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

 

[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

 

[Andy]

Thanks Tony. Much appreciated.

"Tony W" <[email protected]> wrote in message news:2l4hmfF8g1f9U1@uni-
berlin.de...
>
> "Andy" <Please reply to the group> wrote in message ne-
> ws:[email protected]
> d.com...
> > 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

 

[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 <okhvr1-
[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 ;-)