Introduction: Making Your Own Self-sealing Presta Valve Bicycle Tube

Picture of Making Your Own Self-sealing Presta Valve Bicycle Tube

Out here, in the desert town of Kalgoorlie, Western Australia, my bicycles and I have one mortal enemy. It is Zygophyllaceae, Caltrop Family - known as puncture vine, goats heads, double gees and sometimes bindi-bindi. There's a photo of these horrible plants here. They are a noxious weed out here, and this year we had more rain than usual so there are lots of them around.

I have two bikes - one is a mountain bike running Sun Rhynolite rims, with presta valves (26" wheels), the other is a flat bar roadie running 28mm 700c tyres. I have had 10 punctures across both the bikes in the 3 months I have been living in town, despite running 'Mr Tuffy's' tyre liners and heavy duty tubes.

I am told that there are only two effective ways to save my sanity by reducing the number of punctures I get - one involves spending $120 on a set of tyres, the other is putting slime in the tubes. Problem with slime is that you can't push it in through a presta valve and tubes with presta valves with removable cores are rare in 28mm or 26" x 2.125 versions.

So I decided to go old school. In this instructable I will show you how to make your current presta valve tubes into self sealing slime tubes with a little bit of surgery.

PS - slime in your tyres will add a noticable amount to the rolling weight of your bike, so it takes some getting used to, but it's worth it in order to prevent those annoying punctures.

Step 1: Find Something to 'push' the Slime Through

Picture of Find Something to 'push' the Slime Through

As we can't push the slime through the valve of a Presta tube, we need to make a hole in the tube in order to inject the slime. Obviously we want to make this puncture hole as small as possible so that it is easy to patch later.

I used the tip of this pen in order to push slime through the small hole we are about to make in the tube.... you can use anything though, just remember that the slime clots if the hole is too small (it guarantees to self-seal any hole 3mm or smaller in the tube), making it impossible to push any more through, so you need a balance between the ease of patching the hole and having it big enough to actually get the slime in there.

Step 2: Put Your 'funnel' on to the End of the Provided Slime Tube

Picture of Put Your 'funnel' on to the End of the Provided Slime Tube

My pen tip was slightly too wide for the provided slime tube, so I cut the tube a little, and then forced it in.

I used standard sticky tape (cellotape) which was lying around the house to provide a better seal.

Step 3: Puncture the Tube!

Picture of Puncture the Tube!

This is hard to bring yourself to do, but get a sharp knife and use it to make a hole in the tube just big enough to slip your slime injector nozzle in to.

Step 4: Squirt in the Slime

Picture of Squirt in the Slime

Carefully insert your slime-nozzle through the hole. Squeeze the bottle gently, and go slowly. Wriggle the nozzle around to ensure that some air gets back into the bottle, allowing you to squeeze in more slime. The slime manufacturers recommend 1/4 of this bottle per tyre (8 oz) but I put a little less in and it's still effective.

Step 5: Clean and Dry the Tube

Picture of Clean and Dry the Tube

Wipe the tube with a bit of toilet paper to get rid of any excess or overflowing slime. This is very important because the vulcanising glue does not work so well when there's still slime on the surface.

Step 6: Prepare for Patching

Picture of Prepare for Patching

Rough up the surface of the tube with one of those metal things that look like cheese graters - you should be able to find one in any bicycle patch kit.

Then apply the vulcanising glue over an area which is approximately the same size & shape as the patch you are going to use.

Let the glue dry (i.e doesn't feel 'tacky' to the touch)

Step 7: Apply the Patch

Picture of Apply the Patch

Peel the patch from it's foil backing, place it on the patch of glue, and then using a mug or tin or rolling pin, roll back and forth over it very vigourously until the plastic on the surface of the patch gets wrinkly and splits.

Peel off the plastic, and there you have a patched self healing tyre. Make sure that when you are peeling the plastic off the patch that you peel it from the middle of the patch to the edge of the patch - otherwise the edges could stretch up off the tube and affect the quality of the seal.

Now put the tube back in the tyre, the tyre back on the wheel, and make sure that you rotate the wheel straight after inflating it to distribute the slime evenly - it will also seal any small holes that may have triggered this slime-ing tyre surgery in the first place ;)


FuR1 (author)2014-09-13

You fool! If you grab the flat side of the cap threads on a presta valve, the whole valve unscrews from the stem. Wrap some tape on it > Fill it> Screw valve back in.

