I have been using a presta to shrader adapter because that how my air pump is and my compressor . I am still running tubes and I have a bunch of shrader tubes and debated drilling out the rim . The Tubes are much cheaper in the shrader world and the video gives me the incentive to do once the presta tubes get tossed
Here's a hack for next time (if you can't just order them online): Cut one from a motorcycle inner tube, they often have thread going all the way down and a locknut unlike bicycle ones. You can probably get broken ones for free if you ask in a shop.
I only ride mountain bikes so I cannot say how much better a Presta is for road. But I have NEVER understood why any mountain bike would be equipped with a Presta valve. They bend and break and just make no sense. I drilled out my rims for Schrader and never looked back.
A valve cut from a tube has a small base, and does not work well for a tubeless valve. But in theory it could be threaded, getting the correct die will be difficult. Then you must hold the valve while cutting.
@@antiantiantiantiantiantian9766 I already own a full 64th's set of SAE... :-) Use what you have ;-) Can even undersize and then round file it till perfect.
@@g.fortin3228 You might get away with that if you're careful. It has to end up *round* of course, if you're running tubes you'll get away with a slightly misshapen or oversized hole (ooh-er missus) but not so much with tubeless.
FINALLY someone sane! (at least when it comes to valves). Presta has SO MANY cons, and hardly any pros for mtb'ing. (fragile, clogs, core pops out with screw on pumps, needs fiddling to engage when pumping and often leaks some air until top is screwed tight...). In 20 years of cycling i've never seen a drilled rim snap in the valve hole- and we drilled tons of them back in the ghetto tubeless days. VIVA LA REVOLUTION!
THIS is exactly why i prefer schrader valves. With the added benefit of being able to use virtually any kind of air pump in an emergency without needing an adapter to use. Presta belongs more on a road bike than on an mtb.
Let's not forget the lock nut coming loose while trying to connect / disconnect the pump - that's a load of the fun when the slow hiss becomes a deflated balloon.
I'd love to find someone with experience enough to be confident to make the conversion. Been on Schader stems all my life - every bike / every car - very used to the easy of them. Recently bought a new MTB that came w/ Presta valves and the first 2-3 times I tried to adjust the airpressure - tires went completely flat just trying to close the seal on the pump. Got it to close properly but holy crap had to repump the tires from nothing 2 times and a lil extra coz I lose a ton of air when trying to close the damned Presta valve after removing the pump.
Just what I was thinking as I cringed watching him drill that second hole, I've had drills catch and jump forward quicker than you can say BRAND NEW RIM !
There are ALWAYS Burs. I would attempt to clean up those holes with a Deburing tool or a small Rat Tail File. At least that is what I would do because I could see how any very small burs would eventually cut into the rubber of the New Schrader and therefore create an air leak. In any case, I'm glad to see that there is a Presta to Schrader valve conversion because I am planning on going tubeless on my Gravel bike build. It looks like there is an overwhelming consensuss
Agreed! I can recommend you to try the ConvertAir. Just remove the presta core and screw on the body the ConvertAir. Now you keep the body of the presta but you have the tip of schreder
You are good if there are no burrs. I’m never that lucky. I always deburr after drilling just to be safe. I was a machinist for 30 years and I hate burrs.. LOL. Thanks for all your tips guys. Have a fantastic day..!!
Love having schrader valves in my 29+ rims and have the valve caps with the valve core remover tool. So I can whip the valve core out any time and with a simple syringe, top up my sealant.
Estupenda explicación sobre las válvulas, pero no acabo de entender que vamos todos hacia unificar por ejemplo a USB C y, en cambio, volvemos a una válvula del siglo anterior, salvo por peculiaridades de una llanta de carretera donde no hay otra opción. Hablamos de Schrader (1.500 millones de vehículos) 1 mm de diferencia, no es objeto de rotura de llanta, la practicidad universal, no lleva tuerca, aguantan presiones altísimas como en los tractores, tráiler, motos de enduro etc., comprobar la presión es mucho más práctico, se pueden tubelizar, desmontaje del obús súper práctico, inflado menos arriesgado al inflar con mancha en la montaña al no doblar, me cuesta muchísimo entender ir hacia atrás. De todas formas felicitaciones por el video, sigo mucho tus consejos, eres un gran comentador.
Done a few wheels like this over the past 5 years - works great. The fancy lock nuts used in the vid look great. But a nylon washer helps to maintain tension and protects the rim. To make a perfect diy washer, cut a slice from a Schrader valve cap using a mini hacksaw.
@@nirweisser3233 That looks good, but doesn't fully address the issue in this video of presta being easier to damage. Definitely a good solution for some though.
I know almost nothing about fluid dynamics, but I do know that the flow rate in a tube varies with the fourth power of the inner diameter. Meaning, that if the Schrader valve has twice the inner diameter of the Presta valve, it would actually let air through 16 times as quickly, assuming the same pressure at the air compressor (and assuming that your air hose isn't the limiting factor).
You were only right about one thing - "I know almost nothing about fluid dynamics" You are getting confused with aerodynamics and hydrodynamics. Poiseuille's law or equation is a physical law that gives the pressure drop in an incompressible and Newtonian fluid in laminar flow flowing through a long cylindrical pipe of constant cross section. The assumptions of the equation are that the fluid is incompressible and Newtonian; the flow is laminar through a pipe of constant circular cross-section that is substantially longer than its diameter; and there is no acceleration of fluid in the pipe. For this example the actual fluid flow is not laminar but turbulent, leading to larger pressure drops than calculated by the Hagen-Poiseuille equation. To sum up ... Poiseuille's law: A statement in physics: the velocity of the steady flow of a fluid through a narrow tube varies directly as the pressure and the fourth power of the radius of the tube and inversely as the length of the tube and the coefficient of viscosity.
