Many wheel and tyre companies are pushing tubeless tyres and wheels at the moment. For those who don’t know, tubeless tyres are similar to a clincher, but form an air-tight seal against the rim and contain sealant, instead of an inner tube.

We previously did an experiment to see if a tubeless road tyre could survive a nail being hammered into the carcass. The result was that it can seal and is very impressive. Further to that we’ve tubeless tyres through the winter on the road and remain very impressed.

This got us thinking. What would happen if you put tubeless sealant inside a standard inner tube and then put it in a normal clincher tyre set up on your existing wheels? Would it work and would it still seal punctures?

We used Stan's No Tubes Sealant

We used Stan’s No Tubes Sealant

>>> American Classic Road Tubeless Wheel review

We have decided to do an experiment to find out. To put the sealant inside the inner tubes we removed the valve cores – you can do this with a special key, or gently with some pliers. If you use the latter, be careful not to strip the thread.

This will only work if your tubes have removable valve cores.

This will only work if your tubes have removable valve cores.

Next we injected sealant into the inner tubes, while deflated inside the tyre. This is a little messy and you may need to spin the wheel a couple of times to get the sealant moving around the tube. We used about 25-30 mL per tube.

>>> Click here for our buyer’s guide to road bike wheels

a valve key. pliers can also be used

a valve key. pliers can also be used

Next we replaced the valve core and pumped up the tyre as normal to around 90-100 psi. For reference we used Continental Grand Sport Tyres, Continental Butyl inner tubes and Stan’s No Tubes Sealant.

The Test

Sticking multiple drawing pins into the tyre and tube was attempted. In all cases the punctures were sealed in a matter of seconds, with minimum air loss. It is necessary to spin the wheel to replicate the centrifugal force of riding and push the sealant to the outside of the wheel.

the system easily seals multiple drawing pins

the system easily seals multiple drawing pins

Next we tried the nail. We were surprised to see that this also works. Although it does take slightly longer to seal. So there you have it… It works!

even a nail can seal!

Even a nail hole can seal!

Verdict

Although it will dramatically reduce your puncture risk, it is not quite as a effective as sealing punctures as a dedicated tubeless set up. That said, even a dedicated tubeless set up won’t completely stop punctures and fitting standard clincher tyres is much easier than tubeless ones.

>>> Buyer’s guide to road bike tyres

A bit of air and sealant escaping from the nail hole

A bit of air and sealant escaping from the nail hole

Tubeless tyres can be very difficult to fit, especially with cold hands. This set up is also significantly cheaper. It means you only need to buy some sealant, which is relatively inexpensive. Investing in a full tubeless set up involves wheels, tyres and special pump to blow the tyre onto the rim (much more costly).

Inserting sealant can be a little messy, but is easier than fitting most tubeless tyres

Inserting sealant can be a little messy, but is easier than fitting most tubeless tyres

The only real downside to this is that it adds roughly 25 grams of rotating weight to your tyre. Nutty weight weenies might be put off by this, but if it means you don’t have to get covered in crap, shivering while trying to change a puncture in the freezing rain of a winters ride then it is surely a no brainer.

To quote Neil Buchanan from Art Attack, “try it yourself.”

  • RonDassel

    I did some experimenting with this earlier this year. I do not encounter too many thorns or thumb tacks as were demonstrated in the video. but with sealant in my tubes I ran onto some cracked up asphalt after a down hill run and got a snake bite flat. I was riding on a 700 X 26 tire which was flat within 100 yards. I tried to inflate the tire with co2 but was happy I had not forgotten to pack an extra tube. not sure this is a great idea, due to the added weight of the sealant and the tube I felt the ride to be a bit slower in acceleration and climbing. I may do some more experimenting in the future, but for now I will just carry and extra tube and a patch kit….

  • Jordan

    You are right, not very lucky. I had several nail punctures and a lot of tire thread getting in my wheel. I also banked over 9,000 miles last year, so, I had plenty of opportunity.

  • getoverit

    How did you get so many flats in the first place? I wouldn’t call you Mr. or Ms. lucky.

  • getoverit

    Hi Gus-it’s nice when someone with experience actually comments rather than the vast number of people who are just guessing-lol. Makes sense like you say that you have found it dries out and that it would make changing a tube with a big cut quite a mess. Thanks for the info.

  • getoverit

    You kind of wonder when people don’t know the limited number of cycling terms that are out there and you kind of wonder why some people claim to get so many flats (might want to learn how to replace a tube properly and or learn to go around glass a bit more often).

  • Shaun Roberts

    One question: the info on this stuff says it’ll stay liquid for “2-7 months”. So at best this procedure will last a summer. Surely then you’d have to throw away the two tubes in use (per bike), as it’d make no sense to add in more – it’d get heavier with each addition, and is presumably then solid. Not saying this is a big problem … just clarifying how to use this approach, if I go for it. Like the idea of having big-time puncture protection, especially for something like a week-long trip.

  • Graham Dunn

    Makes sense Jordan. Thanks. I”ll post as soon as I try it.

  • briantrousers

    Cycling Weekly = “a legitimate source”. That is so awesome.

  • Jordan

    I’m saying I have been doing this for the past year and have yet to have an issue with leaking. Give it a shot. Manufactures say not to fill the tube because they can sell more tubes. If you get a set of Q-Tubes with removable cores in the valve stem, no issue at all. The key feature in the purchase of any tube I have ever bought since starting this, was removable cores in the tubes. Of course, I have 10 extra tubes now because I buy by the dozen and haven’t had to touch the other ones yet.

