Newbie question about tubes and tyres

[Andy]

Hi,

Please excuse the probable dumb question coming up ...

My tyres are 700*35c. Do I need to look for a tube that is 700*35c? Also,
I see many other tubes quoted as 26*1.5 (for example). Is this Imperial and
can I convert to metric and use on my bike?

Many thanks for any advice,
Andy.

 

[Tony W]

"Andy" <Please reply to the group> wrote in message
news:[email protected]...
> Hi,
>
> Please excuse the probable dumb question coming up ...
>
> My tyres are 700*35c. Do I need to look for a tube that is 700*35c?
Also,
> I see many other tubes quoted as 26*1.5 (for example). Is this Imperial
and
> can I convert to metric and use on my bike?

Yes.

Tubes are sized. Typically a tube will cover several widths of tyre and
will be marked with something like 700*25-35 -- i.e. it will stretch to
cover 25, 28, 32 and 35 mm wide 700 mm wheel tyres. Different manufacturers
have subtly different ranges.

700 mm is the standard metric road bike wheel size -- broadly replacing the
old imperial 27" wheel.

26" wheels are (mostly) the standard mountain bike wheel size (bloody
'mericans can't understand proper measures) -- so a 26*1.5 would fit a 1.5
inch wide tyre on a 26" wheel.

There are still older 26" standard wheels -- for old sit up and beg, 3 speed
roadsters. These are a different 26" -- if could be arsed to look it up I
could give you the mm sizes of them and the modern MTB wheels.

The job of an inner tube is to stretch inside the space made by the tyre &
rim and to keep the air in. Naturally there is a range over which they can
stretch (think of how you can blow identical balloons up to different
sizes). However, in this case the tube holds the air in while the tyre/rim
sets the size limits (like blowing a balloon up in a small box).

The other thing to look for is what type of valve you want.

T

 

[Andy]

Thanks Tony. Much appreciated.


"Tony W" <[email protected]> wrote in message
news:[email protected]...
>
> "Andy" <Please reply to the group> wrote in message
> news:[email protected]...
> > Hi,
> >
> > Please excuse the probable dumb question coming up ...
> >
> > My tyres are 700*35c. Do I need to look for a tube that is 700*35c?
> Also,
> > I see many other tubes quoted as 26*1.5 (for example). Is this Imperial
> and
> > can I convert to metric and use on my bike?
>
> Yes.
>
> Tubes are sized. Typically a tube will cover several widths of tyre and
> will be marked with something like 700*25-35 -- i.e. it will stretch to
> cover 25, 28, 32 and 35 mm wide 700 mm wheel tyres. Different
manufacturers
> have subtly different ranges.
>
> 700 mm is the standard metric road bike wheel size -- broadly replacing
the
> old imperial 27" wheel.
>
> 26" wheels are (mostly) the standard mountain bike wheel size (bloody
> 'mericans can't understand proper measures) -- so a 26*1.5 would fit a 1.5
> inch wide tyre on a 26" wheel.
>
> There are still older 26" standard wheels -- for old sit up and beg, 3
speed
> roadsters. These are a different 26" -- if could be arsed to look it up
I
> could give you the mm sizes of them and the modern MTB wheels.
>
> The job of an inner tube is to stretch inside the space made by the tyre &
> rim and to keep the air in. Naturally there is a range over which they
can
> stretch (think of how you can blow identical balloons up to different
> sizes). However, in this case the tube holds the air in while the
tyre/rim
> sets the size limits (like blowing a balloon up in a small box).
>
> The other thing to look for is what type of valve you want.
>
> T
>
>

 

[Simon Brooke]

in message <[email protected]>,
"Andy" <Please reply to the group> ('') wrote:

> Hi,
>
> Please excuse the probable dumb question coming up ...
>
> My tyres are 700*35c. Do I need to look for a tube that is 700*35c?

No, but you do need tubes which are 700 and will fit 35. Tubes are
moderately stretchy and one tube will usually be marked to fit several
different widths of tyre (not an indefinite range). Tubes won't
generally fit different wheel diameters.

> Also,
> I see many other tubes quoted as 26*1.5 (for example). Is this
> Imperial and can I convert to metric and use on my bike?

Ish. 700c is very nearly (but not quite) the same as the old 27 inch
standard. It's not the same as 26 inch. Virtually all road bikes have
changed over to the metric standard, virtually no mountain bikes have.
No, I don't know why.

--
[email protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

;; If you're doing this for fun, do what seems fun. If you're
;; doing it for money, stop now.
;; Rainer Deyke

 

[Pete Biggs]

Andy wrote:

> My tyres are 700*35c. Do I need to look for a tube that is 700*35c?

Tubes are usually marked with a width range, eg. 32-38. Any that
encompass 35mm will do, and in fact slightly outside that range will work
as well. Bear in mind that, all else being equal, narrower tubes are
easier to fit and weigh less, but will require inflating more often and
may not be so durable -- that's because the narrower tube has to stretch
more so becomes thinner, making it more porous and delicate. Thickness
varies from one make/model to another.

~PB

 

[Roger Hughes]

In article <[email protected]>,
[email protected] says...
>
> Ish. 700c is very nearly (but not quite) the same as the old 27 inch
> standard. It's not the same as 26 inch. Virtually all road bikes have
> changed over to the metric standard, virtually no mountain bikes have.
> No, I don't know why.
>
>
The real dimensions are all metric, though, defined in millimetres; it's
only the nomenclature and nominal dimensions that mix and match units.

Roger

 

[MartinM]

Simon Brooke <[email protected]> wrote in message news:<okhvr1-

> Ish. 700c is very nearly (but not quite) the same as the old 27 inch
> standard. It's not the same as 26 inch. Virtually all road bikes have
> changed over to the metric standard, virtually no mountain bikes have.
> No, I don't know why.

The *new* 26 is not the same as the old; the rim diameter is much less
to account for the deeper tyres. You can still get old fashioned 26x 1
3/8
tyres but they will not fit an MTB rim; nor will a 27 x 1 1/4 fit a
700c.
The continentals will of course tell you they are not 26 inch but
(cannot be arsed to go out to the garage) mm ;-)