Glueing tubulars [the tubular thread]

Everything about building wheels, glueing tubs, etc.
sungod
Posts: 1701
Joined: Fri Dec 24, 2010 9:37 pm

by sungod

that's should be a good width on lw

i've found there's a huge difference in handling between veloflex sprinter (22mm) and criterium (23mm) on the front wheel, just that tiny difference completely changes how the wheel behaves in stronger wind (35km/hr upwards) and changing yaw angle

must admit i've incorrectly posted on ww that lw wheels 'catch' in the wind, but they only do it if the tyre is too wide, that 22-23 transition is where it all goes wrong

skinny tyres ftw

joe1234
Posts: 68
Joined: Mon Aug 28, 2017 5:29 pm

by joe1234

sungod wrote:
Wed Oct 03, 2018 7:50 pm
that's should be a good width on lw

i've found there's a huge difference in handling between veloflex sprinter (22mm) and criterium (23mm) on the front wheel, just that tiny difference completely changes how the wheel behaves in stronger wind (35km/hr upwards) and changing yaw angle

must admit i've incorrectly posted on ww that lw wheels 'catch' in the wind, but they only do it if the tyre is too wide, that 22-23 transition is where it all goes wrong

skinny tyres ftw
:beerchug:

by Weenie


gramsqueen
Posts: 69
Joined: Wed Jun 27, 2018 5:15 am

by gramsqueen

Calnago wrote:
Wed Oct 03, 2018 2:46 pm
Completely flat? Definitely would need to add air but I wouldn’t think they’d be completely flat. Yes, I’d be checking the extension joint (I use Teflon plumbers tape and tighten before install) and also check the valve core just to be sure it’s snug and not leaking.
It's already installed now with an extension with removable valve core. Can I just use the valve core ledge to tighten the whole extender onto the valve stem?

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dj97223
Posts: 677
Joined: Sun Nov 06, 2005 7:27 pm

by dj97223

Yes. That has worked for me. One of these tools, like Campagnolo sells in a harder plastic, should do the trick without rounding out.
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Calnago
Posts: 6922
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

gramsqueen wrote:
Calnago wrote:
Wed Oct 03, 2018 2:46 pm
Completely flat? Definitely would need to add air but I wouldn’t think they’d be completely flat. Yes, I’d be checking the extension joint (I use Teflon plumbers tape and tighten before install) and also check the valve core just to be sure it’s snug and not leaking.
It's already installed now with an extension with removable valve core. Can I just use the valve core ledge to tighten the whole extender onto the valve stem?
The trouble with tightening the extension by using the valve core ledge is that the valve core itself will become very tight, making removal (without unscrewing the extension along with it) difficult. And you will want to be able to remove just the core in the event of a puncture where you want to add sealant. If you can get a grip on the extension itself with some pliers that may be a better way to go but you have to be cognizant of just how much you’re actually twisting the tube inside the tubular. Best way obviously is to get the extension on tight and leakproof before mounting the tubular, as doing that once it’s glued with no more access to both sides makes it more difficult. But you should still be ok as long as you’re a little more diligent in ensuring that things are tight enough for now, and chalk it up to experience for next time.
Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

snaxez
Posts: 13
Joined: Fri Jun 06, 2014 7:14 pm
Location: Estonia

by snaxez

I got some new DT Swiss RC38T DB wheels for my disc build, and I can deside if I should glue on 25 or 28mm Corsa-s on them. The wheels are only 21mm.
On my old rim brake tubulars I hade 25mm corsa on 23mm rim, and that was ok. Would 28mm corsa be too much for only 21mm wide rim?

sungod
Posts: 1701
Joined: Fri Dec 24, 2010 9:37 pm

by sungod

using such a wide tyre will be poor aerodynamically, you'll have a lightbulb' profile, on fast corners i'd also expect the tyre to squirm

unless you are going wide to ride on poor surfaces i can't see any benefit to putting wide tyres on these rims

on those rims, for road i'd fit veloflex sprinter on the front and criterium on the rear

snaxez
Posts: 13
Joined: Fri Jun 06, 2014 7:14 pm
Location: Estonia

by snaxez

Roads here are not the best, so would not like to go under 25mm. Would there be a need for wider tires with disc brakes compared to rim brakes, or is there no difference?

gotgame
Posts: 83
Joined: Sun Dec 29, 2013 3:44 pm
Location: heaven, EU

by gotgame

will post it here, maybe someone needs a new set of tubulars :)


if anyone interested in a set of mavic cosmic pro carbon sl t (tubular) brand new at good price, PM me.

wheels are brand new, retail accesories incl mavic 25c tubes (850€ for Europe, 1000$ worldwide, paypal and shipping incl.) can do also ebay sale
Colnago e1 gazzetta dello sport - sz52s / Pinarello gan RS ulterga di2 - sz52 / Caadx 2019 vulcano green sz54

Jannekallio
Posts: 4
Joined: Tue Jan 15, 2019 2:44 am

by Jannekallio

While ago one expert who had been working with rolling resistance tests, said that in order to have best possible CRR you should use very little glue..

Any other opinions?

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Calnago
Posts: 6922
Joined: Sun Nov 07, 2010 9:14 pm

by Calnago

Well, I use Vittoria Mastik One and I find that one thin layer on the rim, and one thin layer on the base tape... then set aside overnight to cure... Next day: one more thin layer on the rim to make it easier to mount and straighten provides a super strong bond. It's contact cement... activated by pressure. It's why you can carry around a preglued tire all folded up and it doesn't become stuck together so bad that you can't unfold it to mount. But when you try to remove it after it's been inflated and ridden on, it's surprising just how strong a bond has been created. It just needs a layer to bond to on each surface. Any more layers than that is just building up an unnecessary bed of thickness inbetween the tire and rim, and in the event it does get super overheated... too much glue when softened could create a squishy pool of soft glue for the tire to rub around on. That's not what I want. As it is, it still takes me a good 15 minutes to remove a tire glued that way, short of ripping it off and risking pulling some carbon fiber away in the process... not a good removal method to use on carbon rims. Just follow the instructions that Vittoria outlines for it's Mastik One and you'll be fine, better than fine. I've experimented with more layers, and the bond is no better, and arguably worse if things get really hot for the reason I just described. As for rolling resistance... well, you be the judge, I'm sure less is more in that regard but really...
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Colnago C64 - The Naked Build; Colnago C60 - PR99; Trek Koppenberg - Where Emonda and Domane Meet;
Unlinked Builds (searchable): Colnago C59 - 5 Years Later; Trek Emonda SL Campagnolo SR; Special Colnago EPQ

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