Panaracer Col de Vie tire inflation

[Zaelia]

My last pair of Panaracer Col de Vie tires said "keep inflate to 50
lbs" [sic]. I often inflated them to roughly 60 psi (with a little
more air in the back tire). One mechanic noted on a sales receipt " 65
psi (overrating) at client request". I cannot recall where, but I read
somewhere that people were inflating their tires in this range.

I had these tires for over a year and roughly 2500 km (1553 miles) and
didn't have any known issues. A friend was the one to suggest it was
time to get new tires after looking at the sidewalls and noting some
striation. Could over inflating shorten the life of these tires?

My new tires have Japanese writing on the sidewall (very helpful) and
"300kPa (30kgf/cm2). Google calculated for me that 300 kPa is
43.5113213 pounds per square inch, so this is roughly what I inflated
the new tires to.

So, I'm wondering
* could over inflating shorten the life of these tires?
* why the two different pressures for the same tires?
* what do other Panaracer Col de Vie users inflate their tires to?

Finally, when I bought the first pair, I bought a spare because I was
led to believe it would be so difficult to get 650B tires. It has been
hanging in a dark closet. What is the life of a tire kept like this?
The next time I get new tires, should I use this spare and hang a new
spare?

Thanks

[cyclotourist]

Hi Zaelia, tire pressure is dynamic, and should be based on the rider/bike weight as well as the width of the tire and riding conditions.  No one pressure is best.  Bicycle Quarterly made a cool little calculator that Philip updated and Jim posted here (oops, may not work anymore, thanks Google).  I use it and have been VERY satisfied with it's recommendations.  FWIW, my total weight (me + bike) was 200lbs and I ran CdlVs 60 back, 35 front.  Never a pinch flat.

http://www.biketinker.com/tire-pressure-calculator/

http://www.biketinker.com/2010/bike-resources/optimal-tire-pressure-for-bicycles/

--
You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group.
To post to this group, send email to rbw-owne...@googlegroups.com.
To unsubscribe from this group, send email to rbw-owners-bun...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.

--
Cheers,
David
Redlands, CA

...in terms of recreational cycling there are many riders who would probably benefit more from
improving their taste than from improving their performance. - RTMS

[Johnny Alien]

I don't know if it will hurt them but running them that high will defeat some of the comfort level that the fatter tires deliver. I think I always kept my Col de Vies at around 45psi.

[Zaelia]

"Bicycle Quarterly made a cool little calculator that Philip updated and Jim posted"

Thank you for reminding me about this. I had seen it before (and saved a copy in my computer files). The numbers I get seem pretty low to me (34 rear, 20 front). It might help if I understood it a little more. Numbers have never been my strong suit though.

[Zaelia]

I don't know if it will hurt them but running them that high will defeat some of the comfort level that the fatter tires deliver.

I did experiment with pressure in the past and found I was more comfortable with the higher pressure. That said, I have taken the bike on a few rides with the new tires and lower pressure, and I have not felt like I wanted to change anything...

[cyclotourist]

Did you include your weight + the bike's weight?  If you didn't, just add 25-30lbs to your weight and put the # in.  I ran the numbers and to get that pressure would have to weigh 100# and have a 25# bike for a total of 125#.  If that's your weight, then try it and see how it feels that low.  If you don't like it that low, then you really don't need tires that wide and could try some narrower ones like the Maxy Fasty.  Have fun experimenting!

On Sun, Aug 7, 2011 at 6:01 PM, Zaelia <cadd...@gmail.com> wrote:

"Bicycle Quarterly made a cool little calculator that Philip updated and Jim posted"

Thank you for reminding me about this. I had seen it before (and saved a copy in my computer files). The numbers I get seem pretty low to me (34 rear, 20 front). It might help if I understood it a little more. Numbers have never been my strong suit though.

--

You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group.

To view this discussion on the web visit https://groups.google.com/d/msg/rbw-owners-bunch/-/N3Tmq0GdX4YJ.

To post to this group, send email to rbw-owne...@googlegroups.com.
To unsubscribe from this group, send email to rbw-owners-bun...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.

[Steve Palincsar]

On Sun, 2011-08-07 at 18:45 -0700, cyclotourist wrote:
> Did you include your weight + the bike's weight? If you didn't, just
> add 25-30lbs to your weight and put the # in. I ran the numbers and
> to get that pressure would have to weigh 100# and have a 25# bike for
> a total of 125#. If that's your weight, then try it and see how it
> feels that low. If you don't like it that low, then you really don't
> need tires that wide and could try some narrower ones like the Maxy
> Fasty. Have fun experimenting!

But remember that the BQ chart is weight per wheel, not total weight.

[cyclotourist]

The spreadsheet I was looking at uses total weight, then divides it 60/40...

--
You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group.

To post to this group, send email to rbw-owne...@googlegroups.com.
To unsubscribe from this group, send email to rbw-owners-bun...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.

[Zaelia]

I need to read things more carefully. Initially, I only put down my weight. I don't know exactly what my bike weighs, so I added 30 and then added another 20 for gear. This changed the numbers to 49 rear and 30 front. Thanks for pointing that out to me. 

I'm still curious about the other things as well, if anyone has any insight.

   * could over inflating shorten the life of these tires? 
   * why the two different pressures for the same tires? 

Finally, when I bought the first pair, I bought a spare because I was 
led to believe it would be so difficult to get 650B tires. It has been 
hanging in a dark closet. What is the life of a tire kept like this? 
The next time I get new tires, should I use this spare and hang a new 
spare? 

Thanks

[cyclotourist]

Gladly.  The differences in pressure are based on the average bicycle bearing 60% of the weight on the rear tire.  This is why rear tires wear faster and rear wheels are often built stronger.  The extra weight means the tire needs to be run at a higher pressure.  In the spreadsheet you can change the percentages, but 60/40 is pretty accurate. 

As long as there is not an ozone source in the closet (usually generated from electric motors like in a refrigerator) the tire in the closet should last a long time.  When you are ready to mount it, look it over carefully for cracks.  Fine surface cracks are not a problem, but large ones going through the rubber and to the casing are a concern.  If you wanted to put it in a plastic bag, like a trash bag, that might protect it even more.  That's probably not necessary though.  It doesn't hurt to have a spare on hand.

Hope that answered a few questions :-)

--

You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group.

To view this discussion on the web visit https://groups.google.com/d/msg/rbw-owners-bunch/-/0IheADDnKXQJ.

To post to this group, send email to rbw-owne...@googlegroups.com.
To unsubscribe from this group, send email to rbw-owners-bun...@googlegroups.com.
For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en.

[Zaelia]

Thank you for the explanation on the differences in pressure for the tires mounted on the bicycle. My question was actually about the two different pressures listed on the two sets of tires from the same manufacturer... My first set, purchased over a year ago said "keep inflate to 50 lbs" [sic]. My new tires  have the following listed on the side - "300kPa (30kgf/cm2) [43.5113213 pounds per square inch]. I know it's not a big difference, but I was just curious if anyone knew why they are different.

Thank you for the information on the spare tire. This is really helpful.