Making a switch here to 35mm tires, up from the previous 32's.

700x 28/32 presta tubes are as close as your nearest Wal-Mart and are on the shelf in most every LBS.

700x 35/43's not so much.

So, if I run 28/32mm tubes in 35mm Schwalbes should I expect any problems?

Thanks,
Mike

Will not be a problem at all. I ran 700x18-25 tubes in 700x28s and 700x32s for thousands of miles. If anything, it just makes the tires easier to mount, because the uninflated tubes are smaller in diameter.

No problem at all

Itll work.

With that said, there is a limit. A 23mm tube in a 40mm tire is dumb and not safe as the tube isnt made to expand that much.

Have you tried pumping up a 23mm tube outside a tyre?

I can guarantee the diameter it gets to is more than 40mm, and it's nowhere near bursting. Think balloon. It might be slightly less durable, but still usable.

I've used 23mm tubes in 32mm tyres before now. No problems.

Yup, ive pumped a 23mm tube outside a tire.
Yup, it get massive. Fat bike tire sized.
Nope, it shouldn't be something you use just to save a few bucks. If its all you have when you get a flat riding, sure. But there is no reason to seek out 23s for 40s (or bigger).
I used 40mm tires as an example, but bump it out to 2" 29er tires if you want. The point remains that there is a limit within reason.
There is no reason to overinflate a small tube just to make it large enough to fill the tire cavity when a properly sized tube is available.

My car can rev to 8000rpm and can go 130. That doesnt mean it was made to run for extended time at those limits. Hope you get the analogy.

Some even select a tube one size smaller than a given tire size on purpose, they claim it gives them a more supple ride and of course if you're a gram counter, it saves rotational weight.

Or the Inverse.. put thorn resistant tubes in . they're thicker , & more-so on the road side than the rim side.

9 month tour of SW Ireland to NE Scotland (including lots of time just hanging out with the Locals)

Had no punctures.

Done this by mistake before. Never knew it until I changed the tire a year later!

The analogy is ridiculous and irrelevant.

Wow you seem testy.
There is a limit to using a small tube in a large tire. Do you agree or disagree?


If you agree, then you have been responding in an argumentstive manner for no reason as you may not like the specific size i mention, but thats the hardly as important as the main point which is that there is a limit to the difference between tube size and tire size. Just name the limit you think is acceptable and be done.


If you disagre and your position is that a 23 tube can go in any sized tire, then state that directly and be done.

As for the car analogy...a 23mm tube can work in my 40mm tires but it isnt ideal or meant to be used in that manner for an extended period of time. Same with the engine. It can do high speed, but not for extended time.



If a 23mm tube were meant to be used in that manner, then there wouldnt be larger tubes made. This isnt a marketing ploy since a 23mm and a 43mm tube cost the same.

Your analogy of revving a car engine is irrelevant to this discussion. And now you are demanding I agree or disagree with a changed argument. You can read what I have stated and take it or leave it.

Yeah, I use light tubes sized a little small. When carrying spare tubes you save the weight on the two in the tires and a the ones in the seat wedge. Also they pack a lot smaller.

As was mentioned they are a bit easier to install and way less likely to get pinched during installation.

There is a slightly livelier ride feel. It is like having a bit more supple sidewall. It is subtle enough that you probably won't notice unless comparing this approach to full sized thorn proof tubes..

One down side I have found is that lighter and/or under-size tubes do lose air more quickly, so you need to top them up more often. I figure the advantages make it worth the more frequent topping up.

makes it easier to put on the tire if it's a tight rim/tire combo.

slightly increases rolling resistance, small enough you'll never notice but it's there.

Yes, there is a limit to how much the rubber will stretch but going from a 23mm tire to a 32mm tire isn't even coming close to the limits. People seem to get hung up on just how big an millimeter is...possibly be cause it's a whole number instead of a fraction. The difference is 9mm. To put it into something concrete, that's the thickness of 4 nickels and 1 dime. Or it's a bit less than 3/8". Not much at all.

A 32mm tube in a 35 mm tire isn't even enough to worry about.

That's a poor analogy. Stretching a tube over the nominal size is more like stretching a piece of elastic too far. It will stretch but eventually the elastic may not spring back. But it takes a very long time.

Yup, id use a 23 in a 32 if necessary. I didnt say that such a size difference is coming to the tube's limits.
Yup, i agree a 32 in a 35 isnt anything to worry about which is why i posted that itll work.


