specs like Mona Lisa Vito

I've watched him install many a valve core and a torque wrench was never in sight... just sayiń

Do they make house calls? I thought luxury auto clientele simply phoned their dealer.

If your nephew is in the habit of having you watch how he installs valve cores, I guess he's trying to teach you the basics. If you'd asked why he doesn't use a valve core torque wrench, I'm sure he would have told you, as would I, that there's no such thing. Unless he uses a favorite valve cap to screw them in, his core tool may well be a torque core tool.

https://www.amazon.com/VOTNMIC-Pieces-Removal-Installation-%EF%BC%88Black%EF%BC%89/dp/B0CG2FWLV1

I used to undertighten because using a valve cap, the proper torque would have caused tremendous sheer on my skin, on such a short radius and small area. I still tend to undertighten for two reasons. I came up when cores were designed for 2 inch pounds, and stems on bicycle tubes twist pretty easily. (I think car valves can be stouter because car rims use weights for balance.)

For auto mechanics who came along since core seals changed, maybe 1980, it may feel perfectly natural to apply adequate torque. In fact, the big reason many professionals use torque core tools seems to be that otherwise they may damage TPMS by turning much harder than 5 inch pounds.

 

[Gionnirocket]

Yeah... Ok
If you haven't picked up on it yet, you seem to be the only one (perhaps on the planet) struggling with this.

 

[spokewrench]

Yeah... Ok
If you haven't picked up on it yet, you seem to be the only one (perhaps on the planet) struggling with this.

I'll bet the nephew who taught you everything you know about valve cores told you that, and it makes my day. Call me Mr. Humble, but I'd never imagined he'd heard of me.

I dialed the TRA to report what I'd learned so they would stop publishing specs that nobody else on the planet cares about. As the line rang, I realized that the receptionist was sure to ask if I had any high-end clientele, and when I said no, she'd put me on perpetual hold. I hung up before she got the chance.

I wonder if you would do everybody else on the planet a favor and have your nephew set the TRA straight. When a gentleman with high-end clientele speaks, people listen.

 

[Gionnirocket]

You're right that she put you on hold.... But the reason was she pee'd herself when she heard an adult was struggling with a valve core. Several times over years no less. Then she just kept replaying the call for her coworkers as they laughed their ass's off and no one could stop laughing long enough to pick up the line again.
You must be a lot of fun around the house when someone doesn't torque down the top to the pickle jar correctly.

ps... I was too embarrassed to even mention your struggle to my nephew.

A spokewrench is definitely my new favorite tool

 

[Rome]

For you my friend I suggest switching over to Presta valves. It's smaller hole and has a tiny nut you can twist with your fingers even with gloves on to seal the valve.
Replacement Presta valve stem is cheap. I have gold plated ones with military grade o ring seal.

 

[spokewrench]

For you my friend I suggest switching over to Presta valves. It's smaller hole and has a tiny nut you can twist with your fingers even with gloves on to seal the valve.
Replacement Presta valve stem is cheap. I have gold plated ones with military grade o ring seal.

Thanks. As a presta newby, I'd probably find complications, such as finding presta inner tubes in my sizes and having cores shoot like bullets when loosened wrong. I might find that I'd need to change to rims with smaller holes, and where would I find them?

For 70 years of working with Schraders on bikes, motorcycles, cars, trucks, mowers, and farm equipment, the only problem I recall was that sometimes a missing cap would let a core corrode and seize. A box wrench would break it loose, and even then, rubber stems didn't twist much. I guess those stems were stouter than the ones on bicycles.

I used to put caps with key tops on Schraders so I wouldn't have to fetch a core tool to remove a core. Call me blissfully ignorant, but I thought finger torque was plenty. Three years ago, I began checking cores every time I found I'd lost a little air because I wrongly suspected them. It surprised me that they often needed tightening, but it wasn't until the other day that I could be sure that a loose core was the cause of air loss.

I've finally learned why finger torque is no longer reliable. A Schrader core has an inner seal and an outer seal. Both used to be rubber. Decades ago, they began using teflon for the outer seal. For a bolt with a rubber washer, finger tight may be plenty. If you switch to a teflon washer, you may have to tighten it more so that thread friction will keep it from unscrewing.

 

[Gionnirocket]

If this has been a multi year struggle after a lifetime of experience with a Schrader....
Forget about a Presta, it'll be a Rubik's Cube

 

[Tars Tarkas]

I'll say this for what it's worth. I set my little Park Tool inch pound driver to 4 in lbs and cranked it in a vise until it clicked. I don't think I ever use that much torque on a Schrader valve core. I don't think I ever will. Four is as low as that driver goes, so I didn't get to try what 2 or 3 inch pounds feels like, but I'm guessing I'm somewhere in that range. Again, I've never had a problem.

If I were a paid mechanic setting valves on a high end car with TPMS I can see that measuring torque would probably be a good idea -- maybe even required by manufacturers for warranty coverage. I'm still not buying a dedicated torque driver for my bikes -- or anything else. As Gionni says, a little differently, this has been much ado about nothing.

TT

 

[Tars Tarkas]

Well, this is embarrassing. My Park Tool torque driver measures Newton meters, not inch pounds. So when it's set on 4, that's about 35 inch pounds, so hell no, of course I don't crank valve cores down that much.

When I was trying this in the vise, I was thinking, would I need a pair of pliers to hold the valve in place if I was setting a valve core this tight. Yeah, maybe. Which makes me wonder if SW is cranking his valve cores down to 4 newton meters, not inch pounds.

It's been a while since I've used this Park driver. Maybe I can be forgiven for thinking it was set for inch pounds.

TT

 

[Gionnirocket]

This is an an example of a simple lack of common sense.
For most anything a printed torque value can be found. Not saying that they should be ignored but experience and common sense make precise measurements of the simplest of tasks unnecessary. First time something leaks and then found loose I would instinctively tightened a little more the second time around. The Schrader core installing world seems to have solved this issue on its own without much ado.
Here's another ebike example that I (and I belive the rest of the torque'ng world) just wing without issue.


Now some TPMS may require a little bit more care, attention and perhaps be measured... but it's totally irrelevant when speaking about bicycle Schrader valves and the idea that one needs to do the same is just ridiculous.
I'm due for an annual inspection so I'll ask my nephew when and if it's necessary on some of the more exotic hardware.

Maybe practice applying maximum allowable torque'g?
Here's an instructional video that may help.

 

[spokewrench]

When I was trying this in the vise, I was thinking, would I need a pair of pliers to hold the valve in place if I was setting a valve core this tight. Yeah, maybe. Which makes me wonder if SW is cranking his valve cores down to 4 newton meters, not inch pounds.

I see you reacted to my first post without reading it. I said I used a proper core tool, then measured to see how it was calibrated. I said I found 5 inch pounds. I said that was equivalent to 0.57 newton meters.

When I began checking valve cores and kept finding ones that needed tightening, I started using a 4-in-one tool to get them tighter. It didn't work very well between spokes, so I ordered screwdriver-type core tools. I cut one down to fit between a 20 inch rim and the hub.

I can torque a fastener by feeling the elasticity as I stretch or compress it. That doesn't work on teflon seals. I got a torque tool because I didn't know what was recommended, and the tool would give me consistency. It's currently $5.52. I gladly paid more.

 

[Tars Tarkas]

I see you reacted to my first post without reading it. .

Without going back and rereading it. It's been so long ago....

This all seems to boil down to you get good results with a torque driver and other people get good results without one. Guessing, most people, by far, manage quite well without the tool.

TT