Pacers Sunday 18th January

[xrayspecs]

Met up with Andrew Storrie, Chris Reed, Haydn , Mark R and Ben at Talbot Green after a fairly dicey ride from the Vale. Mark R had already been on the deck once no harm done. Proceeded via Llantrisant St Fagans (where someone was being loaded into an ambulance ?cyclist) Barry and Rhoose to Cafe Velo. Back out of Llantwit not quite sure what happened as it was behind me but someone must have dreamt they were in Ben Hur. A fairly dramatic loud ticking sound of metal on metal. End result was Mark Rossers wheel had shredded spokes and he had to call out the team support vehicle.
Probably a day to stay in.

[Tom]

Ouch-my timidity seems justified for once.I met Andy S just outside Llantwit and we rode back along the main road to St Brides-fortunately neither of us came off in that distance!

[harpo]

The crash was nothing to do with the weather! good ride apart from that incident

[wardhaugh]

I was on my way to join you, and got as far as the end of my drive where a passing motorist stopped and advised I go no further - black ice all over M4 bridge, and he'd seen one cyclist fall off and two cars lose control on his short journey. I took his advice and watched the episode of Spiral I'd missed last night. Went out ice-free for a short spin this afternoon. Looks like weather could be a problem for cycle-commuting this week 

[Shawn]

Yellow ice warning for tonight and tomorrow morning. Definitely a day to take the car.

Not sure if the temperature may have kept going down this morning. I was out early and roads were OK through Pontyclun and out to Cowbridge. From St. Athan on things got decidedly more dicey

[Rob Jones]

Ice is more slippery as it melts.

[Tom]

That's an interesting comment Rob.Is there any scientific basis for that(over to you Engineers Rob Powell)

[Rob Jones]

Well both times its got me off its been melting Tom. I figure riding on water with ice underneath you've got no chance!

[Tom]

When we had to investigate slipping accidents I recall engineering experts used some sort of formula for the co-efficient of slipperiness.I don't know if water is more slippery than ice though

[Terry A]

The 'slipperiness' of ice changes with temperature. Ice has a thin layer of water on top - it's the water layer that makes it slippery. This ultra thin water layer is thickest when the ice temp is just below freezing and becomes a much thinner layer when the temp falls well below freezing. A bit weird, but this is why really cold ice is less slippery than ice which is not so cold.
Even really cold ice has a vapour pressure due to surface liquid - even if not to the touch or visible.

[Tom]

Thanks Terry,that's a very comprehensive response-what an erudite club we are!Actually when I read that it did start to stir a few long-forgotten memories of reading Engineers' Repors.On that basis on a really cold day we'd be better off not waiting for it to warm up and melt(a bit) but go out early on!I don't think so-staying in bed is the wisest option!
Thankfully no ice in Mallorca

[Rob Jones]

Ice is less slippery in the dark

[xrayspecs]

By the time I went over the M4 bridge at 1015 in Pontyclun it had had the sun on it but still looked bad ; the trouble was I didn't want to touch my brakes so had to sail down at 25 mph waiting for the wheels to go.
So what have I learnt from all this? I know of at least 8 riders and 4 cars which crashed now.
If there is a yellow warning of ice best to stay home / turbo /rollers. Ice on the side roads= ice on the main roads as you are just hoping they have been gritted and no bits are missing.
I am just as daft as everyone else in my pursuit of a weekly fix after being on the turbo all week despite usually being fairly cautious!