Which Tube size for 700 x 28 tyres?

[Borderbiker]

Just bought some winter tyres for bike. They are 700 x 28.

I have loads of 700 x 23 tubes so wonder if i can risk them , if not what best size tube.

Thanks

[Vantage]

Personally, I'd have no worries using them.
A lot of riders deliberately use undersized tubes because they pack smaller and weigh less (must save that 100th of a gram).
Most tubes (all?) will cover a range of sizes due to their elasticity and that will vary even more when you consider that stated tyre sizes can vary from manufacturer to manufacturer, so your 28mm tyres may only measure 25 or 26mm.
Welcome to the forum btw

[Erudin]

I use Continental Race 28's labeled 700 x 18-25c with 28mm Gatorskins. I used to use Continental Tour 28 Slim Tube for tyre size 28-37 but the Race 28's are cheaper off Ebay and work as well.

[RickH]

The only real disadvantage with slightly narrow tubes is that patching punctures may be harder to do reliaby due to the stretching of the tube in use.

Rick

[AM7]

I've been using Specialized 700x20/28c inner tubes in 700x35 tyres for the last couple of years with no problems

[Slowroad]

Bought an inner tube for my 700 x 28 tyres from Wheels In Motion in Chard while on tour, and the chatty and helpful owner told me that this size tyre is in between sizes and you can get narrow tubes and wider ones. (I'd noticed over the years - 25 of them - with this bike that I've been sold a range of sizes!) He recommends narrow ones as there is less chance of getting a snakebite puncture where a bit of inner tube is pinched between rim and tyre.
Information like this, subjective though it is, is far more useful than the usual: "Here you are, £6 please"!

[sreten]

Hi,

If you have loads of 23mm tubes then its a nobrainer, use them.
They will go down a little faster, and might not repair as well.

rgds, sreten.

[GrumpyGit]

With my engineering background I'd always go for components that have a bit of slack in the specification, so in this case I'd be looking at tubes with at least 32 as the upper limit so that they aren't overstretched at working pressure.

[sreten]

Hi,

Well most road tubes are 23mm to 28mm by default, what more can I say ?

rgds, sreten.

[niggle]

With my engineering background I'd always go for components that have a bit of slack in the specification, so in this case I'd be looking at tubes with at least 32 as the upper limit so that they aren't overstretched at working pressure.

Over size tubes can be difficult to fit in the tyre without creases, which can cause punctures over time, or pinching the tube under the tyre bead, which will cause a rather quicker puncture or even blow out; whereas slightly under size tubes are very easy to fit and avoid these issues. Anyway it would be more weight for no gain and added expense for the OP who has a supply of 23mm tubes.

I use Michelin Ultra Light 18-23m tubes in 28mm tyres with no problems. They do go down a bit quicker than some, but that is probaly partly due to being ultralight, standard thickness 23mm tubes will be just fine. I also use 28-32mm Michelin standard weight tubes in 35mm tyres, again with no problems and these hold pressue well.

I suggest the OP goes ahead using the 23mm tubes then reports back if there is a problem, and I predict that we will never hear from him about it again

[goatwarden]

With my engineering background I'd always go for components that have a bit of slack in the specification, so in this case I'd be looking at tubes with at least 32 as the upper limit so that they aren't overstretched at working pressure.

In the case of metal objects this approach would normally make sense. However if you inflate any tube outside the tyre, so it can expand freely, it will comfortably go to several times the constrained diameter and not explode when touched harshly (like a baloon might). So, the difference in wall thickness of a nominal 23mm tube when pressurised within a 23 or a 32mm carcass is minimal; i.e. there is a massive safety allowance built into any tube already.

Some manufacturers market "lightweight" tubes. I somehow doubt these are manufactured from magically strong and thin rubber, but just a thinner version of the rubber used in standard tubes. Thus a lightweight tube in a size matched carcass is unlikely to be any different in terms of safety, puncture resistance or air-tightness than a standard tube in a carcass a few mm bigger than the nominal size of the tube.

[Borderbiker]

Wow,
Thank you for all your replies.

It would make sense to use my 700 x 23 tubes as a start and see how it goes.
The tyres are Giant P-R3's which are a bit puncture resistant so might get away with a bit of over inflation.

But your info is always handy to have and appreciate help.

Hope i can help others someday