Nice places for visits from the fairy

secretsam · May 2015

Got a visit from the little minx this morning, whilst coming through Trafalgar Square! Changed the tube leaning up against that model of Gromet done up as Nelson :twisted:

Then the damn minipump wouldn't do its thing :evil: , so had to walk to Cyclesurgery and borrow their track pump (thanks, guys)

Anyone beat that for a tourist-tastic location?

lostboysaint · May 2015

Mine was on a road/track about 10km north of Sao Bartholomeu, in amongst the lakes and rivers, in 40degC heat and was a split sidewall.

Fortunately my riding companion was a smoker so with the lid of his censored packet folded over covering the split and a new tube gassed up I was able to ride the 35km back home without an issue (and the rest of the holiday's riding!).

bompington · May 2015

I only cycle in nice places, so anywhere I've ever changed a puncture has been pleasant - at least scenery wise.
But here (I'm not one of the guys in the street view!) was no fun in a blizzard with inches of snow on the road one dark January night.
Here, on the other hand, was great, possibly due to the adrenaline of surviving a front tyre blow out at exactly 50mph (like a lot of street view pics, you don't really see the gradient) - without coming off or any damage beyond a bust tyre and a lightly dented rim.

pblakeney · May 2015

On the balcony of my apartment in Port Pollensa in the sunshine.

I simply got a bottle of lager from the fridge to cool down whilst changing tubes.

I cannot imagine a much more pleasant visit.

secretsam · May 2015

pblakeney wrote:

On the balcony of my apartment in Port Pollensa in the sunshine.

I simply got a bottle of lager from the fridge to cool down whilst changing tubes.

I cannot imagine a much more pleasant visit.

how on earth did you flat in an apartment?

bompington · May 2015

Well, when we were in PP we stayed in a flat...

itboffin · May 2015

Outside the roebuck at one of the summer drinks, beer & a nice view

Meh

veronese68 · May 2015

itboffin wrote:

Outside the roebuck at one of the summer drinks, beer & a nice view

Meh

I once had the headlamp wiring in a car catch fire outside the Roebuck. Put the fire out and went for a few pints to calm my nerves. Well I couldn't drive it home could I.

tgotb · May 2015

I managed to get a puncture on the turbo; I haven't the faintest idea how!

pblakeney · May 2015

secretsam wrote:

pblakeney wrote:

On the balcony of my apartment in Port Pollensa in the sunshine.

I simply got a bottle of lager from the fridge to cool down whilst changing tubes.

I cannot imagine a much more pleasant visit.

how on earth did you flat in an apartment?

Blow up the tyres to full pressure in a cool air conditioned room.
Move bike onto balcony in full sunshine and alloy rims.
Temperature increases, pressure increases, boom!

Also happened to someone in another group outside a cafe in Petra.

Lesson learned.

redvee · May 2015

secretsam wrote:

Got a visit from the little minx this morning, whilst coming through Trafalgar Square! Changed the tube leaning up against that model of Gromet done up as Nelson :twisted:

This Grommit??

10.%20Nelson.JPG?_subject_uid=28986481&w=AABiRiBoWPv4L4-4XePmBCCELMuWcLReyhRW7haiX5i7dg

FoldingJoe · May 2015

here

Punctured up the climb so thought I'd change it at the top and enjoy the view.

The Rookie · May 2015

pblakeney wrote:

secretsam wrote:

pblakeney wrote:

On the balcony of my apartment in Port Pollensa in the sunshine.

I simply got a bottle of lager from the fridge to cool down whilst changing tubes.

I cannot imagine a much more pleasant visit.

how on earth did you flat in an apartment?

Blow up the tyres to full pressure in a cool air conditioned room.
Move bike onto balcony in full sunshine and alloy rims.
Temperature increases, pressure increases, boom!

Also happened to someone in another group outside a cafe in Petra.

Lesson learned.