I have a set of old 26” wheels drilled for schrader that I wanted to set up tubeless. I got some tubeless tires and at the time the only tubeless Schrader valves available from distributors or online was a pair of 32mm Stan’s valves from Amazon. They’ve sealed perfectly and they seem to be really sturdy. With the presta valves on my gravel bike I’ve noticed a lot of sealant getting dried up in the valve stem or valve core. The tire either inflates very slowly or the valve core gets stuck open when I remove the air hose. I’ve had to replace the valve cores a couple times in a year and remove the cores and clean out the valves with a spoke probably a dozen times. If more companies start making tubeless Schrader valves I could see it catching on well
i prefer schrader valves on my mtb, because of removable cores and convenience of fast and easy access to pump and compressors. basically easily and conveniently available everywhere, automotive tire shops, gas stations, you name it, they have it.
Just did my 6th conversion today. With my deep hatred for presta valves, the first 4 were honestly presta tubed to schraeder tubed, and way before this video... I just dont like dealing with Presta valves. One of those I re-converted to Schraeder tubless, and the two since then have been tubeless as well. Without a doubt, this is one of my favorite mods. Park Tool, you guys are killin' it. You've helped me out so many times, and kept the wheels rollin' without an extended time-out at the LBS!
Thanks, you are now part of the SCHRAEDER REVOLUTION!!! There are so many wide rims now, this only makes sense. Every time I add air, I think what a great change this was.
I've done this too. Converted to Schrader tubeless valves on Velcocity; 29 Dually's, 26 Cliffhanger's and 700c Dyad's. 26 Rabbit hole's and most recently 27.5 Stan's sentry's. Spacers are a good idea since those problem solvers nuts have to be ordered. I use nylon spacers from the hardware store instead of metal, these can be sanded to fit on the rim surface if need be. Especially on those Dyad's rims.
Lol you guys are awesome ill be suggesting the conversion immediately you can air up at a gas station without a stupid adapter👍 so many pluses being able to seat a large tire easier is my favorite
I did this years ago on an old guy with 26" rims. Didn't know what the skinny presta valve was called then, I was probably 12 years old. Found the proper drill bit and presto a Schrader hole for a tube I had.
I prefer the presta valve with a schrader adapter. Presta valves are easier to pull out of the stem if stuck with sealant. The adapter keeps me from busting the schrader tip when pulling the pump off the tip. Awesome vid!
just busted my presta tip pulling off the pump while adapter was on it! it broke such that the adapter had the presta tip threading locked in it and would spin and spin without being able to remove the adapter. so now I wont be able to remove the tube and fix my next flat without snapping it off completely. what a dumb problem.
You always take a little emery cloth or other appropriate fine sanding material and polish up a drilled aluminum edge and prove it by touch, you don't just say "no burrs." Must have taken a poll and discovered that most of the readers here have never touched a drill, the way you stress out over the hole. That said you should tell newbies to hand work that the most important safety tool is not the ridiculous goggles, it's appropriate rubberized gloves to grip everything securely. AND, use a very sharp (new) drill bit, dull ones are more apt to dance off the surface. They never mention the best reason to swap, you can get air at a gas station without an adapter.
(sharp) Point taken on the burrs. We will be less in a rush in the future to minimize viewing time. Besides the old gas station stop, there is no skinny Presta tip to get bent. And besides that, you can get the coolest valve caps in Schrader.
@@parktool - I know YOU know all about bike work, but they have you doing takes with a cutsie script, you are likely to overlook things. Get the children out of the room so you and your associate can simply work on a bike NATURALLY. Naturally is better, this scripted presentation tends toward bullshit.
Just another example where road racing technology gets adopted inplaces where it is not the best choice. Tyure unreliablity is a big obstacle to wider use of bicycles. Tubeless should be advantageous, but schrader valves would need to be part of the story except for the narrowest or rims. I tried schrader valves on rims factory drilled for schrader, and still had unresolvable issues sealing the base of the valve.
At our shop we don’t drill rims to convert anymore . We discussed this and the conclusion was , it makes us liable if the rim fails . If you want to do it you are on your own .
I'd never perform those types of procedures before because I would probably mess up the valve permanently. Maybe with the right sizing and precision, I could get the fitting done correctly. Thanks for showing tech Tuesday to me.
I did this on some 11-year old 29" 19mm inner width rims with no problems. Got 3 years + on that conversion. It was a lot easier on the 32mm rims, but no issues with the 19's
Nice! Presta valve has it's advantage: 1. the rim has better mechanical resistance 2. it seals better (the diameter of presta is smaller than schrader) Schrader has it's advantages: 1. way more easy to inflate 2. it's easy to add sealant Thank you for creating this video, it will help a lot of home mechanics.
Cheers for the video park tool, I have been looking for a video like this because I have asked for a tubeless kit for Christmas and I can’t wait to get running the new tubeless wheels👍🏻🤟🏻🇬🇧🚵🏻♂️🇵🇪🏴 P.S would I be able to get some park tool tools for cheap because my dad runs a bike shop and is a big park tool fan as am I, so I was just wondering if I could get a wee cheeky discount 👍🏻🤟🏻🇱🇷
I just started using Presta Valves about a week ago and I broke my first and last Presta Valve today trying to pump up my tire. I never had a Schrader Valve do that to me only through long term wear and tear. Thanks for showing how to do this because I'm going back to Schrader Valve.
