Before i drill a second valve hole , has anyone used 2 tubes in the rear tyre/tire? im thinking 2 light weight tubes which will be lighter than a heavy duty tube filled with sealant , i am a cheap arse so it will be a cheap thing to do . Not really sure about the pressures eg 2x10psi=20psi or 2x20psi=20psi????
Using two tubes .
- Thread starter ari
- Start date
Ark
Active member
I'd just skip breakfast if you want to save a few grams
Don't do two tubes. At speed, it will create harmonic vibration that causes the derailleur to jump around. What you need is an odd number of tubes. That's why one tube is so popular. If you're going to do anything, put in THREE tubes. Aside from the vibration damping, three is 50% better than two.
fasterjason
Member
You can have two identical half-sized tubes inside the same tire, but they must spin in opposite directions so that they do not violate the Pauli exclusion principle. Otherwise (at the macroscopic scale) your wheel becomes unstable and undergoes drastic volume reduction, i.e. a flat tire.Don't do two tubes. At speed, it will create harmonic vibration that causes the derailleur to jump around. What you need is an odd number of tubes. That's why one tube is so popular. If you're going to do anything, put in THREE tubes. Aside from the vibration damping, three is 50% better than two.
Jokes aside, I want some of what OP is smoking.
Dude! You had me laughing out loud here. Wife and dogs think I've gone nuts.
Ark
Active member
Do you think they rub together when riding and sound like a wet fart
I think you're just massively increasing the risk of some form of internal pinch flat and considerably more friction wear between the two tubes as they interact - they'll have to intertwine at some point to both share valve outlets on the rim.
Seems like you're trying to re-invent the wheel so to speak. ..
Seems like you're trying to re-invent the wheel so to speak. ..
Surely properly tubeless would be the solution?
steve_sordy
Wedding Crasher
Go for proper tubeless. No need to buy another tyre, just go tubeless. All you have to do is to buy a tubeless valve and some sealant. You will save weight and almost 100% stop flats (you won't stop getting punctures, but almost zero flats).
PS: If, despite all advice to the contrary, you insist on proceeding with two inner tubes, then I would inflate each one in stages. The objective is to get each tube similarly inflated. If you fill one up to 20psi and then inflate the other you will discover that very few strokes of the pump will give you 20psi. That is because the first tube is pressing on the second tube. If you keep inflating the second tube, the pressure will rise quickly. Whatever pressure you stop at, the first tube will be the same because the second tube is pressing upon it.
PPS: If you want to stick with tubes and want to save weight, then go for extra strong latex tubes by Tubolito. Even big ones (27.5 x 2.8) only weigh about 30g. I only carry them in case of an emergency when they tyre is too badly damged for the sealant to seal it and a tyre plug doesn't work. I carry two because I have differebt wheel sizes.
Ark
Active member
the tubes will rub together created friction that creates heat and eventually one of them will probably fail surely from a hole won in them
I’m not anti-tube anymore but I don’t use them, or carry a spare. I’m thankful that the rider who found me half laying in a creek had one. (27.5” btw).
After he found my iPhone, and called for help, he placed my arm in a sling with the tube. The doctors at the ER were impressed.
I still have that tube…but it’s a 27.5”
After he found my iPhone, and called for help, he placed my arm in a sling with the tube. The doctors at the ER were impressed.
I still have that tube…but it’s a 27.5”
steve_sordy
Wedding Crasher
It doesn’t matter. Some of us are just adding to the many options and uses of rubber tire tubes.
Hey! They could eventually become a fashion accessory.
…or a backup bike helmet?
- Thread starter
- #15
It was a proper question , but all i got was rude smart arse comments , which i reported , it seems the moderator is pretty slack with his code of conduct rules and taking the piss also . Why would any manufacturer have anything to do with this bullying clown show.
.
steve_sordy
Wedding Crasher
Of the 13 posts in between your first and second posts, there were six that were not trying to be funny. That is not a bad response for such a potentially humorous question. That does not qualify for "but all I got were rude smart arse comments" is a factual yes or no type of statement. It is clearly in error. "Smart arse" I would concede, because that is what passes for humour on many websites these days. "Rude" I would dispute, I have been on the receiving end of "rude" comments on websites and these don't come even near to qualifying. I accept that they may be unwelcome when asking what you thought was a reasonable question, but hey, every day is a learning day. If you ignore the "smart arse" comment, you will have definitely learned something about tyres, tubes, tubeless and sealant.
"Bullying clown show" I would 100% dispute. This is a very good natured and extremely helpful website. Occasionally it is laugh out loud funny, frequently when someone invites the humour, but sometimes they inadvertently make us all laugh (as in your case). But sometimes a post just cannot bring the right sense of humour to the site. The wrong sense of humour tends to get an intervention by the Sheriff, but both sides have to have a sense of humour or this website would be dull, dull, dull.
