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Zilla

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Thanks to all I have the 37-597 tires on my
Schwinn now. However I noticed on the rear
wheel, a portion of the tire gets "oblonged"
when properly inflated. I take the tire and
tube off, put the wheel on a truing stand, and
the wheel itself is "pretty true". So this means
it's NOT the wheel. I put back the tube/tire
back on, inflate, and I get the same "non-
roundness" on the tire. I see the tire fluctuate
to 1/4"-3/8" from roundness when observing
it with a guide. It's almost as if the tire "goes
further" in this part of the wheel". This is near
the valve.

To explain it a different way, if one looks at
the wheel and tire as 2 concentric circles, with
the wheel being the inner circle, one would
expect the their two circumferences to be
equidistant throughout, correct? Well in my
case, the outter circle goes "non-uniform"
in one part; hence the circumferences are
non-equidistant in that part.

--
- Zilla
Cary, NC USA
(Remove XSPAM)
 
Zilla wrote:
> Thanks to all I have the 37-597 tires on my
> Schwinn now. However I noticed on the rear
> wheel, a portion of the tire gets "oblonged"
> when properly inflated.


You mention that the problem area is near the valve which makes me
suspect that perhaps that portion of the tube is getting pinched under
the bead of the tire. That prevents the bead from seating properly in
the rim and therefore results in the tire sitting out farther in that
area.

Before inflating the tube you should push in on the valve to make sure
that it freely goes into the interior of the tire and isn't being hung
up under the bead.
 
peter wrote:
> Zilla wrote:
> > Thanks to all I have the 37-597 tires on my
> > Schwinn now. However I noticed on the rear
> > wheel, a portion of the tire gets "oblonged"
> > when properly inflated.

>
> You mention that the problem area is near the valve which makes me
> suspect that perhaps that portion of the tube is getting pinched under
> the bead of the tire. That prevents the bead from seating properly in
> the rim and therefore results in the tire sitting out farther in that
> area.
>
> Before inflating the tube you should push in on the valve to make sure
> that it freely goes into the interior of the tire and isn't being hung
> up under the bead.


Peter's description is pretty close.

IIRC, getting tires to seat properly on the old S-6 rims was pretty
easy with Schwinn-brand tires but a hit-or-miss proposition with
off-brand tires. There's a couple hints for correcting this at
http://www.bikewebsite.com/bike-tiretube.htm

Jeff
 
Seating may very well be the issue, but keep in mind, that sometimes
you can get amazingly **** tires, especially those "vintage" sizes.
I've run into a couple situations, one very similar to yours, where I
was about to true the wheel vertically, something which I *hate* doing
(as I suck at it) only to see after careful observation, that it was a
poorly manufactured tire doing the bobbing.
 
Zilla wrote:
> Thanks to all I have the 37-597 tires on my
> Schwinn now. However I noticed on the rear
> wheel, a portion of the tire gets "oblonged"
> when properly inflated. I take the tire and
> tube off, put the wheel on a truing stand, and
> the wheel itself is "pretty true". So this means
> it's NOT the wheel. I put back the tube/tire
> back on, inflate, and I get the same "non-
> roundness" on the tire. I see the tire fluctuate
> to 1/4"-3/8" from roundness when observing
> it with a guide. It's almost as if the tire "goes
> further" in this part of the wheel". This is near
> the valve.
>
> To explain it a different way, if one looks at
> the wheel and tire as 2 concentric circles, with
> the wheel being the inner circle, one would
> expect the their two circumferences to be
> equidistant throughout, correct? Well in my
> case, the outter circle goes "non-uniform"
> in one part; hence the circumferences are
> non-equidistant in that part.
>


I'm not sure why, but I've had some problems getting tires to seat
evenly on some rims. I've used a bit of liquid soap and temporary over
pressure to persuade things to go on straight.
 
On Sat, 06 May 2006 13:18:09 -0400, Peter Cole
<[email protected]> wrote:

>Zilla wrote:
>> Thanks to all I have the 37-597 tires on my
>> Schwinn now. However I noticed on the rear
>> wheel, a portion of the tire gets "oblonged"
>> when properly inflated. I take the tire and
>> tube off, put the wheel on a truing stand, and
>> the wheel itself is "pretty true". So this means
>> it's NOT the wheel. I put back the tube/tire
>> back on, inflate, and I get the same "non-
>> roundness" on the tire. I see the tire fluctuate
>> to 1/4"-3/8" from roundness when observing
>> it with a guide. It's almost as if the tire "goes
>> further" in this part of the wheel". This is near
>> the valve.
>>
>> To explain it a different way, if one looks at
>> the wheel and tire as 2 concentric circles, with
>> the wheel being the inner circle, one would
>> expect the their two circumferences to be
>> equidistant throughout, correct? Well in my
>> case, the outter circle goes "non-uniform"
>> in one part; hence the circumferences are
>> non-equidistant in that part.
>>

>
> I'm not sure why, but I've had some problems getting tires to seat
>evenly on some rims. I've used a bit of liquid soap and temporary over
>pressure to persuade things to go on straight.


Dear Peter,

Sometimes the stupid sidewalls just stick against the rim.

Soap and over-pressure help, but can be hard to come by in
the field.

Another trick is to inflate the stubborn tire lightly and
then use both thumbs to push in repeatedly where the
sidewall is playing coy. The sidewall will often lose its
shyness and emerge.