Why on earth would you cut a perfectly good tube???

asadabdul (author)FuR12015-08-17

What happens to the "be nice" comment policy? Surely you are aware that not all presta valves have removeable cores, don't you? By the eighth pic it seems that the tube used in this 'ible has a no removeable one.

Solidwrks (author)2012-02-09

I need to make a small inner tube for a project. I cannot get a custom one made at a smaller size. The length of the tubing should be just 110 mm. i have to use a valve that is made of rubber, plastic or stainless steel ( last option) . The tube goes into a magnet, so i have to be careful that the valve i use must not be iron or any attracting materials. Is there a possibility to make it at home.

knx bandit (author)2011-10-16

some presta valve tubes come with removable valve core, "continental" brand tubes are one but there are others. Then use a 50ml syringe from your local hospital or pharmacy to squirt in some slime in. It's that easy. I like in Kununurra WA and too have loads of prickles. Try tyres like "continental protection series MTB 26" or continental gator hard shell road tyres, or any tyre that offers an extra layer of kevlar or tough materal in the manufacture. Good luck

getack (author)2010-05-25

 Well, the newest in thing is to go TUBELESS...
Apparently the probability of a puncture is next to nil.
Very expensive ($100) conversion, but I think it's worth it. 

You can always just buy a tube with slime in it already. I have a slime tube in my saddle bag by default. In South Africa's bike shops we usually have a whole shelf dedicated to anti-puncture products.

Regarding increased rolling-inertia: If you are on a road bike in a race speeding at 50-60 km/h rooting for a record, THEN only will rolling inertia make a difference. And in that case you will have no punctures to worry about. Slower XC's or MTB's will be unnafected. If you are still worried about it, use slime and tyre-liners, with tyres that has less knobblies. Increased rolling inertia with decreased rolling resitance will cancel eachother out.

creative zen (author)2008-04-12

do you have to fill the whole tire with slime? If so, wouldnt that make the tires heavy and make riding your bike a chore? If you dont fill the whole tire up wouldnt the slime settle at the bottom of the tire and make it harder to peddle or something?

jet_ski (author)creative zen2008-04-12

Nah, just maybe 100ml - it does add to the rolling weight of the bike but it only took me a couple of days of riding to adjust - the rims are heavy anyway as this is bike is built for dirtjumping so it's not that much extra

creative zen (author)jet_ski2008-04-13

how much does the slime cost

jet_ski (author)creative zen2008-04-13

I got it from a bike shop for $30, that bottle does 4 to 5 bottles

sharlston (author)jet_ski2009-09-18

seroiusly i used it in my 20 inch bmx tires and it only lasted me 2 syres

jet_ski (author)jet_ski2008-04-13

4 to 5 tyres I mean!~

lasersage (author)2008-04-11

don't know about your particular wheels, but i find standard 26" rims often come with the presta valve size, but i just drill it out to fit a schrader.

jet_ski (author)lasersage2008-04-12

You can run higher pressure with presta valves, I like having the option therefore I am loathe to drill out my Sun Rhynolites.

Prometheus (author)jet_ski2008-04-30

The valve suyppied with an innertube means nothing to how much pressure the tire can take. Schrader valves can take over 3000PSI, but are more common. Presta valves are a failing attempt to change a stubborn american standard to accept a metric standard with the rest of the world. There are adapters available to adapt the primitive Schrader air chucks for use with a Presta valve, just ask your local bike shop. These allow you to use 19th century technology to inflate your Presta valves until the USA catches up to the rest of the world (don't hold your breath).

just because Shrader valves have been around a while doesn't mean they aren't any good! Yes presta might be a slightly more advanced valve that does not use springs but nothing beats the simplicity of just pushing the shrader air chuck up to the valve to fill it with air. With a presta you have to unscrew it, fill it, and then re screw it. Also on a presta valve the parts are exposed but on the shrader vales everything is inside the valve tube. another thing is I can completely replace the shrader valve if needed; can you do that with presta valves? what happens if you take a well placed hit to the presta valve that bends the screw such that you can no longer fill it with air? so its not a matter of metric vs. standard. I am all for the metric system but shrader all the way!!