Doesn't actually stack up, say 20C inside to getting it to 60C outside that is less than a 15% increase in pressure even allowing for no stretch of the tyre!

pblakeney · May 2015

The Rookie wrote:

pblakeney wrote:

secretsam wrote:

pblakeney wrote:

On the balcony of my apartment in Port Pollensa in the sunshine.

I simply got a bottle of lager from the fridge to cool down whilst changing tubes.

I cannot imagine a much more pleasant visit.

how on earth did you flat in an apartment?

Blow up the tyres to full pressure in a cool air conditioned room.
Move bike onto balcony in full sunshine and alloy rims.
Temperature increases, pressure increases, boom!

Also happened to someone in another group outside a cafe in Petra.

Lesson learned.

Doesn't actually stack up, say 20C inside to getting it to 60C outside that is less than a 15% increase in pressure even allowing for no stretch of the tyre!

Fine.
You do the maths.
Still happened. And it was 16C inside. I like it cool when sleeping.

The Rookie · May 2015

So another 2%, still doesn't stack up as the cause.

tgotb · May 2015

pblakeney wrote:

The Rookie wrote:

pblakeney wrote:

secretsam wrote:

pblakeney wrote:

On the balcony of my apartment in Port Pollensa in the sunshine.

I simply got a bottle of lager from the fridge to cool down whilst changing tubes.

I cannot imagine a much more pleasant visit.

how on earth did you flat in an apartment?

Blow up the tyres to full pressure in a cool air conditioned room.
Move bike onto balcony in full sunshine and alloy rims.
Temperature increases, pressure increases, boom!

Also happened to someone in another group outside a cafe in Petra.

Lesson learned.

Doesn't actually stack up, say 20C inside to getting it to 60C outside that is less than a 15% increase in pressure even allowing for no stretch of the tyre!

Fine.
You do the maths.
Still happened. And it was 16C inside. I like it cool when sleeping.

Maths stacks up; 40 degree increase will cause an increase of 15%, which you'd have thought was well within tolerance. However I did almost the same thing many years ago; inflated the tyre outside, subsequently brought the bike indoors and sat it behind the sofa, and got the fright of my life when it exploded while I was watching TV. That would have been a 20 degree increase, at most. I did the same thing this Winter, putting a CX tyre inflated to ~20psi in the car and then turning the heating on, *but* that already had a very big bulge in the sidewall.

You're both right :-)

As a complete aside, the maths says that sticking your bike in an aeroplane will result in ~5psi increase at altitude, so you really don't need to deflate your tyres before taking your bike on holiday. Even taking them into space (+14psi) would be pretty unlikely to blow them off the rims.

Edit: Is 60 degrees a realistic temperature for a black tyre left in hot sun? I don't know for sure, but it wouldn't surprise me if it got a lot hotter than that (thinking of anecdotal tales of people frying eggs on car bonnets).

The Rookie · May 2015

I used 60 based on the internal temperature of a dark car parked in midday sunshine in Seville in July. Was testing for a car manufacturer at the time.

You need a very high solar load on matt black absorber to do that, so something like death valley, you won't get that intensity unless the sun is near enough directly overhead as a small change in angle has a significant effect on the amount of radiation absorbed in the atmosphere.

tgotb · May 2015

The Rookie wrote:

I used 60 based on the internal temperature of a dark car parked in midday sunshine in Seville in July. Was testing for a car manufacturer at the time.

You need a very high solar load on matt black absorber to do that, so something like death valley, you won't get that intensity unless the sun is near enough directly overhead as a small change in angle has a significant effect on the amount of radiation absorbed in the atmosphere.

In that case, given that it clearly happened, one of your other assumptions must be wrong :-)

The Rookie · May 2015

Or the setup was defective and about to go pop anyway, as that does happen without any external influence at all (had it just like that about 4 weeks ago, no sun, no heat, just pumped it up and came back 20 minutes later and the tyre was blown off the rim.

Nice places for visits from the fairy

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