@@parktool I just converted my 29er over today. I had to order everything I needed, because my local bike shop didn't have what was needed. Did everything that was suggested in the video and everything went as smooth as silk. Thanks again I am completely happy now.
Nice job, nice clip! I liked the self-made „asher“ you added on top of the presta. This holds the presta tight for sure, the little ring seems to flimsy. Just have the same problem here, but have to go with the little ring…
Interesting.....I have allways have had a Schrader valves & never ran Presta valves. I am building a road bicycle. After some research and educational input, maybe l will try running Presta valves in this new bike.
I don't see why you need two size drill holes. The 21/64 on the inner rim seals it off from air leakage (along with tension nut). The 19/64 on the outer rim can only serve to make for tighter fit for rest of fully threaded valve (standard rubber sided valve won't fit so spare tube needs to be fully threaded schrader..harder to find) and that should not be needed if using a tension nut in the first place.
I did a DIY conversion on my dirt jumper, used a schrader valve because that's what inner tube had. The conversion worked just fine even tough I used a regular rim and tire (no tubeless specific parts.) I did use sealant. The nice thing about the schrader is that you can remove to core. Without the core you can pump a lot of air trough the valve to seat the tire on the rim. You can also pour in sealant once the tire is set, this is a lot less messy. And all you need to do is cut a schrader valve from one of your old flat tubes. (Or get one for free from a local shop!)
I just ordered new tubes w/presta valves for my 29" MTB. Wish I had seen this video beforehand. I'm so sick of these frail little presta valves. Wish manufacturers only used them in the cases that they're needed. #prestavalvehater ;)
Hey Calvin! I've been having shifting issues with an older seven-speed Shimano Altus derailleur on an early 90's mountain bike that I've converted for commuting use. I've checked it over a hundred times -- the derailleur hanger is straight, the chain isn't being pulled half-way between gears, and the chain is definitely the right length. It's currently set up as a 3x7, but as far as I can tell, the front derailleur is in alignment, too, and hasn't given me any problems in the past. And it functions flawlessly and quietly on the stand. Problem is, whenever I'm actually out cycling, shifting under load it makes this incredibly odd sound: Ski-bi dibby dib yo da dub dub Yo da dub dub Ski-bi dibby dib yo da dub dub Yo da dub dub Ski-bi dibby dib yo da dub dub Yo da dub dub Ski-bi dibby dib yo da dub dub Yo da dub dub Ba-da-ba-da-ba-be bop bop bodda bope Bop ba bodda bope Be bop ba bodda bope Bop ba bodda Ba-da-ba-da-ba-be bop ba bodda bope Bop ba bodda bope Be bop ba bodda bope Bop ba bodda bope
I wish that I had done this on my fat bike before installing the tires. My Lezyne XL threads on and can unthread the valve core on a priests if your not careful - bad situation out in the cold....
I just use Aluminium valve caps on my prestas. Problem solved with no hassle and loosing guarantee on my wheels. And the valve caps come in a lot of fancy colours 😁
No you are absolutely correct. It's mostly bullshit unless you like little hobby activities. That said they never mention the best reason; you can get air at a gas station without an adapter.
If you fat bike (run really low pressures), pressure gauges don't work below 10 psi on a Presta valve but Schrader is no problem (even with cheap auto gauges). You can buy gauges specific for low pressure Presta but they are pricey and very fragile. Also if you want to lower your pressures out on the trail in the middle of a Canadian winter, you just need a stick whereas with Presta those valves are a pain to open with heavy gloves on and even worse if you don't close them all the way.
Tried to go tubeless on an old 26” rim with tubeless compatible Panaracer tires and Schrader valves. Bead wouldn’t seat at all. Guess I’ll have to pony up on some tubeless ready 26” wheels but they’re pricey.
7.5 and 8.5mm drill bits for those of us in more advanced countries. Also, if your're going to run more than 35-40 p.s.i. (275 KPa) in your tyres you're better off sticking with Presta: tyres stays up longer with a more positive seal in the valve stem.
Thanks! The metric system is quite nice. I will say that higher pressure systems are perfectly fine with Schrader valves. If presta were better for higher pressure rear shocks running in excess of 500 PSI would use presta. Air planes running 300psi and high heat would use them. There are systems that use schrader valves that run pressures as high as 7000 psi.
Can you help?I don't get the why of the conversion, I've had both valves and often times found the Schraeder on the floor with no air, but happened rarely with presta, so I find presta more reliable, and I don't care about being able to inflate at the station as I carry my own inflator, so other that pure convenience for road riding, why make the change?
Good video gents! Tubeless related question: I recently had a long screw going through my panaracer gravel king AND Stan's grail rim leaving few small holes in the rim. Do I need to replace the rim to bring it back to tubeless ready or will the new rim tape suffice? Thanks in advance!
Depends on the size of the holes and the damage sustained. But, Id venture to guess that you will be fine putting new tape down and rocking it. All depends on the condition though.
Do you seat tubeless with the Schrader valve core installed using the standard chuck? Otherwise, with the compressor tools I have available the extra diameter is only useful when using a floor pump.
You can do it either way. If you are having trouble then remove the valve core. With a compressor the Schrader will flow more air. In almost any situation the Schrader will flow more air as the bottle neck is smaller. A pneumatic system can only flow as much as the smallest orifice will allow.
they make adaptors that convert presta to schrader and sometimes they are included in the small parts kits included in many cheap air compressors. so you could use the adaptors to convert for carbon and narrow wheels.
That is true, but the base stem is still weak. The seal is not so great when inflating and seating the bead of a tubeless tire. Most wide or medium rims can be drilled and converted.
