Glueing tubulars [the tubular thread]

Everything about building wheels, glueing tubs, etc.
fdegrove
Tubbie Guru
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by fdegrove

Hi,

Looks like a Vittoria SC to me.

Ciao,
Being a snob is an expensive hobby.

CrazyCaramel
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Joined: Sun Apr 15, 2012 7:37 pm

by CrazyCaramel

Hi guys, recently made the switch to tubs for racing on. After some bad luck with Veloflex Corsa's which were getting expensive to replace I decided to try out Conti Sprinters...

However after gluing them to the rim and pumping them rock solid, next day as the photo shows the tyre appears to be coming away from the base tape!

My question is am I safe to ride it like this or am I asking for a crash :shock:

Image

by Weenie


fdegrove
Tubbie Guru
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Location: Belgium

by fdegrove

Hi,

The entire concept of a tubular tyre is based on the reliability of the adhesion of the base tape.

ciao, ;)
Being a snob is an expensive hobby.

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Calnago
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by Calnago

@crazycaramel: That tire's a mess, but i'm curious... what rim is it glued upon? Does it have a wider than normal (but who knows what normal is these days) rim bed? Even though manufacturers are heavily pushing the wide rim technology these days, which for clinchers makes sense, I don't believe it holds true for tubulars at all. In fact, if you've got a wide rim bed, seems if you try to glue a tubular to it that is not made for the wider rim bed, it will tend to flatten out on the glued portion. This somewhat defeats the whole purpose of a nice tubular ride since it tries to change the shape from round to something else. When you inflate it, the tire wants to inflate in a round shape, but is constricted by the flat spot caused by gluing the tire to a wide rim bed. In these circumstances I could certainly see some stress where you show the separation as the round part wants to pull away from the base tape which is in turn glued to a wide flattish rim bed.

This is purely a theory on my part... but it's intuitive and makes sense to me. Things need to makes sense to me. I'm funny that way.

But in any case... that tire is pretty messed up. I had a Veloflex Roubaix that started separating like that, although not as bad and I think it was due to a lot of water and crud being thrown at it this last winter.

CrazyCaramel
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Joined: Sun Apr 15, 2012 7:37 pm

by CrazyCaramel

Hi Calnago

Its just a Fast Forward F6R wheelset which i don't think are particularly known for having a wide rim bed...

I guess I'll just have to put it down to a manufacturing fault and put another tub on :(

Thanks for the replies :thumbup:

Geoff
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Location: Canada

by Geoff

Frank is definitely correct, but just because the edges of the basetape are peeling, it does not necessarily mean that the entire basetape is compromised.

I have had that happen lots of times without ill effects. While more common on small-batch tires than the large factory offerings, it definitely happens (I have just had it happen on a pre-production 4000GP). You just need to check the tire well. If the glue job has cured for awhile, deflate the tire and check the adhesion of the basetape and tire casing all the way around on both sides. If the basetape still looks good, I would bet you will be fine.

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Calnago
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by Calnago

Yes, I said the tire's a mess. But not necessarily dangerous unless the bond is so weak between between the tire and base tape that you're worried about it just completely separating. Can't tell that from pics but as long as you feel it's still got a good bond except for a "bit" of separation on the edges it should be ok to ride. Just keep an eye on it. My Roubaix did that (not quite as bad and only after riding in some pretty cruddy conditions over time), but if a brand new tire did that on the initial mounting I'd be looking for a warranty replacement. Doesn't sound like it was a tire:rim mismatch like I was wondering about.

petepeterson
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by petepeterson

I had a flat on a veloflex carbon this weekend. Tire has aprox. 300km on it. I love tubulars and I love veloflex but this is the second rear flat in a row I`ve had on them after little milage. I get really frustrated when it costs me $100 after only a few rides. I have never sent tubulars away to tirealert for a new tube before. Curious to hear if any of you do this....

