[ire]

For cross season I'm switching from clinchers to tubulars for the first time, so I will have to glue tires for the first time. I've been reading up on the Internet and I'm wondering if anyone has any advice/tips? I found this write up from another site, and he makes the case that gluing tubulars for cross is vastly different from road......how does applying mutliple layers of glue and letting them dry help the bond?

http://crazyfast.blogspot.com/2005_10_01_c...st_archive.html

Sticky Fingers

So, as promised I guess that I will give you the low-down on how I glue my cyclocross tubulars.

I should probably first point out that there is a pretty big difference between road tubulars and 'cross tubulars in terms of how they stay on the rim. A road tubular at 8 bar of pressure will stay on the rim almost by itself, sans-glue. The glue is essentially there to prevent any movement between the tire and rim from starting in the first place. You can try this if you have a new tire and new rim at home; just throw the tire on the rim, pump it up and try to push it off. Hard, yeah? Now release the pressure to 1.8 bar (about 25psi, a standard CX racing pressure) and the tire will slide right off. Scary. That is why standard tub-glueing knowledge does not necessarily apply for 'cross use - the only thing holding the tire on the rim is the glue, there is no help from air pressure.

Next up is the issue of tubular tape. Great for road applications, especially the Tufo variety, horrible for 'cross. Here's why. As has been repeated ad-nauseum in other tubular installation instructions, the bond between tire and rim at the very edge is über-important if you want to keep your rubber on. This is even more critical in 'cross because there is so much water flying around on the course and from the ubiquitous pressure-washers. If there is any gap in this area, water and dirt will penetrate into the bond and weaken it to the point where it may fail in cornering. Tubular tape is bad because it never completely fills the interface between tire and rim. It also causes the center section of the tire to sit a little higher than the edges, making it easier for a gap to form. This is true even of the so-called "Belgian Method", where glue is applied to both tire and rim and tape used to complete the joint. Another bone of contention here- if you are using glue and tubular tape, why not just use glue?

My solution to this problem is Vittoria Mastik´one - and lots of it. Next best is Continental. If you can get your hands on a big can of the stuff, so much the better. If not, be prepared to use about 3 (maybe even 4) litle tubes per wheel, if you are starting with new fresh rims and tires. My team-mate Jiri told me he uses 1 can for 4 wheels. That's a crapload of glue. Some people will say that's too much, but Jiri has also never had a rolled tub in 14 years of high level racing. You decide.

You should probably start by cleaning your rims, just a really quick polish with some light sand paper and then acetone should do the trick. Now you need to apply a relatively thin layer of glue to the rim, making sure that you get it all the way out to the edges of the rim. I don't really care how you spread it, just get it on there. Take your tires, put a little air in them to make them easier to handle and put a thin layer onto the base tape, making sure the entire surface of the tape is saturated (but not dripping) with glue. Now you wait. General rule of thumb is 8 hours of drying time between coats on the rim, but basically as long as it is dry to the touch and not too rubbery you can apply the next coat. Ideally you should do 3 thin-ish coats to the rim this way. For most people who aren't sitting around all day waiting for glue to dry this means three days. Somewhere in these 3 days you need to pull out the tires (remember them?) and put another coat of glue on the base tape. This layer should be über-thick - as thick as you can make it and not have it running off the tape as you apply it. This is when a brush of some type is required. Let that dry overnight too. Finally, on the fourth day you can put the tire to the rim. Put a medium-thick layer of glue on the rim, give the tire a quick stretchy-stretchy and fire it on the rim, starting at the valve. For God's sake make sure you put the tire on in the right direction first, otherwise you will make an atrocious mess peeling it off while the glue is wet (assuming you didn't make an atrocious mess putting it on. Sorry, can't help you there!). Make sure the tire is centered, put it up to 4 bar and leave overnight. Next day, deflate the tire and check the edge bonding by going around the entire circumference of the tire (on both sides), trying to peel it off the rim with your thumbs. If any gaps form, you need to poke some glue in there and inflate the tire again. Leave overnight again. Check the edges again. Now nothing short of a herculean effort should separate the tire from the rim - this a good thing. The glue generally requires 24 hours from the time the tire goes on the rim to reach full strength.

Like anything related to bicycle mechanics, there is a certain amount of feel involved with all this. With tires and/or rims that already have glue on them, less glue will need to be applied. The end result should be somewhere around 0.5mm of glue thickness (even up to 1mm is OK). Sounds like a lot, but it works. With Tufos you can get away with less because there is no seam on the underside.

That's the extent of my knowledge. Argue all you want, but I have never rolled a tub since I started doing it this way.

Please don't sue me
GReain

 

[loco-gringo]

With tires multiple layers helps saturate all of the tape on the tire. On the rim, I'm pretty sure it just fills the voids and gives a more even surface. Two things to know - it's a pain in the ass and Goof Off and acetone are your best friends.