Cheers,

Carl Fogel
 
[email protected] wrote:
> On Sat, 06 May 2006 13:18:09 -0400, Peter Cole
> <[email protected]> wrote:
>
>> Zilla wrote:
>>> Thanks to all I have the 37-597 tires on my
>>> Schwinn now. However I noticed on the rear
>>> wheel, a portion of the tire gets "oblonged"
>>> when properly inflated. I take the tire and
>>> tube off, put the wheel on a truing stand, and
>>> the wheel itself is "pretty true". So this means
>>> it's NOT the wheel. I put back the tube/tire
>>> back on, inflate, and I get the same "non-
>>> roundness" on the tire. I see the tire fluctuate
>>> to 1/4"-3/8" from roundness when observing
>>> it with a guide. It's almost as if the tire "goes
>>> further" in this part of the wheel". This is near
>>> the valve.
>>>
>>> To explain it a different way, if one looks at
>>> the wheel and tire as 2 concentric circles, with
>>> the wheel being the inner circle, one would
>>> expect the their two circumferences to be
>>> equidistant throughout, correct? Well in my
>>> case, the outter circle goes "non-uniform"
>>> in one part; hence the circumferences are
>>> non-equidistant in that part.
>>>

>> I'm not sure why, but I've had some problems getting tires to seat
>> evenly on some rims. I've used a bit of liquid soap and temporary over
>> pressure to persuade things to go on straight.

>
> Dear Peter,
>
> Sometimes the stupid sidewalls just stick against the rim.
>
> Soap and over-pressure help, but can be hard to come by in
> the field.


No, but you needn't have a tire perfectly mounted to get home.


> Another trick is to inflate the stubborn tire lightly and
> then use both thumbs to push in repeatedly where the
> sidewall is playing coy. The sidewall will often lose its
> shyness and emerge.


Perhaps, but I can attest to some that have stubbornly resisted that
(the default) method of seating tires.
 
[email protected] wrote:
> On Sat, 06 May 2006 13:18:09 -0400, Peter Cole
> <[email protected]> wrote:
>
> >Zilla wrote:
> >> Thanks to all I have the 37-597 tires on my
> >> Schwinn now. However I noticed on the rear
> >> wheel, a portion of the tire gets "oblonged"
> >> when properly inflated. I take the tire and
> >> tube off, put the wheel on a truing stand, and
> >> the wheel itself is "pretty true". So this means
> >> it's NOT the wheel. I put back the tube/tire
> >> back on, inflate, and I get the same "non-
> >> roundness" on the tire. I see the tire fluctuate
> >> to 1/4"-3/8" from roundness when observing
> >> it with a guide. It's almost as if the tire "goes
> >> further" in this part of the wheel". This is near
> >> the valve.
> >>
> >> To explain it a different way, if one looks at
> >> the wheel and tire as 2 concentric circles, with
> >> the wheel being the inner circle, one would
> >> expect the their two circumferences to be
> >> equidistant throughout, correct? Well in my
> >> case, the outter circle goes "non-uniform"
> >> in one part; hence the circumferences are
> >> non-equidistant in that part.
> >>

> >
> > I'm not sure why, but I've had some problems getting tires to seat
> >evenly on some rims. I've used a bit of liquid soap and temporary over
> >pressure to persuade things to go on straight.

>
> Dear Peter,
>
> Sometimes the stupid sidewalls just stick against the rim.
>
> Soap and over-pressure help, but can be hard to come by in
> the field.
>
> Another trick is to inflate the stubborn tire lightly and
> then use both thumbs to push in repeatedly where the
> sidewall is playing coy.


I like to use the palms of my hands as I hate sore "tire thumbs". ;-)
 
<[email protected]> wrote in message
news:[email protected]...
> On Sat, 06 May 2006 13:18:09 -0400, Peter Cole
> <[email protected]> wrote:
>
> >Zilla wrote:
> >> Thanks to all I have the 37-597 tires on my
> >> Schwinn now. However I noticed on the rear
> >> wheel, a portion of the tire gets "oblonged"
> >> when properly inflated. I take the tire and
> >> tube off, put the wheel on a truing stand, and
> >> the wheel itself is "pretty true". So this means
> >> it's NOT the wheel. I put back the tube/tire
> >> back on, inflate, and I get the same "non-
> >> roundness" on the tire. I see the tire fluctuate
> >> to 1/4"-3/8" from roundness when observing
> >> it with a guide. It's almost as if the tire "goes
> >> further" in this part of the wheel". This is near
> >> the valve.
> >>
> >> To explain it a different way, if one looks at
> >> the wheel and tire as 2 concentric circles, with
> >> the wheel being the inner circle, one would
> >> expect the their two circumferences to be
> >> equidistant throughout, correct? Well in my
> >> case, the outter circle goes "non-uniform"
> >> in one part; hence the circumferences are
> >> non-equidistant in that part.
> >>

> >
> > I'm not sure why, but I've had some problems getting tires to seat
> >evenly on some rims. I've used a bit of liquid soap and temporary over
> >pressure to persuade things to go on straight.

>
> Dear Peter,
>
> Sometimes the stupid sidewalls just stick against the rim.
>
> Soap and over-pressure help, but can be hard to come by in
> the field.
>
> Another trick is to inflate the stubborn tire lightly and
> then use both thumbs to push in repeatedly where the
> sidewall is playing coy. The sidewall will often lose its
> shyness and emerge.
>
> Cheers,
>
> Carl Fogel


I tried this last night to no avail. I'll try the overinflate
method.

--
- Zilla
Cary, NC USA
(Remove XSPAM)