I am watching the online IM lake placid coverage and what an amount of exploding tyres and the guy is fixing them very quick.
Good work from the volunteers to listen to explosions.
It always amazes me people pump their tires up so much that the heat of the sun will make them explode… Obviously, they don’t hang out on ST and know anything over 120 psi is unnecessary and actually could be slower over all.
This was pretty rampant at last year’s Timberman too, as there was a pretty big difference between pre-race and race temperatures. Not so much exploding in T1, but lots on the course. I’d much rather have my tires a bit under pressure than so far over that they explode.
Too many people put on new tires the day of registration…and never ride them before the race. A buddy of mine did this at IMFL a couple years back, and his tire blew the second he hopped on it exiting T1. He blamed overpressure…I’m sure he pinched the tube installing it. If yer at 120psi it isn’t going to hit exploding range (140+) by the end of the swim…
A lot of people are using aero wheels (borrowed, rented, theirs) that aren’t used to the valve extenders and how to tell how much air they are really putting in the tube. BOOM!
For what it’s worth, in the 1st or 2nd year I was racing, I had a guy at the expo at Mrs. T’s tell me I should never race below 135psi. People dispense all kinds of advice.
Of course, in the process of pumping up my tires for me (I couldn’t find my valve extenders) he popped my inner tube, so…
i’ll bite. how much psi in disc / other aero tires? and how much psi in training/ regular rides, tires? new to the forum, haven’t been part of the debates…sorry in advance
Research has show that, unless you’re on a very, very smooth surface (e.g., a track), anything above 120 psi is slower. The problem is that above 120 tires are “bouncier” and energy is lost vertically. This holds for training and racing, of course.
thanks, very interesting. learn something new every day. any links to the research based data? i’ll get hammered with that info where i’m from, or should i just keep it to my…???
I assume that you are talking about clinchers and not tubulars. Check the website for your tire manufacturer’s recommendation. For instance, for Zipp Tangente tires, it would vary between 103 to 130 psi depending the circumstance. Your weight, type of event, front/rear tire and weather conditions would vary the recommended tire pressure.
Research hasn’t shown that except for maybe 1 particular tire at one particular rider weight
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A lot of people are using aero wheels (borrowed, rented, theirs) that aren’t used to the valve extenders and how to tell how much air they are really putting in the tube. BOOM!
So we have a whole lot of people just pumping air into tires/tubes without any sort of gauge or even a simple thumb test? I find that very hard to believe.
Lennard Zinn did a column a while back:
http://www.velonews.com/tech/report/articles/7508.0.html
And I’ll give you a link to a prior ST thread, which indicates some difference of opinion, as jackmott has already indicated.
http://forum.slowtwitch.com/gforum.cgi?do=post_view_flat;post=1321820;page=1;sb=post_latest_reply;so=ASC;mh=25;
Too many people put on new tires the day of registration…and never ride them before the race. A buddy of mine did this at IMFL a couple years back, and his tire blew the second he hopped on it exiting T1. He blamed overpressure…I’m sure he pinched the tube installing it. If yer at 120psi it isn’t going to hit exploding range (140+) by the end of the swim…
Exactly… I agree that they’re probably getting snake bites when the pressure builds, not exceeding the tire’s PSI capacity…
I thought all the studies suggest LOWER tire pressure is actually less rolling resitance. I think people get nervous/obsessive and over inflate.
well, to hang out on slowtwich, you might also listen to people that says tire pressure goes up to blow up a tire because of the sun!!! that is so untrue. It would take a crazy hot amount of temperature for this to happen and it s never hot enough on Earth for this to happen…
pressure will go up if you have a alu rim and you go down a very technical dowhill with tons of breaking, the rim temp will go up and the pressure in the tire will also but most likely not enough to blow a tire either…
tire blow because people pinch them most of the time… like a previous slowtwicher said, people put new tube in there wheels and pinch them…simple…not much to do with pressure and it s not necessary to deflate your tire the day before a race because of the hot temperature…wont blow up a tire…
sorry for crashing this thread but I am hoping someone can tell me where to go at IMLP tomorrow to sign up for next years race. i don’t want to miss out by signing up online and getting stumped.
And just to keep the thread alive here is my addition. the tires I am running are Vittora Diamente Lite and the listed pressure starts at 130psi. I always stop there because it seems so insanely high but I think they go to 160!!! why on earth do they need to be so high?
I think you go right up to the school behind the Transition area, they have computers set up there. (I think)
thanks for the info. I figure I should go where there are 700 plus people lining up. haha but it would be nice to know exactly since I will be racing into town at 8:30 tomorrow morning.
Usually at the horse show grounds where all the meals are.