I have been running Schrader for years but i have always had to make my own tubless valves out of tubes. dh tubes worked the best with an extra piece of rubber splicing for extra squish at the contact point. Always did it because i didnt want to use a different air chuck on the compressor
Interesting. Watching the video and reading the comments, it seems like shrader tubeless valves stems are relatively newish. However, going back over 30 years ago when I was doing my motorbike apprenticeship, we used them all the time. I'm not talking about the snap in type like they use on cars, I'm talking about a complete metal stem with a flat rubber washer. They were basically used on all the mag wheels. A quick look on ebay shows at least a few of the type i'm talking about, but there is a different style with 2 stepped rubber washers, which isn't what I was talking about, they would require more mods to fit. Just the single flat washer ones work fine. It might be worth going to your local motorbike shop to see if they have any. I can't see why the still wouldn't sell them.
I've been debating on doing this on my rims for a while now, but I have a set of 2013 Mavic Crossmax STs 29ers on my XC bike, and the rim profile is a little odd shaped to be doing this. It's only a 19mm wide rim so not a lot of room to mess with. Absolutely great video!
I've got standard Schrader type rims, Ryde "Zac2000", on my former touring bike converted to a randonneur. 19mm inside, easy to get tyres on/off without levers. Used Mavic reducer inserts to keep presta valves from rattling. Presta tubeless vents fit in nicely. I even beefed the rubber cone up, plus there's enough room to drill out that fraction of a mm for a schrader valve if need be. Hope that helps.
Thank you for the video it was very informative. I would like to know what size bit you used on the single walled rim was it the 21/64 or the or the 19/64? thank you.
When I converted my rims to schrader I used a sheet metal step bit to clean up the burrs and sharp edges. Done by hand, not drilled. I did the conversion in the first place because presta valves feel so fiddley and imprecise to me. The less time I can spend thumb-screwing tiny nuts the better! 😄
I feel presta valves hold higher pressures better than Schraeder. I must be way behind technology. I have never dealt with these type of rim/tire combinations. I have always used tubes. I have some experience with sew ups. Maybe a video on these type of tire/rim combinations.
Michael Harris try pumping up your shrader to same pressure as presta. It holds. When presta first arrived I was told it can handle higher psi but real life has shown me that Schrader can handle it just fine
Presta valves on MTBs has always been ridiculous. Nice to see another option for tubeless!
I have been using a presta to shrader adapter because that how my air pump is and my compressor . I am still running tubes and I have a bunch of shrader tubes and debated drilling out the rim . The Tubes are much cheaper in the shrader world and the video gives me the incentive to do once the presta tubes get tossed
I converted to tubeless.
I had to use presta valve in a Schrader hole without any problem.
Culd not find Schrader tubeles valves annywhere in Norway.
Here's a hack for next time (if you can't just order them online): Cut one from a motorcycle inner tube, they often have thread going all the way down and a locknut unlike bicycle ones. You can probably get broken ones for free if you ask in a shop.
I only ride mountain bikes so I cannot say how much better a Presta is for road. But I have NEVER understood why any mountain bike would be equipped with a Presta valve. They bend and break and just make no sense. I drilled out my rims for Schrader and never looked back.
So what did y’all use to cover the round weight loss cut outs on the MTN bike rim so that the air wouldn’t leak out installing the tubeless liquid?
You mean the spoke nipple holes? Tubeless rim tape ("strapping tape" or "gorilla tape" are great cheap options).
Ill just use one of those presta to schrader adapter
Can you add additional thread to a scrahder cut from a tube?
A valve cut from a tube has a small base, and does not work well for a tubeless valve. But in theory it could be threaded, getting the correct die will be difficult. Then you must hold the valve while cutting.
Metric: use a 8,5 mm drill bit.
Yeah right.
Those „19/64th“ is really a pain in the ears.
Take it easy, take metric!
:)
@@antiantiantiantiantiantian9766 I already own a full 64th's set of SAE... :-) Use what you have ;-) Can even undersize and then round file it till perfect.
@@g.fortin3228 You might get away with that if you're careful. It has to end up *round* of course, if you're running tubes you'll get away with a slightly misshapen or oversized hole (ooh-er missus) but not so much with tubeless.
They drilled both walls with 7,5mm but only the inner one with 8,5mm, right?
FINALLY someone sane! (at least when it comes to valves). Presta has SO MANY cons, and hardly any pros for mtb'ing. (fragile, clogs, core pops out with screw on pumps, needs fiddling to engage when pumping and often leaks some air until top is screwed tight...). In 20 years of cycling i've never seen a drilled rim snap in the valve hole- and we drilled tons of them back in the ghetto tubeless days.
VIVA LA REVOLUTION!
Hell yeah!!! Schrader = mountain biking
Presta = Spandex, uh I mean road biking
@@austinbergen2409 😂😂💯💯💯
THIS is exactly why i prefer schrader valves. With the added benefit of being able to use virtually any kind of air pump in an emergency without needing an adapter to use. Presta belongs more on a road bike than on an mtb.
I can't believe Presta was ever a thing, especially on MTB, so dumb!
Let's not forget the lock nut coming loose while trying to connect / disconnect the pump - that's a load of the fun when the slow hiss becomes a deflated balloon.
I did this conversion 3 years ago & couldn't be more satisfied with the results! Nice video, guys.
I'd love to find someone with experience enough to be confident to make the conversion. Been on Schader stems all my life - every bike / every car - very used to the easy of them. Recently bought a new MTB that came w/ Presta valves and the first 2-3 times I tried to adjust the airpressure - tires went completely flat just trying to close the seal on the pump. Got it to close properly but holy crap had to repump the tires from nothing 2 times and a lil extra coz I lose a ton of air when trying to close the damned Presta valve after removing the pump.
