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Was wondering what everybody thought of the Pro three spoke carbon wheel coming apart during Tirreno-Adriatico Time Trial. Does anybody think the tubular tire came off causing the wheel to break apart when it touched the street? Or this is what Shimano will blame it on. Kinda concerning and Gianni very lucky he was not seriously hurt! What's your thought.
 

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When it happened, the commentators I was listening to thought it was a tire failure.

They said he flatted/blew out or the glue job failed or both and the tire came completely off of the rim. Once the rim hit the pavement with no tire on it, it broke.

After the stage one of the commentators was talking to G when G told him that two more bikes had the front tires come off of the rim, causing them to hit the ground and break. So three tire failures, three broken rims, one catastrophic. All on the front wheels.

Him and three others had to just freewheel for about a whole kilometer while waiting for at least one of the three to get a new bike and get back on the group. Have to finish with 5 and they only had 4 riders that didn't have tire/rim trouble.

At this point I'm inclined to believe him, it was Dan Lloyd by the way doing the commentating, he's pretty stand up it seems. But of course it's just a guess and observation.

First thought might be failing carbon, but looking at the video, listening to the riders and the commentators, I'm with them on it being a tire problem.
 

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They said he flatted/blew out or the glue job failed or both and the tire came completely off of the rim. Once the rim hit the pavement with no tire on it, it broke.
Sounds like a quality problem, as I've had a blow out on my Zipp 202s and the rim hit some pavement and the rim didn't explode.
 

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I'll bet some Team Sky mechanic failed to properly glue the front tubs on the TT bikes. The tire on Moscon's bike can be seen coming off the rim and flopping around just before the rim disintegrates. I'll bet similar things happened to the other wheels.

I don't think you can blame the Moscon crash on JRA wheel failure. I do think that such a catastrophic failure when the rim hits the ground is a bit ridiculous, regardless of the speed we're talking about here. Luckily, the chance of me buying a carbon tubular tri-spoke wheel are zero so I'm not fussed.
 

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Pro says tire caused Sky's catastrophic wheel failure at Tirreno | VeloNews.com


The rims mandate a minimum of 25mm width tires.

Sky was using 22mm or 19mm tires. The rim is 24mm wide. Therefore the rim was constantly impacting the ground and eventually shattered.

They claim, basically, nothing at all was wrong with the rim. If they use those tires again, the rims will shatter and break again. They had 3 break that day.

So... read the manual, follow the manual, stop fuking it up in the name of marginal gains.
 

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Pro says tire caused Sky's catastrophic wheel failure at Tirreno | VeloNews.com


The rims mandate a minimum of 25mm width tires.

Sky was using 22mm or 19mm tires. The rim is 24mm wide. Therefore the rim was constantly impacting the ground and eventually shattered.

They claim, basically, nothing at all was wrong with the rim. If they use those tires again, the rims will shatter and break again. They had 3 break that day.

So... read the manual, follow the manual, stop fuking it up in the name of marginal gains.
If a wheel can't be made to use a 23mm tire, it's not worth making, using or buying. One company's 25 can measure smaller than another company's 23. So you could run the wheel with a properly spec'd tire and still have the problem.

Shimano is speaking out their butts trying to pass the blame. Makes them look bad. There are other wide rims out there that can safely take smaller tires than 25mm. Shimano didn't do it right of their wheels can't take a 23. Even if the rim is wide, with the narrow tire, the rim isn't going to hit the ground with air in the tire, and it seems the wheel actually failed before the tire came off. Granted, if the tire deflates, it may cause a problem, but that's true of any rim, really. Obviously, if the tire comes off, any wheel will likely take damage.

If that is shimano's explanation, I won't be buying or recommending those wheels.

Sent from my SAMSUNG-SM-J327A using Tapatalk
 

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Keep in mind that we're talking tubulars here, not clinchers.

So a 19mm tubular is actually 19mm at it's widest point, there is no bead for it to snap into, it just sits there on the surface of the rim, well glued. So in this case there's bare rim sticking out on both sides of the tire.
 

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Keep in mind that we're talking tubulars here, not clinchers.

So a 19mm tubular is actually 19mm at it's widest point, there is no bead for it to snap into, it just sits there on the surface of the rim, well glued. So in this case there's bare rim sticking out on both sides of the tire.
What makes me wonder, is even with rim exposed on either side of the tire....it would take all but pinch-flatting a tubular to ding the rim against the ground. Which given that we're dealing with racers that are fly-weight, and tubulars that are pumped close to their max pressure, riding on great (aside from a manhole cover) roads...seems at a glance unlikely.
 

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Shimano is speaking out their butts trying to pass the blame. Makes them look bad. There are other wide rims out there that can safely take smaller tires than 25mm. Shimano didn't do it right of their wheels can't take a 23. Even if the rim is wide, with the narrow tire, the rim isn't going to hit the ground with air in the tire, and it seems the wheel actually failed before the tire came off. Granted, if the tire deflates, it may cause a problem, but that's true of any rim, really. Obviously, if the tire comes off, any wheel will likely take damage.
I wouldn't expect a legit wheel would explode like that with NO TIRES at all nevermind when using the most common size in the target market they are pushed at.

And yes any rim will be damaged with no tire pressure but here we're talking something I'd say is a bit more than "damage".
We've all seen guys nail train tracks or whatever at 35 while weighting the bike and f up rims pretty bad. But exploding like that is a whole other thing.
 

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I wouldn't expect a legit wheel would explode like that with NO TIRES at all nevermind when using the most common size in the target market they are pushed at.

And yes any rim will be damaged with no tire pressure but here we're talking something I'd say is a bit more than "damage".
We've all seen guys nail train tracks or whatever at 35 while weighting the bike and f up rims pretty bad. But exploding like that is a whole other thing.
yep, pretty much what I think. Either a design flaw if what shimano says is true, or poor construction or both. But to say it's because the tire was a mm or 2 narrow is nonsense.
 
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