The advantage to Presta valves is that there is no fear of a leaky core, allowing a guaranteed seal. Compatibility, I agree with, but taking a hit on a Presta valve is immeasurably improbable. Bends on the core spindle are always the result of improper handling. Also, it is uncommon for even a bent core not to seal unless it breaks off. Presta has the advantage of a greater flow rate through the valve, and not relying on spring-pressure to retain a seal. The greater flow rate makes hand-pumping faster and less physical work. While it appears exposed, openings are far too small to allow the ingress of water, which is a vehicle for dirt. A Presta valve's main advantage is fitting into ultra-narrow rims on road bikes, since a Schrader valve's required dimension would dangerously weaken the rim beyond an acceptable standard, such as with rims 10mm wide on 700C wheels. You simply can't use a Schrader valve on that rim, and no Tour De France rider will ever take wider rims just to fit a Schrader valve. IMHO, no mountain-bike should be equipped Presta, as using 10mm wide rims on such is simply unreasonable, despite alleged performance. Too narrow, and the tire/tube combo could simply roll of the rim when cornering. Also why I will never use a tubular tire...I can never feel safe relying on glue to keep the tire on (I don't think weight-savings is worth the risk, but I used to have diesel-powered legs that bent many frames and broke many chains, so weight is less important to me (I broke chains by pin/plate separation on links not related to the link I mounted it on by sheer power alone...I know because I always marked links that were mounted or dismounted, and never was a pin driven to or from any link more than once. I promise not from poor chain mounting). Presta has it's superiorities, but I agree that despite that, Schrader valves should be the standard due to a replaceable core and it's current prevalence. While it has it's troubles with sealing perfectly, and dirt ingress, it's probably an acceptable standard. Always keep them capped firmly to protect from water, dirt, and dust. Don't bother cleaning cores, just replace them, even if you have to go to a junkyard and nab one off a tire, or by getting them from old innertubes. If you do clean them, use only rubbing alcohol. Screw in finger-tight only.

i think i have a presta valve stem that has gone bad; are they replaceable like schrader stems or are you stuck buying a new tube? thanks very much.

You are stuck buying a new tube, Presta valves are not in any way serviceable. If your rim is greater than 18mm wide, you could consider drilling it out for Schrader valves... Save the innertube itself though, they are remarkably-versatile, and is the best patch material you can use, far better than the patches included. All you really need is the vulcanizing glue...They have many other uses as well...

fuzvulf (author)jet_ski2009-03-06

30 years ago I had some lace-ons with tubes that had Schraeder valves which took 200 psi, how much pressure do you want? Not meaning to sound rude but I don't think the pressure holding capability is a matter of the design but of where you get them. Prestas are smaller thereby the rim is not weakened as much, there is not as much air resistance, the weight of the valve itself is less providing greater balance to the wheel, also due to the nut on many designs*(which Schraeder used occasionally have but due to market pressure they became harder and harder to find.) it is more durable for riding in areas where rocks or other foreign objects might damage a Schaeder. This same feature also allows one to run at lower pressures when rock climbing on bike without the tube sliding within the tire and rim.

lasersage (author)jet_ski2008-04-14

fair enough, I know a lot of cross country riders who swear by presta, quicker to inflate/deflate from what i hear as well. I'll stick with my schraders for simplicity. Don't be to precious about you rhynolites though, i drilled my sun big fat mammoth (i didn't care how expensiver rim it was, it needed to do a job :)

are presta valve stems unscrewable and replaceable like schrader stems? any one know? thanks.

HappyToBeAlive (author)2008-10-24

lasersagesays: don't know about your particular wheels, but i find standard 26" rims often come with the presta valve size, but i just drill it out to fit a schrader. ROFLMAO. I thought I was the only one who did that?

7O7 (author)2008-09-23

This almost seems like its a bit too late but you don't have to cut the tube at all. Okay you have to follow me on this one and I will instruct you through a better way to do it. You know the little knurled nut that threads up and down to allow you to put air in/out. Well pinch the tube with your fingers right by the valve to prevent the valve from falling inside the tube after you take that knurled nut all the way off. Yea that's right just unscrew it all the way off (use some small pliers if you need to). BUT be careful to catch the valve core by feeling through the tube (it's like holding the valve core with a rubber glove on so don't let it get away). Once you are holding the valve core, put the sealant tube and bottle FIRMLY over the valve and add 1/2" bottle. Of course hold the valve up to allow room for the sealant to flow. Now since you are still holding the valve core through the rubber and hopefully with the tip of it pretty close to the hole, feed it back into the valve and wiggle or tap it until it falls back through. once you see the threads you're home free. Now just pinch the tube with you fingers again to keep it from sneaking back inside, then thread the little nut back on. Thread the nut down and pinch the tip of the threads with the pliers to mess up the threads just a little and there you have it sealant in the tube with out cutting it. I hope I didn't make it sound too complicated, I can do this in about 5 minutes and have done hundreds of prestas this way.

runner1212 (author)2008-07-05

I would just like to know whether or not anyone has done this and can attest that doing this DOES in fact prevent puncturing?

night (author)2008-05-15

hey, any problems letting air out of the tyres, i have heard stories of the slime coming out too and ruining the valve,

PyromaniacDaniel (author)night2008-05-24

you can avoid this if you orient the valve so that it is just below the horizontal axis of the wheel such that it slants back towards the wheel to let the slime run out of it and back into the wheel but sits high enough on the wheel that it is above the pool in the bottom of the tube. sorry its an easy concept just hard to describe.