Install a collar (e.g. pvc tube) on the second drill bit to prevent drilling through both walls of the rim.
They make drill stops, they come in sizes to fit the drill. They secure with an Allen screw.
Just what I was thinking as I cringed watching him drill that second hole, I've had drills catch and jump forward quicker than you can say BRAND NEW RIM !
I've done this six times now, never even nicked the 2nd wall. I am old, wear thick glasses, and I am somewhat clumsy. If I can do it, anyone can.
A piece of tape around the bit is also a good visual indicator of when to stop.
There are ALWAYS Burs. I would attempt to clean up those holes with a Deburing tool or a small Rat Tail File. At least that is what I would do because I could see how any very small burs would eventually cut into the rubber of the New Schrader and therefore create an air leak. In any case, I'm glad to see that there is a Presta to Schrader valve conversion because I am planning on going tubeless on my Gravel bike build. It looks like there is an overwhelming consensuss
Good to hear you will consider the conversion.
On the burr, it passed the finger tip test. No blood was drawn and not edge was felt.
Agreed!
I can recommend you to try the ConvertAir.
Just remove the presta core and screw on the body the ConvertAir. Now you keep the body of the presta but you have the tip of schreder
@@parktool that's gotta be the best method when it comes to safety: no blood was drawn and no eye was blinded.
@@parktool Good test - no blood = no cut rubber - I like it !!
You are good if there are no burrs. I’m never that lucky. I always deburr after drilling just to be safe. I was a machinist for 30 years and I hate burrs.. LOL. Thanks for all your tips guys. Have a fantastic day..!!
Much prefer schrader. Stronger, only one cap to remove, and I can use the same inflator as my car
Love having schrader valves in my 29+ rims and have the valve caps with the valve core remover tool. So I can whip the valve core out any time and with a simple syringe, top up my sealant.
It's about freeken time. Presta blows
What's worse than rocks that come out of nowhere, are trees that run into you! =P
Never liked presta......
VIVA LA REVOLUTION !!!
Estupenda explicación sobre las válvulas, pero no acabo de entender que vamos todos hacia unificar por ejemplo a USB C y, en cambio, volvemos a una válvula del siglo anterior, salvo por peculiaridades de una llanta de carretera donde no hay otra opción.
Hablamos de Schrader (1.500 millones de vehículos) 1 mm de diferencia, no es objeto de rotura de llanta, la practicidad universal, no lleva tuerca, aguantan presiones altísimas como en los tractores, tráiler, motos de enduro etc., comprobar la presión es mucho más práctico, se pueden tubelizar, desmontaje del obús súper práctico, inflado menos arriesgado al inflar con mancha en la montaña al no doblar, me cuesta muchísimo entender ir hacia atrás.
De todas formas felicitaciones por el video, sigo mucho tus consejos, eres un gran comentador.
Done a few wheels like this over the past 5 years - works great. The fancy lock nuts used in the vid look great. But a nylon washer helps to maintain tension and protects the rim. To make a perfect diy washer, cut a slice from a Schrader valve cap using a mini hacksaw.
Presta is inconvenient... Not enough to drill my wheels though.
Agreed!
This is why I use ConvertAir
www.ride-air.com
@@nirweisser3233 That looks good, but doesn't fully address the issue in this video of presta being easier to damage. Definitely a good solution for some though.
I know almost nothing about fluid dynamics, but I do know that the flow rate in a tube varies with the fourth power of the inner diameter. Meaning, that if the Schrader valve has twice the inner diameter of the Presta valve, it would actually let air through 16 times as quickly, assuming the same pressure at the air compressor (and assuming that your air hose isn't the limiting factor).
You were only right about one thing - "I know almost nothing about fluid dynamics"
You are getting confused with aerodynamics and hydrodynamics.
Poiseuille's law or equation is a physical law that gives the pressure drop in an incompressible and Newtonian fluid in laminar flow flowing through a long cylindrical pipe of constant cross section.
The assumptions of the equation are that the fluid is incompressible and Newtonian; the flow is laminar through a pipe of constant circular cross-section that is substantially longer than its diameter; and there is no acceleration of fluid in the pipe. For this example the actual fluid flow is not laminar but turbulent, leading to larger pressure drops than calculated by the Hagen-Poiseuille equation.
To sum up ...
Poiseuille's law: A statement in physics: the velocity of the steady flow of a fluid through a narrow tube varies directly as the pressure and the fourth power of the radius of the tube and inversely as the length of the tube and the coefficient of viscosity.
@@Paul-mz6ss so.... What is the difference in pounds of air?
@@daffodil2067 funny flex huh?...Paul never tied his science jargon back to any conclusion regarding inflating tires.
I have a set of old 26” wheels drilled for schrader that I wanted to set up tubeless. I got some tubeless tires and at the time the only tubeless Schrader valves available from distributors or online was a pair of 32mm Stan’s valves from Amazon. They’ve sealed perfectly and they seem to be really sturdy. With the presta valves on my gravel bike I’ve noticed a lot of sealant getting dried up in the valve stem or valve core. The tire either inflates very slowly or the valve core gets stuck open when I remove the air hose. I’ve had to replace the valve cores a couple times in a year and remove the cores and clean out the valves with a spoke probably a dozen times. If more companies start making tubeless Schrader valves I could see it catching on well
i prefer schrader valves on my mtb, because of removable cores and convenience of fast and easy access to pump and compressors. basically easily and conveniently available everywhere, automotive tire shops, gas stations, you name it, they have it.
My Giant has a Presta valve & I HATE it!! Much prefer Schrader valves.
