Technical FAQ: Tape for tubulars, latex tubes, and more
This week, Lennard Zinn addresses questions about attaching tubulars with tape, a cracked bottom bracket shell, and more
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Attaching tubulars with tape
I’m about to embark on a rite of passage as a roadie and begin using tubulars. I’m all for tradition, but I wouldn’t mind a less messy, less toxic, and less arduous approach to attaching tubular to rim. The reviews of the tubular tapes that have been on the market for a while are less than completely confidence-inspiring. But there’s a new product by Effetto Mariposa called Carogna tape. Would you consider putting it through the paces soon and telling us tech-mortals how you think it compares to a high-quality glue job in terms of performance and safety?
The idea of a tape that could chop hours off of attaching tubular tires yet would adhere just as well as a superior gluing job would obviously be a game-changer for tubular users for the reasons you list.
I’ve been using various revisions of Effetto Mariposa Carogna gluing tape for a couple of years now, well before they were released to the market. I have been enthusiastic from the beginning, but the first two versions definitely were not ready for prime time; they did not adhere well enough for my tastes, and they were never sold to the public. This version now available for sale could be just the ticket for those wanting to save some gluing elbow grease, however. I have a number of wheels with the tires held on with Carogna, and those tires are really on there.
A difficult gluing environment is on carbon rims in cyclocross, and I’ve used this new Carogna tape with complete success for that on many wheels. Cyclocross tires, being larger in cross-section, do not mate in shape with the rim bed as well as road tires do. And, being taller, there is higher leverage on the tire when cornering than on a smaller tire. Furthermore, a tire holds onto the rim better the higher the air pressure it has in it, so with the lower pressures used in cyclocross vs. road (25psi vs. 125psi is a big difference), the pressure is not helping the bond much. Finally, the mud and foliage that cyclocross tires ride through, combined with pressure washing them clean, works hard on the edges of the glue job. Earlier versions of Effetto Mariposa tape were susceptible to getting dirt between the tape and the tire, but this current Carogna tape has so far been impressive at keeping dirt out and the tire on.
Carogna is different from most tubular gluing tapes in that its top surface is not only extremely sticky, but it is also very thick. The adhesive Effetto Mariposa used for it was developed for taping undersea communication cables together, so it’s meant for tough environments like wet, dirty roads and muddy ’cross trails. Its thick, sticky surface not only adheres to the tire with a strong grip, but it also flows over time to conform to the underside of the tire. This is important not only when the tire’s radius of curvature is larger than that of the rim, as is the case with a cyclocross tire, but also to conform around the raised ridge formed by the stitching.
You can see me trying to push this Challenge Chicane off of this ENVE XC rim. It had been on there with Carogna for many months, and I’d ridden it a lot in all kinds of slop. I eventually got it off of the rim, but it took a lot of work — similar to a good gluing job. Once the tire comes off the tape, you can then peel the tape off the rim. I find that the best way to do this is to roll it up as in the photo; if you just keep trying to tear it straight up, you can peel the two layers apart from each other and leave a thin layer of tape down on the rim.
Here is a video I did a while ago showing how to glue on a tire with Carogna tape.
Any of you out there who are using Carogna, please keep me apprised of your experience with it.
Latex tubes with carbon clinchers
There seems to be a mix of opinions whether latex tubes are safe to use in carbon clinchers because latex tubes cannot handle heat as well as butyl tubes. Many manufacturers caution against latex tubes, but there are plenty of anecdotes of people running latex tubes without problems — you even seem to say latex tubes are not a problem.
What is the heat tolerance of the average lightweight butyl tube and latex tube? And, how often do carbon clinchers reach temperatures that would lead a latex tube to fail? Is there another reason besides the heat issue that makes latex tubes unsafe for carbon clinchers?
I learned a lot from finding the answers to your questions. I have used latex tubes on carbon clincher wheels without problems, but I would not do it again, after getting the answer below from Challenge (which makes the world’s only seamless latex tubes); I would revise accordingly the answer I gave in the FAQ that you linked to.
Below are responses from the two big brands in latex tubes.
Interestingly, Challenge doesn’t mention this heat issue on its website, and the only mention I found on Vittoria’s site of separate latex tubes (as opposed to latex tubes sewed inside of tubulars) at all was this. Here is some more on the subject of care of latex tubes.
But to answer your last question, other than the heat issue, no, there is no other safety reason not to use them on carbon clinchers. In fact, since latex tubes have so much more puncture resistance (try taking a hammer to latex and butyl inner tubes lying on a table to see for yourself this rather profound difference), they are arguably safer on any kind of wheel where heat buildup isn’t an issue.
It is correct to say that latex tubes should not be used in carbon clincher wheels. It is correct to say that latex does not handle heat well compared to butyl.