The picture should say enough here, and good advice to all.

jet_ski (author)night2008-05-16

this can happen, but it hasn't happened to me yet... I've heard similar stories though...

lynzay_ (author)2008-05-02

INSIDER SECRET. for anyone wanting to make an instructable on puncture proof tyres, here it is. line the inside of your bike tyre with an old car seatbelt, seatbelts are made with such a strong heavy weave you wont be getting punctures anytime soon , and for safety, use the thicker inner tubes. INDESTRUCTABLE.

jongscx (author)lynzay_2008-05-02

Seatbelts are WOVEN NYLON. They are good at resisting lateral stresses (like when they hold a person back) but a thorn will go right between the weaves... You can sew through a seatbelt with a needle by hand, it's not that hard. This is also the same way that a person can stab through a kevlar vest with a really sharp spike. If you've done it, I'm betting it's the added thickness that is keeping your tube safe, not necessarily that the belt is is . Thicker Inner-tubes do work. But they're not puncture-proof, just puncture-resistant...

jet_ski (author)jongscx2008-05-16

the seatbelt is a good way of adding thickness without adding as much weight as the same amount of rubber - but yeah it would stab through the weave easily enough.

autolycos (author)2008-04-11

You can take insert slime into a presta valved tube provided you use some dexterity and pliers. Use the pliers to take the nut off, just keep screwing it past the mashed threads, it'll come off--but when it does, prepare to capture the inner part as it falls into the tube. Then, just add your slime. Screw the nut back on, and using the pliers, crush the top one or two turns of the threads so that the nut can't be removed by fingers.

trailgrind (author)autolycos2008-05-15

I have used a different method so as not to damage any of the threads. You take a metal file and just file a little off from the screw and then you can unscrew the nut with ease. After filling the tube with slime, you just twist the nut back on and just tap the end with a ballpeen hammer a few times (not too hard or you will bend the screw) it works great and my slime tubes last me a really long time, plus it is cheaper than buying tubes that already have the slime in them.

skeptikool (author)2008-05-15

The fix seems incredibly easy. I would remove the tube to inject the latex, or pre-prepare a spare. It would be easier to clean and roughen where you were going to puncture the tube, before doing so. For this, I favor something like a medium sized knitting needle . With care one need not end up with two holes - though this would not be serious. If one were putting the latex into a tube punctured in use, even a hole that had been made by a thumb tack may be stretched to accept the nozzle of the latex bottle. A properly patched tube is in no way inferior to one that has received no puncture at all.

toilofday (author)2008-04-13

You shouldn't use a knife. Slime isn't recommended for the type of puncture a blade inflicts. You should use a nail then stretch the rubber over your funnel. It may be more difficult, but there is less risk of ruining the tube.

jet_ski (author)toilofday2008-04-13

that's why it's patched with vulcanising glue - the slime doesn't heal the slash hole, the patch does!

toilofday (author)jet_ski2008-04-14

True, but not everybody may be as careful when removing the excess slime residue when patching the tire. If you are going to puncture the tire, you might as well make it so there are 2 forces actively sealing the hole, rather than 1 which can fail if not done just right. Maybe I'm just a fan of overkill. Either way 2 is better than 1 Nice Instructable.

jongscx (author)toilofday2008-05-02

But that's not really his problem. The instructables clearly state to clean it well, any failure caused by the user's lack of diligence should not be pushed onto the author.

jet_ski (author)toilofday2008-04-15

I still think that even if you make a round, nail shaped hole it would be too big for the slime to seal well....and if it's too small it is hard to push the slime through. Thanks for your input though!

Prometheus (author)jet_ski2008-04-30

If Slime® won't seal it, the tube is bey9ond a patch anyway.

