rim width revisted... (20"/406 wheels)



C

C.J.Patten

Guest
Howdy folks.

Thinking of putting narrow tires on my 20" rims (406's - folding bike).
They came with 1.95 knobby tires, I'm down to 1.50 slicks.

I measured the rim width and it's 1 inch. I'd like to put Schwalbe Marathon
slicks on which are 20x1.35's.

Can I get away with this without worrying about them popping off? (or just
popping)

Thanks.
Chris
 

daveornee

New Member
Sep 18, 2003
2,763
0
0
C.J.Patten said:
Howdy folks.

Thinking of putting narrow tires on my 20" rims (406's - folding bike).
They came with 1.95 knobby tires, I'm down to 1.50 slicks.

I measured the rim width and it's 1 inch. I'd like to put Schwalbe Marathon
slicks on which are 20x1.35's.

Can I get away with this without worrying about them popping off? (or just
popping)

Thanks.
Chris
What model rim?
What is their inside width?
What condition is the rim in?
What pressure will you inflate the tire to?
 
C

C.J.Patten

Guest
"daveornee" <[email protected]> wrote in
message news:[email protected]

> What model rim?


I don't have a model number but it's an aluminum rim, 32-spoke, conventional
brake, clincher and, as mentioned, a 20" wheel (406) for a folding bike.

Here's a closeup of a small section: http://www.ncf.ca/~af895/bikes/rim.jpg
....and a larger section: http://www.ncf.ca/~af895/bikes/rim2.jpg


> What is their inside width?


I measured outside width of the rims (braking surface to braking surface)
and it's an inch. Presumably inside width is slightly less. If the inside
measurement is needed to determine if the new tire will fit, I'll remove the
tire and measure.


> What condition is the rim in?


"As new."


> What pressure will you inflate the tire to?


60-100psi. (depending on tire)

The Schwalbe Marathon slicks appear to be wire bead - which I'm told will be
a bit better at staying in place than a kevlar bead.

Thanks,
Chris
 

daveornee

New Member
Sep 18, 2003
2,763
0
0
C.J.Patten said:
"daveornee" <[email protected]> wrote in
message news:[email protected]

> What model rim?


I don't have a model number but it's an aluminum rim, 32-spoke, conventional
brake, clincher and, as mentioned, a 20" wheel (406) for a folding bike.

Here's a closeup of a small section: http://www.ncf.ca/~af895/bikes/rim.jpg
....and a larger section: http://www.ncf.ca/~af895/bikes/rim2.jpg


> What is their inside width?


I measured outside width of the rims (braking surface to braking surface)
and it's an inch. Presumably inside width is slightly less. If the inside
measurement is needed to determine if the new tire will fit, I'll remove the
tire and measure.


> What condition is the rim in?


"As new."


> What pressure will you inflate the tire to?


60-100psi. (depending on tire)

The Schwalbe Marathon slicks appear to be wire bead - which I'm told will be
a bit better at staying in place than a kevlar bead.

Thanks,
Chris
You should be fine with the Scwalbe 1.35"
Take a look at the chart at URL:
http://sheldonbrown.com/tire-sizing.html#width
Note: The chart uses inside measurement.
 
Z

Zog The Undeniable

Guest
C.J.Patten wrote:

> Howdy folks.
>
> Thinking of putting narrow tires on my 20" rims (406's - folding bike).
> They came with 1.95 knobby tires, I'm down to 1.50 slicks.
>
> I measured the rim width and it's 1 inch. I'd like to put Schwalbe Marathon
> slicks on which are 20x1.35's.
>
> Can I get away with this without worrying about them popping off? (or just
> popping)


Yes, provided they are hook bead rims (most are). The *optimum* tyre
width is around 1.5 X rim width for the best round profile without too
much rim stress or chafing.