I just started this year. I can't speak for Vittoria Mastik, but Continental glue kicks Tubasti's ass.

 

[ire]

...it's a pain in the ass and Goof Off and acetone are your best friends.

At the risk of sounding like an idiot, are acetone and finger nail polish remover the same thing?

 

[Internal14]

Light sand the rim. Quick cleaning with acetone. Let dry.

Light coat on rim and tire. Leave for 24hrs.

Another thin coat for each the next day. Leave for 6-8hrs.

Another full coat on the tyre, then the rim, wait ten minutes. Stick the two together centering the tyre after it's on.

Inflate to 3bar....then roll the tyre on the ground with your weight on the wheel. This pushed the tyre fully into the rim/glue combo forcing the glue to purge out any air that can be trapped in the glue, tyre seat.

Spin wheel and check for straightness of tyre. Adjust accordingly.

Inflate to 9bar(lower for cross tubs) and leave for 24hrs then go race.

I've glued many tires for top domestic teams, never had a rider of mine roll a tyre. And have successfully mounted cross tubs without incident either.

I'm a fan of being attentive and taking your time and not just slapping a bunch of glue here and there and handing them over. One thing I don't agree with, with the first directions given above, is that a road tubular will stay on by itself. HA! I've seen plenty of tubs roll on the road, and they even had glue. I'm sure he's just trying to make a statement, but still that was a little gross.

 

[ire]

Light sand the rim. Quick cleaning with acetone. Let dry.
...
I'm a fan of being attentive and taking your time and not just slapping a bunch of glue here and there and handing them over.

I'm going to take my time, I'm scared to death of rolling a tire at speed. I'm going to be mounting on Zipp carbon rims, do you still use light sand paper? I thought that was a no no on carbon rims

 

[DirtyMike]

I'm going to take my time, I'm scared to death of rolling a tire at speed. I'm going to be mounting on Zipp carbon rims, do you still use light sand paper? I thought that was a no no on carbon rims

Ok, first off, dont be afraid. instead of sandpaper, I would go with a red scotchbrite. Acetone is different than Nail polish remover. Nail polish remover has acetone, and other stuff, but not all polish remover has acetone.


So, you have cleaned your wheels, you have your new tires. Put air in the tires, you want to strecth them a bit. Start glueing the tire, try not to get it everywhere, let it dry overnight, do the same with the wheels, try not to get it on the braking surface. Next day, put another coat on, both the tire, and the wheel. Let it sit overnight, third night.... guess what, one more coat.


Fourth night, even layer of glue, ten minutesish its time to put your tires on, comfy socks, and use your feet to help hold the tire as you stretch it over the wheel, and let it sit overnight.

 

[-dustin]

the gluing process is easy enough. it's the mounting that is difficult and needs to be practiced. if done improperly, the glue can be forced away from the edge. i prefer the method that Park/ USAC use, which can be seen here:

http://www.parktool.com/repair/readhowto.asp?id=61

what I don't really agree with that i've read in some of the replies is waiting 10 or so minutes to mount the tire. i prefer to do it within a minute, as the glue is still rather wet, which aids in truing the tire. waiting longer, and the glue becomes rather tacky.

Vittoria or Continental glue only. Vittoria gets tacky very, very quickly. I prefer to use a soft-bristled paint brush that has been trimmed. Other i have seen use their fingers. A) i don't want to wear gloves when gluing, B) the brush is a little more delicate. Vittoria and Continental can be mixed if need be.

don't glue a tire expecting a flat. glue it as if you will never remove the tire. i hate hearing "don't glue it so that i can't quickly change a flat."

 

[James]

VeloNews.com had a pretty cool video tutorial a little while back on gluing tubies.
My coworker swears by the tape, he's never had an issue in years and years of use, using tubulars as his daily wheels.
Personally, I hate doing it myself, so I usually farm it out to someone local I trust.

 

[maddog17]

here's the Velonews link for ya

http://velonews.com/article/74487/bike-tech-tubular-tires-a-four-part-video-tutorial

 

[ire]

here's the Velonews link for ya

http://velonews.com/article/74487/bike-tech-tubular-tires-a-four-part-video-tutorial

Velonews sucks.....I click the link to see the videos and it take me to Tour coverage instead of the video I wanted

 

[James]

Velonews sucks.....I click the link to see the videos and it take me to Tour coverage instead of the video I wanted

Must be user error, worked fine for me...

 

[ire]

I glued up my Dugast tires and I rolled the rear during my last race and when I checked the front tonight there were two small spots on one side, and one spot on the other side that had "loosened" (each spot was about an inch long). Each spot was about an inch. I pulled the tire back and inserted lots of glue into each spot and then reinflated. Should this be a cause for concern that the entire tire needs to be reglued?