Lucky (author)2008-04-18

This is nice, but at this point I'd have to wonder if a more direct approach would be better. What I mean to say is that it seems a lot of work to avoid a problem that shouldn't exist in the first place. Maybe inner-tubes could be replaced by multiple layers of shock/bump absorbing soft rubber and foam. Maybe then the tires would never "go flat". I've seen R.C. cars with a rudimentary form of this. I forsee a layer of foam nearest the tire for small rocks and such, which precedes gradually more dense materials until the rim itself be reached. I would only suppose that overal performance loss would occur, even with proper application. However the detriments of the environments traveled through where such a system would be implemented would surely provide adequate hinderance to ensure said system's usefullness.

Prometheus (author)Lucky2008-04-26

There are solid-core tires that have been available for years, but the trouble is that once the tire wears out, they are extraordinarily hard to remove, sometimes resulting in the destruction of the tire and inner liner itself as well. They come available as an add-on for "industrial bikes", but in limited sizes. They are a real BEAR to mount, work great for the tire's lifetime, and even harder to remove to replace the tire casing, especially if you want to preserve the liner itself. You have a visionary stance on this method, but "flat-proof" inserts are expensive and incredibly hard to mount and dismount. In most cases, it's worth the effort, but they are also heavy. I was a "diesel" (brute power cyclist exceeding 0.5HP, 7/8th HP on sprint...I was a "dirty", meaning I rode a MTB) cyclist myself, so maybe little difference to me, but for many, it makes a big difference in performance, especially for "roadies". Flat-proof inserts are only for the highest-torque "roadies", due to rotational mass. I could break a chain on an MTB with road gearing by sheer power alone, but I was an exception. most will have trouble getting a solid-core tire up to speed as fast (although a great training tool).....but most will iike to see their power net results in speed and acceleration, so solid-inserts are out for them. I know with how hard I was on my tires, solid inserts would have been a real pain, and would fail to feel "solid" enough compared to my 80PSI 26X2.25 tires @ 70MPH (a not uncommon speed for me on mine when I could ride). IN any case, I'd recommend Slime, or at the least carry a patch-kit and pump as well. Also, have a dollar bill on you to help patch sidewall tears temporarily.

Prometheus (author)2008-04-26

I might also add that simply drilling out the hole for a Schrader valve is just as easy on the same rim, and can save cost, but there is limitations. You can also get Presta-to-Schrader inflation adapters (so you can use a Schrader pump on Presta valves) to achieve the same. See your local bike shop and ask about them. DO NOT EVER drill a Presta-valved "clincher" (beaded tire with separate innertube, like the lower-end standard) rim narrower than 14mm total width, especially 700C wheel rims. Drilling out a narrow rim can compromise rim strength too much to be safe, and cause a buckle-point if hit the right way. NEVER EVER drill a tubular-tire rim (aka "glue-on"/"stitcher"/"modular"/"beadless") under any circumstances. NEVER modify a tubular rim as they are less structurally-sound, and frankly obsolete from the start in my cyclist experience. Tubular tires are just more risk than I'll take with cornering on any bike as a (now forcibly-retired) cyclist of over 20 years. I've never trusted a tire held on with glue more than a tire held on by itself, and I never will.

silliou (author)2008-04-22

Why not just use puncture proof liners for your tyres? goes between the tyre and the tube. I think Slime make some, they about about 30 bucks for a pair, stops 3 corner jacks, cowtrop, even small nails etc......

Prometheus (author)silliou2008-04-26

I agree, their have been kevlar tire liners for years now in all sizes from 0.9mm 700C to 26"x2.8". They are thorn-proof and only add a few dozen grams to rotating mass depending on the size of the tire. Get them by treadwall width, instead of tire size for best protection. Set them so that the overlap offsets the valve stem.

ashwinhyde (author)2008-04-13

This Instructable is pretty good but isn't the cartridge of a pen flimsy? I think you should probably use a needle to push the slime through.

jet_ski (author)ashwinhyde2008-04-13

Nope, not flimsy at all, its a good solid pen. And you can wash it off and put it back on the pen if you like.

ashwinhyde (author)2008-04-13

nice Instructable

Bubbler (author)2008-04-11

Cat Heads, Three Cornered Jacks, they are nasty. A good tip for all bike riders is to make a semi circle of fine wire, and hang it across the top strung between the forks or off of the mudguard. The tyre picks up the thorn, but it usually doesn't get hammered into the tube until it reaches the bottom of the rotation next time. Before it does, the wire will have ripped it out of the tyre surface. A bit of fiddling and you will get it just right and most prickles will be wiped off.

Tyre = tire Tire equals sleep.

When Slime is added, I think you need to run the wheel for a good while to smear the inner surface well.

jet_ski (author)Bubbler2008-04-12

that's an interesting one... I reckon I might have a play with that method and see how it works :)

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