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Zipp clincher warping problems(22 posts)

Zipp clincher warping problemsweiwentg
Oct 13, 2002 9:59 AM
some guy who goes by gimondi posted this on the Velonews forum:
http://www.velonews.com/phorum/read.php?f=1&i=50767&t=50720

Just got back from Interbike, spent about an hour with the Zipp engineer looking at their insane new product. Also have a customer with a 'flaring' pair of 303 clinchers and got that story as well.

The aluminum in the clincher weighs about 175-180 grams. A typical aluminum rim weighs about 475-600. An average guy descending and using the brakes will put the same amount of energy into the rim regardless of rim weight. However, rim temperature equals energy input, divided by mass, minus air cooling effects. Since the rim is about a third the weight, it can get about three times as hot. Zipp said that Mapei had 60 pair of prototypes before product release, and never a failure. Also, multiple pro teams in the US are using them without problems. But the factors are as follows: the pros brake hard and fast, then corner and finish descending. The pros use the recommended tire pressure which is never above 125psi. The rest of us white knuckle the brakes for the whole descent, never giving the rim time to cool off, we also run high tire pressures...Interesting story, Tom Ritchey was in the booth talking to the Zipp guys, who were asking why his new tire is rated up to 190psi, when all the data shows it has much lower rolling resistance at 120? Tom says: the consumer equates high psi with speed and performance, so we are giving it to them. True story.

Anyway, at 165psi, braking for 1 minute on a long downhill can increase rim temperature to 225psi or higher as rim temperatures approach 450F. This causes the carbon/epoxy to soften, the aluminum to weaken, and the high pressure forces the aluminum beads apart. The Zipp guys seem a bit frustrated in telling me that they passed every DIN test, ISO test, and were rated tops by Tour magazine in every category, as well as performing R&D with major teams and athletes in various climates around the world in the design of this rim. What they didn't anticipate was how the average guy rides. The other problem is the Campy brake pad. They told me that over 75% of the rims with this problem are on Campy equipped bikes, as Campy adds aluminium oxide to the brake pads for increased friction, eg increased heat.

They have developed a new thermally conductive brake pad to help this. Other than that, I guess just don't ride the brakes so much.

ps, I ride 404 tubulars and with over 6000 miles on Colorado roads with nary a problem I am quite satisfied. But I hate clinchers, always have.
I heard about a guy bending one on a jump in China....IAmtnbikr
Oct 13, 2002 11:41 AM
NM
(sigh)weiwentg
Oct 13, 2002 3:36 PM
perhaps someday someone will make a joke about something stupid you did that got you injured or killed. I hope not, though.
yeah, I know....but if I did do something REALLY STUPIDIAmtnbikr
Oct 14, 2002 9:12 AM
and by stupid I mean not analyzing the risks involved, then by all means I should deserve a Darwin Award. I drag raced for years, eventually running 200+ in a supercharged alcohol funny car. I guess had I been injured or killed, it was not an act of stupidity, as I did realize the risks, and still chose to do it. However, I did have the BEST safety equipment money could buy, and always used my head when driving, knowing it was a better choice at times to lift and give up on a run than to stick it in the wall. There is a difference in being stupid, or doing something dangerous and taking a risk, but it sure is a fine line.
Hey, come down off the cross - we could use the wood. - nmgrzy
Oct 14, 2002 2:00 PM
uh, heh heh, heh heh, he said wood ! NMIAmtnbikr
Oct 14, 2002 3:08 PM
NM
off topicweiwentg
Oct 14, 2002 7:09 PM
grzy, I don't know exactly what your problem is. it's obvious you have issues, and severe ones at that. if I had to wager, I would probably say that you are from a culture of insecure masculinity which has to prove itself by insulting anyone who doesn't conform to it.
I'm very sorry I responded to you the way I did in my post on General - you're too pathetic to deserve an insult in return. I regret getting all worked up over that, because it colored the rest of my responses. if that was what you intended, I congratulate you; you're pathetic but at least you're cunning. if not, you're just pathetic, and either way, I pity you.
Thank Yougrzy
Oct 16, 2002 2:07 PM
Yes, I got your goat and that was my objective. Goat soup coming up!

My problem is you, only you're too much of a simpleton to realize it so I have to spell it out for you.

Actually, all I really wanted you to do was come down off your high horse, and stop preaching your pseudo morality and tripe to the rest of us. You're entitled to your opinion, but you're not entitled to tell us what we can or can not write or think. If you don't like what people write then leave or at least join the GOP. No one left you in charge. You're pissing against the wind and you're just going to wind up wet and smelly in this free-for-all we call the 'net.