Butyl rubber can support much higher temperatures for longer periods of time.
The reason why latex works on carbon clincher wheels (this is my personal opinion), is due to the ability of the rider. Expert riders are able to do descents with limited use of brakes and [thus] give the possibility to the equipment to cool down. Never reach extreme heating. The heat is generated on the external part of the rim and will take time to transfer inside the rim. Generally between tire and rim strip, the tube has no direct contact to the carbon rim and if there is no rim strip it is on the cool part of the rim.
Heat in carbon [rims] does not dissipate fast and generally seems to be concentrated in the braking area.
Criterium and other types of riding do not have [the] problem of wheels heating, so latex can be used with no problem. As manufacturers, we do not know how consumers will use the product, and, to be on the safe side, we prefer to give warning not to use it.
— Alex Brauns
President, Challenge Tech
1. I have run latex with our 3T and Easton carbon clincher wheels with no issue at all, including significant descents in the mountains of Utah. I will, however, forward this to our product manager Christian Lademann for a detailed answer.
— John McKone
Vittoria Road Marketing
2. What is the heat tolerance of the average lightweight butyl tube and latex tube?
If the tube reaches the level of 100-140 degrees Celsius, all kinds of inner tubes will be destroyed.
And, how often do carbon clinchers reach temperatures that would lead a latex tube to fail?
This really depend on several factors, such as rim construction, -size, -resin and -tape. But mainly [it depends] on the end-user brake skills.
Agree that, “shorter, more powerful braking produces less heat buildup than does prolonged braking.” Similar to car brakes.
It’s not the tire bead, but the tube that cannot withstand the heat and give a sudden high pressure to tire bead. By the way, our tires run through a CQ that request 200 percent of the suggested maximum pressure. Example: Open CORSA CX 23mm 10.0 bar max tires have to withstand 20.0 bar at our derailing machine.
Is there another reason besides the heat issue that makes latex tubes unsafe for carbon clinchers?
Tubes are a rather sensitive product in general. Either Latex- or superlight Butyl tubes tend to explode suddenly, if not being used correctly. Some rules need to be followed:
1. Do not overheat the system
2. Do not lock the tube in between tire bead and rim hook
3. Prevent tube over-stretching in general — use recommended air pressure, rim tape and tube size
4. Prevent any sharp edges in the system
5. Prevent contamination with any oily substances
— Christian Lademann
Product Manager, Vittoria S.p.A.
Advice for road tubeless newbies
I have been riding on road tubeless tires and wheels (Ultegra tubeless wheels Fusion 3 tires) for three years now and love them. Last year I rode over 3,000 miles without a flat. Most tubeless road bike riders would like to share this great experience with the clincher community but know there are big pitfalls for the tubeless newbie.
I did not always love my road tubeless tires. After my first puncture that would not seal, I hated my new tubeless tires and almost went back to clinchers. I felt abandoned, helpless, and ripped off. Most bike shops are of little help because most (but not all) of their service staff are unfamiliar with road tubeless and/or do not like the technology.
All road tubeless newbies will need to know how to mount and maintain their tubeless tires. They should also have to know how to fix a leak too large for the sealant but not large enough to trash the tire (these happen to me about once every 1,000 miles). These tasks become quick and easy with the right skills, tools, and tips, but are next to impossible when faced for the first time.
There needs to be a network of road tubeless riders that the tubeless newbie to contact when they need help, because they will all face these frustrating unsolvable (in the newbie’s eyes) problems. Fortunately, I watched the right YouTube videos, read the right blogs, and was able to figure out what needed to be done to make road tubeless riding a pleasure to ride. Not all newbies will be so lucky.
So to all road tubeless newbies … Please find a local road tubeless rider to help you through the learning curve (we are a lonely bunch and would enjoy the company). You will make a new friend and will soon love riding on your road tubeless tires.
Thanks for the tutorial on road tubeless!
Regarding drilling holes in carbon frames
I’d be careful about drilling holes in your bottom bracket. I’ve got a 2007 Trek Madone that has an aluminum shell insert at the bottom bracket. I bought the bike used in 2008 and after a few months I noticed creaking at the bottom bracket. After removing the cranks and bearings I could see the aluminum shell was cracked due to an extra hole drilled next to the cable guide fastener hole. The resulting stress concentration of the close holes, the holes not being de-burred, and the cyclical loading of the cranks caused a crack the connected to the main tube drain holes. Eventually the interface between the shell and carbon frame broke down. Calfee Design repaired the shell and frame, but what a waste. Most likely someone mis-drilled the cable guide and just drilled another hole. As an engineer in aerospace I understand most of the issues, but I’m still scared to drill holes without fully understanding the stresses.
Attached are a few pictures of the crack.