I said a 23 in a 40 is dumb because there is no need for it. Want a smaller tube in a 40?...use a 32. Tubes come in multiple sizes for a reason and a small difference like 32 in a 35 which is the OPs question is nothing to think twice about. But there is a reason why tubes come in different sizes.
I use 35-43s for my 40mm tires so clearly there is a safe and acceptable variance in tire size for tubes.

Perhaps 23 in a 40 isnt a large enough difference, but i would think it is and wouldnt use a 23 unless i didnt have a choice. So say 23 in a 2" 29er. Or 23 in an even wider tire. The point was that small differences are ok but there is a limit. Thats all.

I agree with the others it'll work fine.

Downside: Loses air more quickly and somewhat more prone to puncture.

If I had a bike shop inventory in my garage I'd probably always use the nominally 'proper' sized tube. But since my most-used bike has 23mm wide, 622mm diameter tires it's more convenient to sometimes just use that size tube even in my touring bike that currently has 38mm wide tires since the narrow tubes do work as well (albeit needing slightly more frequent filling). For that matter, I sometimes just carry a 622mm diameter tube for use on my folding bike with 451mm diameter tires since again they work fine and I don't always have the smaller tubes in my personal inventory. Using what you have available at the time doesn't make it 'dumb' if a trip to the store at that time would be inconvenient and what you do have available actually works just about as well.

There are a number of high quality tubes that will cover your needs. Two I've used extensively are the Schwalbe SV18 (28-44 x 700 at only 105 gm) only found them online in the US and they are expensive, but they are all I tour with these days. Another tube carried by lots of LBS is the Continental Tour (32-47 x 700 at 150 gm), resonably priced. The Tour is seamless making it really easy to patch.

All but the very cheapest tubes rated for 32 can make it to 35. I've never bought a Walmart tube so I'll withhold comment.

Thanks for that. Experience always trumps theory. Always.

The original question related to very small differences between tube specs and tyre specs. It wasn't an issue, and still isn't, to use the smaller tube.

Going back about a decade, there was a competition held somewhere (probably the UK) to nominate the number of pumps it would take to burst a bicycle tube. Really, for this discussion, the size was irrelevant. There were the usual 100 or maybe 200, but in the end it took over 800, IIRC, to do it.

To the OP, yes, that tube will work just fine for you.
Do tubes have working limitations? Of course they do.
Will members here argue about anything? You can count on it!

And you are the one who brought up using a 23mm tube in a 40mm tire. I don't see anyone saying that a 23mm tube should be used in a 40mm tire.

That said, you are still hanging up on millimeters. The difference between a 40mm tire and a 23 tire is only 17mm which is less than 3/4" difference. To put it another way, that's only 6 more millimeters. That's not a lot. And it's not outside the ability of a tube to stretch nor would it cause any damage to the tube.

From personal experience, I use 23mm tubes regularly in Vitoria tires that are marketed as 35mm tires but are marked "622-37". They are wider than most 35mm tires I've seen. I even use the Quality Bicycle Products Q-tubes Superlights which have a thinner wall than the regular tubes. If I thought I need an extra (and trivial) 3mm of width, I wouldn't have a problem using the same tubes.

Again, a 32 in a 35 is nothing to care about ir think twice about.

With that said yet again, i do think there is a limit at which using smaller diameter tubes no longer makes sense.
I have used smaller diameter tubes in large tires and i think they arent as durable or long lasting. Total guess, but i think its because the tube is stretched thinner than it was intended.

A 40mm tire has about 215% more volume than a 23mm tire. 100% more is twice as much volume, and this is 215% more. Yes, we can talk how few millimeters difference the tires are. Volume difference though?...what a tube is made to do (fill space), is significantly different.


I am shocked (but i guess not really) that this has continued so long.
Its really surprising to see anyone argue my original point of- the op's situation will work, however there are limits.

Yes, there is a large increase in the volume but that's not the important measurement. How much the tube stretches is important and that is related to the surface area of the tube which only increases by 82% when a 23mm tube is used in a 40mm tire. Rubber can stretch from 500% to 700% so it's no where near the limits.

I've never had much success with thorn resistant tubes, and conceptually to me at least they make little sense. I figure once a sharp object penetrates the tire body sooner or later you're gonna go flat, slime tubes being a possible exception.

Of course, actual experience with these things may differ.

Mike