You only have to look at the " Ep8 turning backwards help please" thread to see that. @ari Don't abandon the site, take a deep breath and carry on. Return with a different username if you prefer, but don't cut off your nose to spite your face, this site has value.
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I mostly feel bad for the moderators. They are probably confused, perplexed and slightly lesser educated after reading this post/thread . I don’t envy their position. 
I bet they are relieved that this is a virtual care home and not a real oneI mostly feel bad for the moderators. They are probably confused, perplexed and slightly lesser educated after reading this post/thread . I don’t envy their position.
I completely agreeI bet they are relieved that this is a virtual care home and not a real one
. The only diaper they have to change is their own. Our time will come though.
steve_sordy
Wedding Crasher
When that time comes, I can recommend "Bepanthen".I completely agree
Our time will come though.
If it works for babies and protects against shit and piss, which is why it works for my modest needs.
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NOBODY has spoken up who has actual knowledge of putting two tubes in one tire. All the responses have been hypothetical conjecture. They're all jealous that they didn't come up with this brilliant idea first. So, Ari, go ahead and drill a hole in your rim and install another tube. Go ride it. And let us know how awesome it is. Thank you.
Surely the question should be ... if two tubes is lighter and better than one, then where do you stop ??
Lets start with 12 - it's easy to work out the holes, keep your wheels balanced and on average you'll drill out 5kg's of wheel if you also switch to Schrader at the same time.
There's then the question of what knitting pattern to use optimally when combining your tubes for optimum support as they fail and to avoid friction failure. Two tubes is going to create lots of sub optimal 90 degree tube contact points, more tubes lessens that issue.
Do you chalk or lube the tubes ??? @steve_sordy you probably have the most experience here from parallel life experiences.
I don't know about anyone else, but I'm really not looking forward to putting a tyre over this beast ?
Personally, I think the whole thing has a lot of merit, but only if you fill one tube with beer or wine and have on tap drinks available from your bike under pressure for easy access for yourself and friends - or new friends when they see what you have.
Thank goodness someone here is sensible, and has practical advice for the OP.
I was thinking maybe a 29er tyre fitted over a 27.5 might give extra protection.
- Thread starter
- #27
Ok then , but it wasn't too much to ask the moderators to ban 6 people , to make the forum more pleasant , I can pretty much guarantee every time you ban the few fools,stirrers, smart arses , you get many more posters/participants[even the ones who have left], the mods did not even delete my thread , which shows they are no better than the clowns.Of the 13 posts in between your first and second posts, there were six that were not trying to be funny. That is not a bad response for such a potentially humorous question. That does not qualify for "but all I got were rude smart arse comments" is a factual yes or no type of statement. It is clearly in error. "Smart arse" I would concede, because that is what passes for humour on many websites these days. "Rude" I would dispute, I have been on the receiving end of "rude" comments on websites and these don't come even near to qualifying. I accept that they may be unwelcome when asking what you thought was a reasonable question, but hey, every day is a learning day. If you ignore the "smart arse" comment, you will have definitely learned something about tyres, tubes, tubeless and sealant.
"Bullying clown show" I would 100% dispute. This is a very good natured and extremely helpful website. Occasionally it is laugh out loud funny, frequently when someone invites the humour, but sometimes they inadvertently make us all laugh (as in your case). But sometimes a post just cannot bring the right sense of humour to the site. The wrong sense of humour tends to get an intervention by the Sheriff, but both sides have to have a sense of humour or this website would be dull, dull, dull.
@ari Don't abandon the site, take a deep breath and carry on. Return with a different username if you prefer, but don't cut off your nose to spite your face, this site has value.
Yup, but you like fat bikes and are obsessed with bigger is better .. any normal person would suggest stuffing a 26 inside the 27.5 then you have a spare
This is on the watch list so rather than continuing to waste the moderators time with this thread I'll respond publicly.
You post a thread which sound like an April fools joke - even if you're serious.
You think we should ban 6 people who have a good sense of humour - for being humorous and you think that's a reasonable course of action ??
Why would we delete your thread ? You haven't asked us ? If we did, you'd complain that we were being unfair.
When you initially REPEATEDLY (we're not deaf or blind even if some are old and incontinent) reported your own thread, we suggested you explained further purporting the advantages and disadvantages of your proposal - you didn't.
You then continued to report people responding to the thread and STILL didn't engage in any form of discussion.
When people did respond with more serious proposals - you STILL didn't respond.
What is it exactly that you want ? You haven't actually discussed your proposal further in the thread.
To make things clear, if you use the report function again without it being reasonable you will be banned from the forum as people have better things to do with their lives than dealing with your time timewasting.
Likewise, if you think this is a discussion - it isn't ! Keep the thread on track if you wish - that's your call - any response will be taken as a request for your account removal.
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