Just did my 6th conversion today. With my deep hatred for presta valves, the first 4 were honestly presta tubed to schraeder tubed, and way before this video... I just dont like dealing with Presta valves. One of those I re-converted to Schraeder tubless, and the two since then have been tubeless as well. Without a doubt, this is one of my favorite mods.
Park Tool, you guys are killin' it. You've helped me out so many times, and kept the wheels rollin' without an extended time-out at the LBS!
Thanks, you are now part of the SCHRAEDER REVOLUTION!!! There are so many wide rims now, this only makes sense. Every time I add air, I think what a great change this was.
I've done this too. Converted to Schrader tubeless valves on Velcocity; 29 Dually's, 26 Cliffhanger's and 700c Dyad's. 26 Rabbit hole's and most recently 27.5 Stan's sentry's. Spacers are a good idea since those problem solvers nuts have to be ordered. I use nylon spacers from the hardware store instead of metal, these can be sanded to fit on the rim surface if need be. Especially on those Dyad's rims.
I have run Shrader all of my 66 years, i now have Presta Tubeless and I hate Presta , I will make the conversation.
I hate presta, so glad there is a Schrader option. Totally willing to drill a little if needed to get rid of the garbage Prestas on my mountain bike.
If the rim is single wall, why not just use a rubber automotive valve? The kind you pull through and it seats and seals the hole itself.
Lol you guys are awesome ill be suggesting the conversion immediately you can air up at a gas station without a stupid adapter👍 so many pluses being able to seat a large tire easier is my favorite
am SO going to so this the next wheel build. i hate presta valves, always have. but am as old as they are....lol
I subscribed to help get you past the dreaded 666k
I did this years ago on an old guy with 26" rims. Didn't know what the skinny presta valve was called then, I was probably 12 years old. Found the proper drill bit and presto a Schrader hole for a tube I had.
I have unscrewed too many presta inner cores by unscrewing pump or the cap.
Same, whenever I see those, I threadlock them always.
@@airwilliam24 Lol, pro hack indeed. Might just aswell use superglue.
I love and I use Schrader and tubes ...... no complaints so far . Aluminum also , no carbon .
I prefer the presta valve with a schrader adapter. Presta valves are easier to pull out of the stem if stuck with sealant. The adapter keeps me from busting the schrader tip when pulling the pump off the tip. Awesome vid!
just busted my presta tip pulling off the pump while adapter was on it! it broke such that the adapter had the presta tip threading locked in it and would spin and spin without being able to remove the adapter. so now I wont be able to remove the tube and fix my next flat without snapping it off completely. what a dumb problem.
You always take a little emery cloth or other appropriate fine sanding material and polish up a drilled aluminum edge and prove it by touch, you don't just say "no burrs." Must have taken a poll and discovered that most of the readers here have never touched a drill, the way you stress out over the hole. That said you should tell newbies to hand work that the most important safety tool is not the ridiculous goggles, it's appropriate rubberized gloves to grip everything securely. AND, use a very sharp (new) drill bit, dull ones are more apt to dance off the surface. They never mention the best reason to swap, you can get air at a gas station without an adapter.
(sharp) Point taken on the burrs. We will be less in a rush in the future to minimize viewing time.
Besides the old gas station stop, there is no skinny Presta tip to get bent.
And besides that, you can get the coolest valve caps in Schrader.
@@parktool - I know YOU know all about bike work, but they have you doing takes with a cutsie script, you are likely to overlook things.
Get the children out of the room so you and your associate can simply work on a bike NATURALLY. Naturally is better, this scripted presentation tends toward bullshit.
@@parktool - Any viewer can use the R/L arrow key to skip forward 5sec a click, and we all know this.
Just another example where road racing technology gets adopted inplaces where it is not the best choice.
Tyure unreliablity is a big obstacle to wider use of bicycles. Tubeless should be advantageous, but schrader valves would need to be part of the story except for the narrowest or rims. I tried schrader valves on rims factory drilled for schrader, and still had unresolvable issues sealing the base of the valve.
How about cleaning up those burrs clearly visible on the first rim to avoid any damage to the rubber on the tubeless valve
At our shop we don’t drill rims to convert anymore . We discussed this and the conclusion was , it makes us liable if the rim fails .
If you want to do it you are on your own .
19/64" ~7.54mm; 21/64" ~8.33mm
Someone should make a schrader valve that tapers down to the size of a persta valve so no modifications will be needed.
21/64th hhshahahahahhahahgahahahgaaa. :)
I'd never perform those types of procedures before because I would probably mess up the valve permanently. Maybe with the right sizing and precision, I could get the fitting done correctly.
Thanks for showing tech Tuesday to me.
This is pretty much standard for me. I haven’t done this on my Xc rims though. I’m not sure I will they seem a bit narrow.
Hi,
I can recommend you on the ConvertAir
I did this on some 11-year old 29" 19mm inner width rims with no problems. Got 3 years + on that conversion. It was a lot easier on the 32mm rims, but no issues with the 19's
Sure. I just paid £600 for a wheels ready to drill them 💪🏻💪🏻💪🏻
ive been wanting to switch my mtb to tubeless. Now that theres a schrader valve for Tubeless. I can! Thanks for posting this video
Nice!
Presta valve has it's advantage:
1. the rim has better mechanical resistance
2. it seals better (the diameter of presta is smaller than schrader)
Schrader has it's advantages:
1. way more easy to inflate
2. it's easy to add sealant
Thank you for creating this video, it will help a lot of home mechanics.
3. It's ubiquitous
So I'm guessing I need a bike before I can change the tyre
Where can I find reliable Schrader valves
Stans no tubes.