If you act like a child you're going to get ridiculed until you either grow up or fade away. If you can't see some humor in some retard launching himself over the Great Wall of China to a certain death then you need to march right down to the drug store and buy some suppositories - they'll do wonders for your outlook.
Thank Youweiwentg
Oct 16, 2002 5:09 PM
my problem, on the other hand, is you. 99% of the time you're a helpful, informative guy. yes, sometimes you're a bit in-your-face, and while I don't always like that, it's not a big deal.
the other 1% of the time you are a complete ass. like that time when you insulted me.
if you choose to see me as a simpleton, that's your opinion. the next time you throw an insult I will simply report your post to Gregg. I've nothing against disagreement, but there are times you are completely uncivilized.
I do not intend to tell people what to think. but if something like this happens again, I intend to do exactly the same thing, except that if you continue to behave like a child I shall ignore you as I should have. should you not be able to stand this, feel free to throw all the insults you wish within the rules of the forum. you can whine about this as censorship if you wish, I do not care. face it, you are telling me what to think as well. I do not care for it any more than you care to hear me show you for what you are.
FWIWweiwentg
Oct 16, 2002 8:13 PM
your first reply to me was perfectly reasonable. as a result, your second one - the one where you called me a pussy - was pretty shocking. what made you change your mind?
personally, I think if you see the need to use such insults to make your point, you need to grow up. I suppose you could say the same about me for bothering to respond to you, but the fact is you threw the first shot.
Oh, Quit It!grzy
Oct 17, 2002 3:05 PM
Make up your mind - are you going to report me to Gregg or are you going to ignore me? You're so non-sensical that it's ludicrous. It's also funny that other peopled weighed in on the pu$$y concept in agreement or didn't you notice? Don't you realize that both of your threats are empty - you might as well tell your mother as well. You've proven that you can't ignore me and Gregg is going to do what - take away my birthday?

Everyone else here seems to have figured out that I view this whole thing as sport - how come you're slower than the rest? I know I really should refrain from beating up on retards like yourself, but it's kinda fun sometimes in a twisted sort of way. All you have to do is stop rising to the bait, but you can't.

Hey, your self imposed stamp of approval on everything right an moral is an insult. Maybe you should apply for Gregg's job?

Simpleton (n) - a silly or stupid person; a fool.
off topic, fine Tom Waits lyric..dotkaye
Oct 16, 2002 8:35 AM
Well the moon is broken
And the sky is cracked
Come on up to the house
The only things that you can see
Is all that you lack
Come on up to the house

All your cryin don't do no good
Come on up to the house
Well come down off the cross
We can use the wood
Come on up to the house

Come on up to the house
Come on up to the house
The world is not my home
I'm just a passin thru
Come on up to the house

There's no light in the tunnel
No irons in the fire
Come on up to the house
And you're singin lead soprano
In the junkman's choir
You gotta come on up to the house

Doesn't life seem nasty, brutish and short
Come on up to the house
The seas are stormy
And you can't find no port
Come on up to the house

[Chorus]

There's nothing in the world
That you can do
You gotta come on up to the house
And you been whipped by the forces
That are inside you
Come on up to the house
Well you're high on top
Of your mountain of woe
Come on up to the house
Well you know you should surrender
But you can't let go
You gotta come on up to the house
Re:Tom Waits lyric.. So Cool. NMSpunout
Oct 17, 2002 4:19 AM
Yupper, Mule Variations. -nmgrzy
Oct 17, 2002 3:06 PM
whatever could you be referring too??? ..... ;o) .... nmJohnG
Oct 14, 2002 6:09 AM
Have some class guys...opencl
Oct 14, 2002 7:15 AM
Just give it a rest. It's over
Yer, right....grzy
Oct 14, 2002 2:03 PM
....at least for him it is! ;-b

Why, I heard he was one in a billion.
.....but they said he didn't need it any more. - nmgrzy
Oct 14, 2002 2:01 PM
A question on the topic posted.Iwannapodiumgirl
Oct 14, 2002 5:30 PM
I assume this relates only to the new carbon/aluminium rims and not the earlier aluminium clincher rims? I have been concerned with my Zipp 303s for a while now.
carbon/alweiwentg
Oct 14, 2002 7:03 PM
the poster was indeed referring to the new clinchers, not the old 30mm full aluminum clinchers.
re: Zipp clincher warping problemsDougSloan
Oct 16, 2002 8:14 PM
I have a pair or 303 carbon clinchers. The front is perfectly fine, but the rear has warped in some weird fashion, that is, the aluminum has flared a bit from at the outside (near the tire) in places, making the brakes very grabby, despite the rim appearing to be true (until you mike it).

Some of your assumptions are way off, though. I don't know any racers that ride the brakes; fact is, I/we plunge down the mountains just like the pros; don't need to be in better shape to go down the hill fast. Plus, if the assumption is that extra heat from braking causes the warping, why would the rear warp and not the front?

I think the aluminum rim portion must be simply too weak to hold the tire pressures. I don't go over 120 psi with these, as there is no need to. So, I know that's not it, either.

I'm sending mine in for warranty. I'll see what they say. Don't forget they could feed someone a line of crap to mask a defect.

Doug
not my assumptionsweiwentg
Oct 17, 2002 5:10 AM
I think I made it clear that these were not my assumptions - they were the assumptions of the Zipp rep that someone else spoke to.
good luck with the warranty department; they say that Zipp has a good one, so you should be covered.
option B is after you get those warrantied, you could get a set of HEDs.