  • Aidan mongan

    I’m saying that if you get a standard presta tube and take the core out to fill it with sealant it will leak afterwords. Your tubless setup works with presta because you don’t have to take the valve apart to fill it

  • Jordan

    If the valve will leak, then how do you explain that tubeless set ups use presta valves? I have never had an issue with mine over the past year. Slime tubes are pretty much rubbish from my experience. They end up being way heavier than this set up as well.

  • Gus Lock

    You can also use the emergency sealant that comes in car toolkits that don’t have a spare wheel. Suppliers can’t sell the replacement bottles (500ml) if there’s under a year left on the use-by date, so shop around for some freebie stock 😉

  • Aidan mongan

    Our shop sells slime tubes and presta tubes are not supposed to be filled with slime. The valve will leak. Slime sell prefilled presta tubes. Schrader tubes can be converted to slime tubes with no problems

  • Jordan

    Nope. Buy 2 tubes and a bottle of sealant save $3 us. Also, slime tubes have some major issues with leaky valves which then get filled with the slime. I have tried them and they lasted about a month.

  • Jordan

    I’ve never run into a top up air issue in the morning with this set up. It seals better than tubeless on big holes thanks to having an extra layer of pressure for the Stan’s to bond.

  • Jordan

    I’ve tried the slime tubes, they aren’t wonderful. Also, they cost more than this potentially can depending on how/where you buy your Stan’s and tubes.

  • Jordan

    I have been using this method on my fatbike tires and still have the same pressure. Not sure if it will save from a pinch flat or snake bike, but hasn’t been an issue yet. I refill my Stan’s once a year and that is all I need. Where in tubeless you run the issue of it forming a bond in the seal, the tube provides an extra layer of pressure and helps fill the hole faster. I swear by this set up.

  • Jordan

    (1) If you seal the tube, patch kits are obsolete and new tubes don’t matter. A 4oz bottle will cost about $5 and seal 2 tubes which cost about $3. Savings of $1 there. you also do not need to refill the tube but once a season where in riding 2 years ago, I went through 7 tubes…. Lot’s of overall savings

    (2) I have ridden my bike on the same tubes (had to replace tires) for the past year and have not had a deflate issue in the cold. I have pulled out truck tire thread, nails, screws, etc. no issues. I just did a ride yesterday (36 degree Fahrenheit) and check pressure before and after (I was curious about this as well), and had no change. Fill your tubes and enjoy the ride.

  • Jordan

    I’ve been doing this for the past year, first on my fat bike and then next on my Roadie when I was running into puncture issues along Route 66/I-40 in the US where there is massive amounts of debris in the road. My tires are still sealed wonderfully and have actually never had a deflate issue like standard tubeless. I have been preaching this for a while and I guess some people will take is seriously now that there is a legitimate source saying it.

  • Mateusz Sobanski

    Slime inner tubes don’t have removable valves. Their valves are leaky (at least in all the tubes I’ve used) and the sealant clogs it. After some time it’s impossible to pump up the tyre. To change the inner tube I had to cut the valve because I couldn’t deflate it.
    I suppose with removable valve you can regularly clean it

  • Aidan mongan

    Slime tubes cost the same as two standard tubes but they work very well. Probably cheaper than this method too

  • Graham Dunn

    What if you already have some sealant like I do? I’ll give it a go. Getting a road bike and want to go puncture proof on a budget. BTW I’ve never had to stop once with my Hutchinson Toros tubeless set up on my MTB running 30-35 psi! A few top ups of air is all I’ve needed.

  • John McNab

    Thanks Glenn. I hadn’t head that term used in that context before. I’m afraid to say I interpreted it literally at first. Ooops!

  • briantrousers

    Why don’t you just use Slime inner tubes, which are pre loaded with sealant, than all this faffing? You’ve bodged an invention that already exists.

    Try using Google next time and save yourselves the bother.

    Twonks.

  • Patrick94GSR .

    2:32 yeah he definitely watches Casey Neistat vlogs.

  • Graham Shortt

    Bike shop.

  • Glenn Y

    When the inner tube is pinched between the rim and whatever you strike (curb, pothole, etc.) it usually only occurs when tire pressures are lower like on Touring and commuter bikes.

  • Marc Tufano

    So where do you buy it from?

  • John McNab

    Snake bites??

  • Gus Lock

    I use sealant in my MTB tyres without tubes. It works fine for smaller punctures (thorns, pins) and it looks like it’ll do the same for road tyres. Bigger splits and tears (flints, glass, snake bites) may not seal and could make a real mess of the frame if you don’t clean the sealant off.
    Note that the sealant dries out after time and requires topping up. Warm weather and leaks from punctures will accelerate this. Not sure if the same goes for sealant contained in a tube. Looks worth a try.

  • Jmac

    (1) It’s not meant to be cost effective – it’s meant to be convenient, in that it saves you having to change a tyre at the side of the road, in driving rain, on a cold winter’s night.

    (2) Rider sitting on the bike won’t make much difference – the pressure in the tyre is not materially greater when you are sitting on the bike. Cold weather might make some difference, but it would probably still seal quickly enough to leave enough pressure to get you home safely. It’s obviously not a perfect solution – I’d still be carrying a spare inner tube and tools, but that doesn’t mean it’s not worth trying.

  • dourscot

    Two obvious issues:

    1. Isn’t a replacement inner a lot cheaper than sealant and therefore more cost-effective?
    2. Would the sealant continue to work as well with a rider sitting on the bike or in cold weather conditions?

  • ReturnOfTheWazz

    Cool shades, bro.