LMAO - "experiment" on $200 wheels. That's not a tax bracket I'm in.
$200 wheels are cheap.
Cheers for the video park tool, I have been looking for a video like this because I have asked for a tubeless kit for Christmas and I can’t wait to get running the new tubeless wheels👍🏻🤟🏻🇬🇧🚵🏻♂️🇵🇪🏴 P.S would I be able to get some park tool tools for cheap because my dad runs a bike shop and is a big park tool fan as am I, so I was just wondering if I could get a wee cheeky discount 👍🏻🤟🏻🇱🇷
I just started using Presta Valves about a week ago and I broke my first and last Presta Valve today trying to pump up my tire. I never had a Schrader Valve do that to me only through long term wear and tear. Thanks for showing how to do this because I'm going back to Schrader Valve.
Viva La Schrader Revolution!
@@parktool I just converted my 29er over today. I had to order everything I needed, because my local bike shop didn't have what was needed. Did everything that was suggested in the video and everything went as smooth as silk. Thanks again I am completely happy now.
@@Crested-jh3mb I am doing it. Where did you buy the needed parts?
What did you use for the spacer on the single wall? Is that just a washer with a larger ID than the rubber seal?
Yes, It's needed because the taper of the valves can come through and prevent you from tightening the valve in place.
"Time for a nut!" -Calvin Jones
Nice job, nice clip! I liked the self-made „asher“ you added on top of the presta. This holds the presta tight for sure, the little ring seems to flimsy. Just have the same problem here, but have to go with the little ring…
Interesting.....I have allways have had a Schrader valves & never ran Presta valves. I am building a road bicycle. After some research and educational input, maybe l will try running Presta valves in this new bike.
I don't see why you need two size drill holes. The 21/64 on the inner rim seals it off from air leakage (along with tension nut). The 19/64 on the outer rim can only serve to make for tighter fit for rest of fully threaded valve (standard rubber sided valve won't fit so spare tube needs to be fully threaded schrader..harder to find) and that should not be needed if using a tension nut in the first place.
I did a DIY conversion on my dirt jumper, used a schrader valve because that's what inner tube had. The conversion worked just fine even tough I used a regular rim and tire (no tubeless specific parts.) I did use sealant.
The nice thing about the schrader is that you can remove to core. Without the core you can pump a lot of air trough the valve to seat the tire on the rim. You can also pour in sealant once the tire is set, this is a lot less messy. And all you need to do is cut a schrader valve from one of your old flat tubes. (Or get one for free from a local shop!)
I just ordered new tubes w/presta valves for my 29" MTB. Wish I had seen this video beforehand. I'm so sick of these frail little presta valves. Wish manufacturers only used them in the cases that they're needed. #prestavalvehater ;)
Always liked the more versatile schrader valve hole. Gives you the option of using both schrader valve or presta (with an adapter).
If it's dependable, I like it!
Hey Calvin!
I've been having shifting issues with an older seven-speed Shimano Altus derailleur on an early 90's mountain bike that I've converted for commuting use. I've checked it over a hundred times -- the derailleur hanger is straight, the chain isn't being pulled half-way between gears, and the chain is definitely the right length.
It's currently set up as a 3x7, but as far as I can tell, the front derailleur is in alignment, too, and hasn't given me any problems in the past. And it functions flawlessly and quietly on the stand.
Problem is, whenever I'm actually out cycling, shifting under load it makes this incredibly odd sound:
Ski-bi dibby dib yo da dub dub
Yo da dub dub
Ski-bi dibby dib yo da dub dub
Yo da dub dub
Ski-bi dibby dib yo da dub dub
Yo da dub dub
Ski-bi dibby dib yo da dub dub
Yo da dub dub
Ba-da-ba-da-ba-be bop bop bodda bope
Bop ba bodda bope
Be bop ba bodda bope
Bop ba bodda
Ba-da-ba-da-ba-be bop ba bodda bope
Bop ba bodda bope
Be bop ba bodda bope
Bop ba bodda bope
Use a rat-tail to clean the burs.
I was hoping you would rock test the Schrader valve. :(
Good call. Next time.
I wish that I had done this on my fat bike before installing the tires. My Lezyne XL threads on and can unthread the valve core on a priests if your not careful - bad situation out in the cold....
I just use Aluminium valve caps on my prestas. Problem solved with no hassle and loosing guarantee on my wheels. And the valve caps come in a lot of fancy colours 😁
I don't get schrader valves on my country, is it possible to do it with an old tube?
5:12
*Cries in European*
No burrs my ass.
What is reason to swap? I got my both, presta and schrader and never thinking other is better then other. Is there some reason that I missed?
They said it in the video itself pretty clearly. Bulkier, therefore stronger, and allows air to enter faster (wider diameter valve).
seating tubeless tires, adding tubeless sealant, pesky valve removal on presta/ wear and tear can damage presta way easier. I'm gonna give this a go.
No you are absolutely correct. It's mostly bullshit unless you like little hobby activities. That said they never mention the best reason; you can get air at a gas station without an adapter.
If you fat bike (run really low pressures), pressure gauges don't work below 10 psi on a Presta valve but Schrader is no problem (even with cheap auto gauges). You can buy gauges specific for low pressure Presta but they are pricey and very fragile. Also if you want to lower your pressures out on the trail in the middle of a Canadian winter, you just need a stick whereas with Presta those valves are a pain to open with heavy gloves on and even worse if you don't close them all the way.
Can i drill and convert an alex syncros x 39 presta to shrader valve?