sungod
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Location: it's raining, it must be uk

by sungod

repair them, it may sound fiddly, but it's straightforward, i've only done three, the tubular repair thread has all the info, just be methodical and you can do it, or you can send them away

btw if it's just a small puncture, sealant will probably fix it, i use tufo extreme, worked well

imho you need to build up a collection of a few tubs, then you can save up ones needing repair and do them in batches (or send them away for repair if you prefer)

fdegrove
Tubbie Guru
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by fdegrove

Hi,

petepeterson wrote:I had a flat on a veloflex carbon this weekend. Tire has aprox. 300km on it. I love tubulars and I love veloflex but this is the second rear flat in a row I`ve had on them after little milage. I get really frustrated when it costs me $100 after only a few rides. I have never sent tubulars away to tirealert for a new tube before. Curious to hear if any of you do this....


When it comes to tyres the likes of Veloflex, FMB etc., the best advice I can give is to age them for at least six months in a dry, dark place.
After that puncture resistance increases tremendously with no noticeable penalty on rolling resistance. This is true for most tyres but in particular for any hand glued ones.

As people like Geoff, many others including myself have testified, it makes a world of difference. I do the most unbelievable tracks with Veloflex tyres and for many years in a row do seem to avoid flats.
I do confess that I avoid urban areas like the plague but still, a well aged tub a la Veloflex (and consorts) is about the most puncture resistant I know of. Besides being an absolute joy to ride.

Early punctures can be utterly frustrating, can be chalked down to bad luck just the same but more often than not are just a case of a rider in a hurry to put his new shoes on the road so to speak.

People like Tirealert do the wise thing, they pull out the inner tube and replace it with a new one. From what I heard they do a fine job.

Ciao, ;)
Last edited by fdegrove on Wed Aug 21, 2013 1:13 am, edited 1 time in total.
Being a snob is an expensive hobby.

petepeterson
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Location: 604

by petepeterson

Thanks all - FWIW the tires were aged 4 months in my bike room (cool & dark) from me receiving shipment which adds to the frustration.

As suggested I will save up a few flats and send a way a batch. It is $20 a tire at Tirealtert.

For now I am going back to try Corsa EVO`s and will age some carbons over the winter.

TuplaO
Posts: 79
Joined: Fri Apr 08, 2011 7:00 pm

by TuplaO

You say you aged them for four months after getting them. What was the date stamped on the basetape?

Geoff
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Location: Canada

by Geoff

That sucks, for sure, but don't let it discourage you.

I will admit, the locale in which you ride and your style of riding has a lot to do with punctures (we happen to be 'lucky' to live where a glass bottle recycling programme is sponsored by the Provincial Crown, so a big part of the problem gets eliminated), but tubulars tend, in my experience, to be less prone to punctures than clinchers due to their comparative resistance to pinch-flats.

On the subject of aging tires, I have found that it is not so much dependent on any set time, but on the condition of the tire. When a 'hand-made' tire is 'ready', you will be able to see it clearly. The 'white' of the sidewall will appear yellowed or even amber in colour and the tread itself will form a 'patina' that will appear slightly brown, or even rust-coloured. The combination of the complete curing of the glues used in the construction of the tire and the hardening of the tread rubber itself seems to help the puncture-resistance of the tire.

I don't think that the tire is necessarily 'strengthened', but stuff that can puncture a tire seem not to 'stick' onto the surface of the tread as well. As a result, it appears that foreign matter will fall-off from centrifugal force or becomes more easily dislodged by your fingers as you brush the surface of the tire. Anyway, it seems to work for me.

I have to glue-up some tires soon (lent a set of race wheels to a friend who punctured them - clincher riders) and the FMB tires I will be using have been aging for around 3 years.

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rainerhq
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by rainerhq

Do you suggest to age real tubs always 6 months, no matter the date on stamp?
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by Weenie


sungod
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Location: it's raining, it must be uk

by sungod

if the rubber is like veloflex/similar, they do seem to get tougher over time, 2011 vs. 2013 carbons you can feel the difference by touch (i happen to have some nearby, i just checked)

but conti/similar where the rubber is vulcanized, it doesn't make a difference

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