I have alloy cap on my presta and I install short valves and no problem with them
Tried to go tubeless on an old 26” rim with tubeless compatible Panaracer tires and Schrader valves. Bead wouldn’t seat at all. Guess I’ll have to pony up on some tubeless ready 26” wheels but they’re pricey.
go read about ghetto tubeless and see if any tips might help on the old rims.
7.5 and 8.5mm drill bits for those of us in more advanced countries. Also, if your're going to run more than 35-40 p.s.i. (275 KPa) in your tyres you're better off sticking with Presta: tyres stays up longer with a more positive seal in the valve stem.
Thanks! The metric system is quite nice. I will say that higher pressure systems are perfectly fine with Schrader valves. If presta were better for higher pressure rear shocks running in excess of 500 PSI would use presta. Air planes running 300psi and high heat would use them. There are systems that use schrader valves that run pressures as high as 7000 psi.
Can you help?I don't get the why of the conversion, I've had both valves and often times found the Schraeder on the floor with no air, but happened rarely with presta, so I find presta more reliable, and I don't care about being able to inflate at the station as I carry my own inflator, so other that pure convenience for road riding, why make the change?
Durability/reliability, convenience, easier setup.
Good video gents! Tubeless related question: I recently had a long screw going through my panaracer gravel king AND Stan's grail rim leaving few small holes in the rim. Do I need to replace the rim to bring it back to tubeless ready or will the new rim tape suffice? Thanks in advance!
Depends on the size of the holes and the damage sustained. But, Id venture to guess that you will be fine putting new tape down and rocking it. All depends on the condition though.
Do you seat tubeless with the Schrader valve core installed using the standard chuck? Otherwise, with the compressor tools I have available the extra diameter is only useful when using a floor pump.
You can do it either way. If you are having trouble then remove the valve core. With a compressor the Schrader will flow more air. In almost any situation the Schrader will flow more air as the bottle neck is smaller. A pneumatic system can only flow as much as the smallest orifice will allow.
my dad is going to love this, get his bike going with schraders.
they make adaptors that convert presta to schrader and sometimes they are included in the small parts kits included in many cheap air compressors.
so you could use the adaptors to convert for carbon and narrow wheels.
That is true, but the base stem is still weak. The seal is not so great when inflating and seating the bead of a tubeless tire. Most wide or medium rims can be drilled and converted.
I have been running Schrader for years but i have always had to make my own tubless valves out of tubes. dh tubes worked the best with an extra piece of rubber splicing for extra squish at the contact point. Always did it because i didnt want to use a different air chuck on the compressor
Interesting. Watching the video and reading the comments, it seems like shrader tubeless valves stems are relatively newish.
However, going back over 30 years ago when I was doing my motorbike apprenticeship, we used them all the time. I'm not talking about the snap in type like they use on cars, I'm talking about a complete metal stem with a flat rubber washer. They were basically used on all the mag wheels. A quick look on ebay shows at least a few of the type i'm talking about, but there is a different style with 2 stepped rubber washers, which isn't what I was talking about, they would require more mods to fit. Just the single flat washer ones work fine.
It might be worth going to your local motorbike shop to see if they have any. I can't see why the still wouldn't sell them.
I've been debating on doing this on my rims for a while now, but I have a set of 2013 Mavic Crossmax STs 29ers on my XC bike, and the rim profile is a little odd shaped to be doing this. It's only a 19mm wide rim so not a lot of room to mess with.
Absolutely great video!
I've got standard Schrader type rims, Ryde "Zac2000", on my former touring bike converted to a randonneur. 19mm inside, easy to get tyres on/off without levers. Used Mavic reducer inserts to keep presta valves from rattling. Presta tubeless vents fit in nicely. I even beefed the rubber cone up, plus there's enough room to drill out that fraction of a mm for a schrader valve if need be. Hope that helps.
is the guy big or the road wheel tiny??
Schrader anytime, but it costs too much.
Damn! General Ross needs to juice up
How do you get these things off? Is the rim ruined if you want to go back to tubes?
You can simply remove the valve and install a tube.
Thank you for the video it was very informative. I would like to know what size bit you used on the single walled rim was it the 21/64 or the or the 19/64? thank you.
19/64 that a single wall rim.
@@parktool thank you for your reply will note that on my Trike maintenace work sheet.
When I converted my rims to schrader I used a sheet metal step bit to clean up the burrs and sharp edges. Done by hand, not drilled.
I did the conversion in the first place because presta valves feel so fiddley and imprecise to me. The less time I can spend thumb-screwing tiny nuts the better! 😄
I feel presta valves hold higher pressures better than Schraeder. I must be way behind technology. I have never dealt with these type of rim/tire combinations. I have always used tubes. I have some experience with sew ups. Maybe a video on these type of tire/rim combinations.
What valves and pressures do commercial airplanes run?
Michael Harris try pumping up your shrader to same pressure as presta. It holds. When presta first arrived I was told it can handle higher psi but real life has shown me that Schrader can handle it just fine
oof cant tell if i hate or love the cheesiness
I’ve mentioned the ‘cheesiness’ numerous times. I wish they would stop it and explain their theory as if the audience are adults.
Its brilliant, relax and the ennoy cheesy humour
You love it.
Does Park Tool make a nice tubeless valve?
We do not. We make tools and not components. Stans or B&W make them at this time.
Nice video.
I have done this many times .
Good job
Use a rubber grommet instead of a metal washer
Brilliant!😄
What is the narrowest rim one can drill for a good schreader valve fit?
Excellent question. We do not have an official answer at this time. Id say no narrower than 20mm.
THANK YOU! and you are talking top inside edge to top inside edge correct? NOT the "valley" edges width, right?
Nice
Hello Bonjour ! Thank you !!!
JRA!